0501256 790 m
MSS SP-92-1999
MSS Valve User Guide
Standard Practice
Developed and Approvedb! ? urers Standardization Societyof the
Valve and Fittings Industry, Inc.
127 Park Street, N.E.
Vienna, Virginia22180
(703) 281-661 3
COPYRIGHT Manufacturers Standardization Society of the Valve and Fittings
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MSS STANDARD PRACTICE SP-92
An MSS Standard Practice is intended as ? practiceby the manufacturer,the user, andthe general
public. The existence of an MSS Standard Practice does not in itself preclude the manufacture, sale, or use of
products not conforming to the Standard Practice. Mandatory conformance is established only by reference in a
code, specification, sales contract, or public law, as applicable.
Unless otherwise specifically noted in this MSS SP, any standard referred to hereinis identified by the date of issue
that was applicable to the referenced standard(s) at the dateof issue of this MSS SP. (See Annex A).
In this Standard Practice all notes, annexes, tables, and figures are construedto be essential to the understandingof
the message of the standard, and are considered part of the text unless noted as “supplemental”. All appendices
appearing in this document are construed as “supplemental”. “Supplemental”information does not include manda-
tory requirements.
I U.S. customary units in this SP are the standard; the metric units are for reference only.
This document has been substantially revised from the previous 1987 edition. It is suggested that if the user is
interested in knowing what changes have been made, that direct page by page comparison should be made of this
document.
Non-toleranced Dimensions in this Standard Practice are nominal, and, uselessotherwise specified, shall be consid-
ered “for reference only”.
Any part of this standard may be quoted. Credit fines should read “Extractedfrom MSS SP-92, with permission of
the publishel; the Manufacturers Standardization Society.” Reproduction prohibited under copyright convention
unless written permission is granted bythe Manufacturers Standardization Society of the Valve and Fittings Industry,
Inc.
Originally Approved February1980
Copyright O, 1980 by
Manufacturers Standardization Societyof the
Valve and Fittings Industry, Inc.
Printed in U.S.A.COPYRIGHT Manufacturers Standardization Society of the Valve and Fittings
Licensed by Information Handling Services
MSS STANDARD PRACTICE SP-92
FOREWORD
When ? is usedfor ? cations and in various operating environments, it is reasonable
to expect that the performance of such ? flect uponit suitability for the specific service as well as its
proper installation and maintenance. Recognizing that operating problems involving industrial valves frequently
involve the use of valves not properly selectedfor the intended service, or adversely affected by improper handling,
installation, operation, or maintenance, the manufacturers Standardization Society has prepared this Valve User
Guide.
The Societyor its members, jointly or severally, makeno guarantee and assume no liability or responsibility regard-
ing the contents of this document. It has not been possibleto include everyconsideration related to the satisfactory
use of valves, and. especially in abnormal or unusual circumstances,the possible -need for other considerations and
precautions should be recognized.
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M SS STANDARD MSS PRACTICE 5p-92
TABLE OF CONTENTS
SECTION PAGE
TERMS AND CONDITIONS ..................... i
..
FOREWORD _....~ ........................... II
...
TABLE OF CONTENTS ....................... III
1. SCOPE ....................... 1
2. REFERENCES ..................... 1
3. SELECTION ..................... 1
4. SHIPPING AND STORAGE .................. 5
5. INSTALLATION ...................... 6
6. OPERATION AND MAINTENANCE ................ 9
ANNEX A: Referenced Sources and Applicable Dates ............... 16
.. .
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MSS PRACTICE STANDARD SP-92
VALVE USER GUIDE
1. ScOpE cycle) cost criteria should be used only in
choosing between alternativesthat are known
This Guide presents information which shouldbe to satisfy the service requirement.
helpful to users desiring to avoid the most obvi-
ous causes of problems with valves. The material 3.2 Pressure-Temperature Rating
is divided into four sections, “Selection”, “Ship-
ping and Storage”, “Installation”, and “Operation 3.2.1 The pressure-temperature rating of the
and Maintenance” valve must be properly selected for the ser-
vice requirement.If the service involvesa tem-
perature above 100 “F (38OC), the valve pres-
2. ,REFERENCES sure ratingat the service temperature must be
verified as meeting the requirements theof ap-
The standardsand specifications listedin An- plication.
nex ? are included as useful
source documents to help userthe understand 3.2.2 If system testing will subject the valve
the various valve types and their operational to ? ess of its working pressure
limitations. This is particularly important when rating, then the intended testing pressure and
a statement explaining whether the test pres-
selecting equipment for ? re/
sure is through the opened valveor ? mperature/fluid application. tial across the closed valve, should be included
in the purchase specification.
3. SELECT108
3.3 Bending. Strenvth
3.1 General
3.3.1 Piping systems are subject to mechani-
3.1.1 It is beyond the scope of this standard
cal constraints at fixed support points such as
practice to make recommendations for specific rigid nozzles, anchors, etc. Cold springing at
applications because misapplicationof ? system temperature changes, to-
type could result in operating problems which sether with gravity, possible inertia loads,
adversely affect system safety and effkiency. landslides, non-uniform subsidence in buried
However, observance of the considerations, lines, etc. all potentially affect the bending
recommendations and cautions offered herein moment at various points inthe piping.
will provide increased assurance of satisfac-
tory valve performance. 3.3.2 Valves are also subjectedto the bending
moment occurring in the adjacent pipe which
3.1.2 The valve industry offers ? in addition to the normal pressureloadings.
of valve types and materials for use in indus-
Bending loads cancause deformation in valve
trial piping applications. There are usually bodies that can be detrimental to valve func-
several possible choices for ? br>tional performance. It is therefore ? any one valve may offer significant ad- mended design practice to avoid locating
vantages andor limitations compared to an- valves at pointsof large bending loads.
other valve. It is good practice to consult the
manufacturer regarding specific requirements.
3.3.3 In many cases, normalvalve design prac-
The purchasing function includes the respon- tice resultsin ? reater than the
sibility for securing the required valvesat the
strength of the adjoining pipethereby provid-
lowest cost, but mustalso ensure thatthe valves ing inherent protectionagainst valve damage.
purchased are in fact satisfactory for the in-
In other cases, piping conditions or systems
tended service. The lowest total user (life
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MSS STANDARD PRACTICE SP-92
designs may actuallyincrease the possibility of tion “Fire Testing” is covered by such stan
harmful valve body deformation. dards as API 589, “Fire Test for Evaluation o.
Valve Stem Packing” and API 607, “Fire Test
The following are examples of possible prob- for Soft-Seated Quarter-Turn Valves”.
lems.
3.5 Pressure SurFe
a) Basic “standard” valves that are made into
“venturi” type valves by providing enlargedend 3.5.1 Closure of ? d
connections on the smaller standard basic line causes the velocity of the fluid to be re-
valves. duced to zero. If the fluid is ? br>compressible liquid, the inertia of ? Cast ^iron valves installed in steel piping. column produces ? at the valve
whose magnitude is inversely proportional to
c) Any “standard” valve installed in heavy wall the time required for closure. The surge pres-
“overweight” piping where the extra thickness sure is also proportional to the length of the
may cause the pipe to be stiffer and stronger upstream fluid column and the fluid velocity
than the valve. prior to closure initiation. If the application
involves ? ine, ? .3.4 Valve designs having ? stream line,high velocity, and/or rapid closure,
ing strength should be used if there is reason singly or in any combination, the possibility
for concern regarding possible high’ bending of an unacceptable pressure surge should be
loads. investigated.
3.4 Fire Safetv 3.5.2 Also to be considered are condensation
induced pressure surges which occur when a
3.4.1 The terms “Fire Safe” or “Fire Tested” fluid velocity change is caused by rapid con-
are not definitive and should not be used with- densation or when ? acceler-
out an accompanying specification of what is ated bycontact with steam. An example would
required. Such ? ay be provided be when condensate collects on one side of a
in the form of ? ? osed valve that has steam on the other side,
or for limitations on the valve failure mode. then opening the valve will cause collapsing
Examples of such limitations are: steam voids,sharp pressure surges and accel-
eration of condensate slugs. Condensation
a) Destruction of elastomeric or polymeric ma- induced pressure waves can result in pressure
terials in the valve shall not result in gross pulses that are significantly higher than those
valve pressure boundary leakage. produced by ? osure. In such
events, non-shock rated gray iron valves in-
b) Destruction of elastomeric or polymeric stalled in steel piping systems are particularly
materials in the valveshall not result in leakage vulnerable to catastrophic failure. Traps are
greater than ? when the valve is required to prevent condensate accumulation
closed. and “blow off’ valves located atthe low point
in the system are needed to ensure condensate
c) External heating of the valve shallnot cause drainage. Operation and maintenance person-
uncontrolled buildup of pressure in the body nel must be aware of the function of these de-
cavity of ? alve. vices in relationship to the “shut-off valve
operation and the necessity for their being in
3.4.2 Requirements related to after-fire oper- proper working order.
ability and seat tightness are difficult to define
other than by actual testing using standardized 3.5.3 The flowing media should be consid-
procedures. Valve post-fire operabilitysimula- ered as being “stopped” instantaneously in the
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STDmMSS SP-92-ENGL L999 ? T94 I
MSS STANDARD PRACTICE SP-92
case of ? sure on ? am lines, or in liquid lines with low or un-
sal. Consequently, the pressure surge maybe steady flow, should be described fully in the
very high depending on the velocity of there- purchase specificationso that the manufacturer
verse flow at the instant of closure and the can evaluate the suitability of the valve design
length of the fluid column. Applications of as some check valves requirea minimum flow
check valves in liquid lines shouldalways be rate for stable operation.
evaluated for possible pressure surge (water
hammer) problems. 3.6.6 Check valves should not be located close
to upstream flow disturbances such as control
3.6 Check Valve Apdication valves, elbows and tees. Turbulence in the
flowing fluid entering the valve may cause disc
3.6.1 Check valves are actuated by the flow motion and excessive wear.is Itrecommended
or pressure of the line fluid. Problems involv- that check valvesbe located at leastfive pipe
ing excessive wear of internal parts or noisy diameters downstream from elbows ahd ten
operation can result from the ‘use of check diameters downstream from tees and control
valves which are not fully openedby the nor- valves; evengreater distance is recommended
mally sustained flow. in the case of control valves that operate with
high pressure drop or severe cavitation.
3.6.2 ? uld not be used as a
primary “shut-off’ valve for any application, 3.6.7 Check valvesare normally seated by *
including energy source isolation. Check forces due to reversed pressure and may not
valves should be applied as containment de- seal “through leakage”as tightly as some other
vices to preventgross backflow. Forexample, valve types.Also, some check valves may not
to restrict backflow into equipment such as seat and seal tightly with very low reversed
boilers and pumps operating off ? s. Use of ? instead
header. of ? lve should be considered
if sealing tightness is essential. The use of
3.6.3 Piston and ball check valves that are another type of valve (shut-off valve)in series
designed withclose diametrical clearancesbe- with the check valve may be considered.
tween the moving parts are sensitive to a
“sticking operation” when used in ? ottling Service
where internal rust or other solids may de-
velop. It is recommended that check valves 3.7.1 Valves used to control the rate of fluid
selected for use inthis type servicebe tolerant flow may be subject to severe fluid turbulence
of ? the valve. which can have the effect of creating ? conversion within the valve and pip-
3.6.4 Applications involving gas steam or flow ing system. This energy conversionis usually
may be complicated by an energy transfer indicated by high noise levels,either by cavi-
phenomenon which can cause valve cycling tation of liquids or by shock waves from gases.
even under steady flow conditions. Such cy- (The noise in ? an example of a
cling may cause rapid wear and premature low level cavitation noise.)
valve failure or malfunction.Valve closure el-
ement cycling may also be ? 7.2 The possibility exists for mechanical
the flow is cycling as it would be at the dis- damage to the valve and piping system when
charge of ? ump. throttling of liquid flow results in severe and
continuous cavitation conditions. Likewise,
3.6.5 The preferred sizing of ? with gas flow under severe throttling condi-
such that at normal sustained flow, the valve tions, shock wavescan possibly result in dam-
closure element will be held againstits stop in age to the system.
the full open position. Applications in gas or 3.7.3 The valve manufacturer should be
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STD-MSS SP-92-ENGL 1999 ? 920 m
MSS STANDARD PRACTICE SP-92
consulted on proper valve selection for throt- pansion or vaporization of the liquid. Con-
tling applications. versely, cooling an undrained cavitybelow the
freezing point may also result in volumetric
3.8 TemDerature Changes expansion of the media. These expansions can
result in extremely high pressures occurring
3.8.1 Valve structural materials expand with in the valve.
rising temperatures and contract with falling
temperatures. Generally, increasing tempera- 3.9.2 In addition to the risk of pressure bound-
ture causes ? hanical strength ary leakage or failure, high center cavity pres-
which is regained on return to ? in some double seated valves may cause
perature. ? n-uniform tempera- very high opening force requirements (pres-
ture in astructure may impose significant ther- sure locking). This should be considered if
mal stresses or distortion with possibleadverse reliability of valve opening is essential.
effect on valve performance.
3.9.3 The purchaser should consider the ne-
3.8.2 The possibility of thermal stress fatigue cessity of providing positive means for pre-
should be considered in applications involv- vention of such overpressurization where these
ing frequent temperature cycling. This possi- conditions can be anticipated.
bility is increased by any one or ? of the following: increasing temperature 3.10 Material Compatibility
range, increasing temperature level, increas-
ing rate oftemperature change, increasing ther- 3.10.1 It is important that valve structural
mal conductivity of the fluid, increasing thick- materials and lubricants be chemically com-
ness of metal sections or increasing the num- patible with the other piping system compo-
ber of cycles. In some cases, thermal cycling nents, line fluids and the environment. Guid-
may also increase the tendency for stem seal ance should be obtained from informed
leakage. sources such as the valve manufacturersor the
system engineers whenever there appears to
3.8.3 Practical problems can result from fail- be reason for such concern.
ure to anticipate temperature effects. An im-
portant example is ? valve in 3.1 ? t
steam service that is normally open to flow-
ing steam and then closed in the hot condi- 3.1 l.1 Manually operated valves are usually de-
tion. The body-bonnet will contract more in signed to require ? nt of physical
cooling down from the initial hot condition effort applied to ? andle to open
than the stem fromits initial “partly cool” con- or closeat rated working pressure. However, typi-
dition. The result is ? ning of cal use of ? ve ? r>the body-bonnet height and/or the relative pressure therebysubstantially reducing the differ-
lengthening of the stem-wedge height with ? across ? ement and
resulting “jamming” of the wedge into the ? ed operating effort. Lower oper-
seats. The valve may then be found to be ating effort can also be achieved by opening ? in the closed position when anattempt pass valve in some cases.
is made to open the valve.
3.11.2 In all cases, the purchaser should deter-
3.9 TrapDed Pressure mine that the manually operated valves selected
will be capable of beingoperated under the antici-
3.9.1 When ? eated valvecon- pated operating conditions by the personnel re-
taining liquid is heated (e.g., from process con- quired to perform such operation. Oversize
dition, radiation or solar heating) the cavity handwheels and gear operators will require spe-
pressure will increase due to volumetric ex- cific operator training to prevent applying damag-
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ing overloads.Refer to paragraph 6.1 1. The valve usually opento minimize exposureof the func-
manufacturer should be consulted for specific in- tional surfaces. Butterfly valves are usually
struction on operating torques. shipped closed or in ? osition.
Check valves can be shipped in either the
“blocked open” or the “blacked closed” posi-
4. SHIPPING AND STORAGE tion.
4.1 Introduction 4.3 Handling
4. l. ? es; as manufactured, 4.3.1 Appropriate care in handling valves
tested, and ready for delivery users, to are typi- should be complementary to the degree of pro-
cally well designed products that are properly tection provided in preparation for transport.
fabricated and inspected and capable of giv- ? tion in handling valves
ing satisfactory service. Valves enjoya degree should be to avoid damaging the protection
of inherent protection against degradation by provided for shipment. An obvious general rule
either impact, impigementor invasion of harm- is that valves should never to thrown or
ful materials after installation. However, the dropped. Valves whosesize requires handling
intervening period betweenthe production test by crane or lift truck should be “slung” or
and the installation in line may involve sub- “rigged” carefully to avoid damageto exposed
stantial exposure to such degration which can valve parts. Handwheelsand stems, in particu-
adversely affect the subsequent service per- lar, should not be used as lifting or rigging
formance of the valves. points for large valves.
4.1.2 Observance of the recommendations and 4.4 Storage
cautions offered herein should provide in-
creased assurance of satisfactory valve perfor- 4.4.1 The problems to be considered in re-
mance. gard tostorage are generally the same as those
previously discussed relative to preparation for
4.2 PreDaration for Transuort transport. The time element is important as
conditions that would not be seriously harm-
4.2.1 Consideration should be givento the ful for ? ld result in
need for protection against mechanical dam- need for costly re-conditioning if extended
age and harmful exposure to dirt or other del- over weeks or months.
eterious material. In most cases, the critical
points of exposure are the valve end ports and 4.4.2 Certain valve components may have a
exposed surfaces of the stem. The following recommended shelf life which shouldbe stated
checklist may be helpful in avoiding or mini- by the manufacturer and the purchaser should
mizing problems: take appropriate action.
a) Is the valve dry or internally protected 4.4.3 Valve end protectors should not be re-
against rusting or galvanic corrosion? moved unless necessary for inspection and in-
stallation.
b) Are the valve ends protected against me-
chanical damage to either the threads, flange 4.4.4 Protection against weather should be
faces, weld end preps,etc.? provided. Ideally, valves should be kept in-
doors with actual valve temperatures always
c) Is the valve in the best set position for han- higher than the dew point.
dling? Globe, diaphragm, and gate type valves
are usually shipped closed to prevent rattling. 4.4.5 Valves should be supported off the
Ball, plug and through conduit type valvesare ground and/or pavement and protected by a
watertight cover if outdoor storage is unavoid-
able.
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STD-MSS SP-72-ENCL L779 5770b40 050L2b5 7T3 m
MSS STANDARD PRACTICE SP-92
5. INSTALLATION c) Check the valve for any marking indicatin
flow direction. Make sure that the valve is ir,
5.1 Introduction stalled in the proper flow orientation when a
flow direction is indicated on the valve.
5.1.1 ? oint in time in the life
of an industrial valve is the momentof instal- d) Inspect the valve interior to the extent prac-
lation. The possibilities for degradationof the tical through the end ports. Make sure it is rea-
valve are numerous. Conversely, the exercise sonably clean, free from foreign matter and
of proper care in this process will assure in- harmful corrosion. Remove any special pack-
creased probability of trouble-free valve ser- ing materialssuch as blocks used to preventdisc
vice. movement during shipping and handling.
5.1.2 The valve industryhas prepared thisSec- e) If practical, actuate the valve through an
tion in order to provide useful information, open-close-open or clos"e-open-close cycle. In-
warnings and reminders, in ? spect anysignificant functional features such as
be helpful to all concerned.A judicious selec- guides orseat faces that are made accessible by
tion of these pages, delivered to the installa- such actuation. Caution: Avoid contact with the
tion site with the valve itself, will providethe valve closure element during cycling. Itis usu-
opportunity for the person havingthe greatest ally desirable to leave the valve closure mem-
need to know to be informed or reminded of ber in the position in which it was shipped fol-
what is most important at the time such infor- lowing such inspection.
mation can be the most useful.
f) Check the piping to which the valve is to be
5.2 Insoection fastened for proper alignment, cleanliness ant
freedom from foreign materials immediatel;
5.2.1 The testing and inspection required by prior to valve installation.
applicable standards and specifications make
it generally reasonable to assume that ? Valve- Pipe Assembly
valve, about to be installed in ? tem, has been properly designed and manu- 5.3.1 Threaded pipe jointsdepend on ? tured. Nevertheless, it is important to rec- between the external and internal pipe threads
ognize that in the transport, handling andstor- for tight sealing. Usually, ? or
age of ? he time of manufac- viscous material is used betweenthe assembled
ture and the time of installation, there are nu- threads to assist in ensuring ? The
merous possibilitiesfor accident or error which following installation practices are recom-
could adversely affect valve performance. mended:
5.2.2 It is therefore important to determine a) Check the threads on both the valve and the
that the valve is in satisfactory condition be- mating pipe for correct thread form and clean-
fore installation.The following pointsare gen- liness. Be alert for any indication of an impact
erally applicable and may be helpfulin avoid- that might havedeformed the thread either out-
ing subsequent valve problems. of-round or by ? on. Be sure no
chips or grit are present.
a) Carefully unpack the valve and checktags
or identification plates, etc.against the bill of b) Note theinternal length of the threads in the
material. specifications, schematics,etc. valve ends and theproximity of the valve inter-
nal seat to make sure the pipe end will not hi
b) Make ? any special warn- the seat when assembled. If there appears to lx
ing tags or plates attached to or accompany- ? ully check the
ins the valve and take any appropriate action. pipe end thread to make sure thereis no extended
straight portion beyond the standard tapered
section.
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STD-MSS SP-92-ENGL L999 5770b40 05012bb b3T m
MSS STANDARD PRACTICE SP-92
c) Apply an appropriate thread tapeor thread b) Check the bolting for proper size, length,
compound to the external pipe threads except and material. ? lt ona high tem-
when dry seal threading is specified. Avoid perature flange joint can result in early joint
getting the thread tape or thread compound into failure.
the internal flow area.
High strength material is always requiredfor
d) Use care to align the threads at the point of flange bolting on steel flanges Class 400 or
assembly. Tapered pipe threads are inherently higher. Such bolting is usually stamped “B-7”
a loose fitat entry. Substantial wrenching force on the end but other grades may be used in
should not be applied until it is apparent that some cases. The proper matching of flanges,
the threads are properly engaged. bolting and gaskets is important. Specific re-
quirements of ASME ? satis-
e) Assemble the joint wrench-tight. The fied.
wrench on the valve should be on the valve
end into which the pipe is being threaded. Low strength bolting may be used for lower
Courion: Because there is no clear limit on pressure flanges, Classes 150 and 300 for op-
the torque that may be developed in ? temperatures not exceeding400 “F(204
thread joint, it is possible to damage the valves “C), whenusing approved gaset materials.See
or piping byapplying excessive twisting forces ASME ? specification.
through the body of the valve.
c) Gray iron flanges are less “forgiving” of
f) Repeat the process at the second valve end. improper installation than flanges of ductile
Again, apply the wrench at end of the valveto materials. The use of lower strength steel bolt-
which the pipe is being assembled. ing is recommended for gray iron flanges to
reduce the possibility of overstressing the
5 .4 Flanged Joint Assemblv flanges by excessive bolt preload. Full face
gaskets on flat flanges provide desirable pro-
5.4.1 Flanged joints depend on compressive tectionagainst flange breakage by
deformation of the gasket material betweenthe overtorquing of the flange bolts. ? cing flange surfaces for tight sealing. The flange should not be installed againsta raised
mechanical force necessary to maintain the face flange.
compressive stresses on the gasket,as well as
resist the normal pressure forces tending to Good preassembly alignment is especially
separate the joint, must be provided by the important in gray iron flange joints to ensure
bolting. It should be recognized that with that adequate gasket compression can be
“brute force” alignment of misaligned flanges, achieved without excessive bolting loads.
sufficient bolting force may not be available
to sustain the required gasket loading and to d) Check the gasket materials. See ASME
resist the load caused by the pressureseparat- ? onal requirements for flange
ing force, resulting in ? roblem. joints using low strength bolting, (e.g., gray
The following practices should be observed iron flanges or Class 150 steel flanges.) Metal
for satisfactory flange joint make-up. gaskets (flat, grooved, jacketed, corrugated,or
spiral wound), should not be used with these
a) Check the mating flange facings. Do not flanges.
attempt to assemble the flanges if ? found which might cause leakage (e.g., ? skets for freedom from injuri-
deep radial groove cut by ? ing ous defects or damage.
tool or ? face caused by mis-
handling), until the condition is corrected. f) Use care to provide good alignmentof the
flanges being assembled. Use suitable lubri-
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MSS STANDARD PRACTICE SP-92
cants on the bolt threads. Sequence the bolt cross sectional area than the pipe.
tightening to make the initial contact of the
flanges and gaskets as flat and parallel as pos- 5.5.2 Butt weldsjoints require full penetration welds
sible. Tighten the bolts gradually and uni- and ? at least equal to thatof the pipe.
formly to avoid the tendency to twist one Welding ? alloy to ? relative to the other. Use of ? material of lower mechanical strength re-
wrench is helpful to ensure correct and uni- quires that the weld taper to ? eater
form final tightening of the flange bolting. thickness at the valve end. An alternative would be
to have ? trength “weld-on extension”
Parallel alignment of flanges is especially im- or “pup” welded to the valve prior to welding in the
portant when assembling ? x- line.
isting system. It should be recognized that"if
the flanges are not parallel, then it will be nec- 5.5.3 Soundwelds are obviouslyimportant. Cm-
essary to bend something to make the flange rion: this guide is not ? instruc-
joint tight. Simply forcing the flanges together tion. All welding should be in accordance with any
with the bolting may bend the pipe or it may ’Code or jurisdictional regulations applicable to the
bend the vulve. This is particularly truein large construction of the piping system. The welds must
diameter piping. Such conditions should al- be made following approved welding procedures and
ways be brought to the attention of someone be inspected as requiredby all applicable specifica-
capable of evaluating the bending condition tions. The following points are intended to be help-
and the corrective measures that need to be ful as point-of-use reminders of important require-
taken. ments of good welding practice:
The assembly of certain “wafer type”or “short a) Consult the manufacturer forthe correct installa-
pattern” valves between mating flanges re- tion procedure of ? lve prior to pre-
quires that the installation be checked for any heatins, welding and post weld heat treatment of a
possibility of interference between the mov- butt weldor socket weld valve.To avoid the possibil-
ing parts of the valve and the adjacent pipe, ity of arcing between the yoke bushing, stem, disc
fitting, or valve. andor seats, always attach the ground directlyto the
body.
g) Cuurion: Torque wrenches should always
be used to assure proper tightening of the b) Consult the manufacturer forthe correct installa-
flange bolting. If, in the tightening process, tion procedure before weldinga soft seated valve into
the torque on ? been increasing ? ballor plug valve
with each part turn and then is observed to should be in the full open position prior to welding
remain unchanged or increase ? preventseat damage andor weld splatter fromad-
amount with an additional part turn, that bolt hering to the ball or plug. ? ng the
is yielding. That bolt should be replaced and ball cavityis recommended to relieve any fluidpres-
scrapped since it is no longer capable of main- sure that might developedue to thermal effects.
taining the proper preload.
c) Check materials marking on the pipe and valve to
5.5 Weld Joint Assemblv confirm that they are as specified.
5.5.1 Welded joints that are properly made d) Inspect the welding end surfaces for dimensions
provide ? metallurgical conti- and cleanliness.Correct any condition that might in-
nuity between the pipe and the valve body. It terfere with assembly and satisfactory welding.
is important that the joint should not consti-
tute ? weak link” in the pipe-valve- e) Check all backing rings that may be used tocon-
pipe assembly. Therefore, the weld fillet for firm that the ring materialis compatible with thepipe
socket weld joints must always have more and valve materials and that the individual rings fit
and are clean.
COPYRIGHT Manufacturers Standardization Society of the Valve8 and Fittings
Licensed by Information Handling Services
~~ ? P-92-ENGL L999 ? 402 m
MSS STANDARD PRACTICE SP-92
flushing fluid may settle in such cavities and
f) Determine that all required welding param- adversely affect valve operation. Also, abra-
eters, including preheating and post weld heat sive material camed by ? luid
treating, are in accordance with the approved stream may cause serious damage to seating
welding procedure. surfaces.
g) Inspect the “valve to pipe end” alignment
and adjust as required. 6. OPERATION AND MAINTENANCE
h) Securely tack weld the mating parts when 6.1 Introduction
required if part of the approved procedure.
6. l.1 An industrial valve, reasonably matched
i) Complete the weld using the approved weld- to ? ice application and prop-
ing procedure. erly installed in ? can be ex-
pected to havea long service life with ? an and inspect the finished weid. mum ofattention. Unlike totally passivecom-
ponents such as pipe fittings, vessels, etc.,
k) Repair any defects using an approved weld valves area special kind of “machinery” hav-
repair procedure when necessary. ing moving and wearing parts. The satisfac-
tory performance of these working parts de-
5.6 Testing and Adiustment pends on the long tem preservation of vari-
ous highly finished surfaces. Therefore, it is
5.6.1 It is reasonable to assume that ? to give adequate attention to the
that has been properlyinspected and installed specific requirements for proper operationand
will be in good condition and ready to oper- reasonable maintenance of all valves through-
ate. However, theactual operability of ? service life.
can only be provedby test.
6.2 Operation, Manual Valves
5.6.2 ? ustable stem packing
should be checked to determine that the pack- 6.2.1 Most valves are actuated manually by
ing has been properly installed and the gland causing some linear or rotational movement
bolting has the correct initial adjustment be- of ? ch, handle, etc. Care is
fore testing the system. ? on can required to assure that such movement is in
be made by actuating the valve through an the correct direction, is not too fast or too slow
open-close-open or close-open-close cycle. and is applied through the proper distance.The
Packing glandbolt tightness shouldbe checked terminal positions, open and/or closed, have
and bolts should be retightened if necessary. important functional significance. This is
If no obvious problems are observed, an ac- particulatly true in the closed pbsition where
tual test at pressure may then be made while the internalclosure element (disc, plug, sphere,
the stem packing tightness and operability of etc.) must be correctly positioned in relation
the valve is checked. Gland bolts should be to the seat to assure ? br>retightened if packing leakage is observed.
6.2.2Valves in which the closure element
5.6.3 It is common practice after the installa- moves to and from theseat, such as in globe,
tion of ? clean the system by angle, diaphragm and wedge gate valves, de-
blowing through the system withgas aor steam pend to some degree on the mechanical force
or flushing with aliquid to remove debris and of the stem holdingthe closure element against
or internal protective films and coatings. It the seat to make and maintain ?
should be recognized that valve cavities may This is most important if the line pressure to
form ? ? nd be shut off acts on the closure element in a
material not dissolved or carried out by the direction so as to push it off the seat. When
COPYRIGHT Manufacturers Standardization Society of the Valve and 9Fittings
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globe type valves are installed so that the line 6.2.6 Thermal expansion and contraction can
pressure then acts in the same direction as the cause solid wedge gate valves to “lock up” if
stem forceand also in wedge gatetype valves, closed while hot. As the relative cooler stem
the line pressure then acts to increase theseat- heats up to body temperature, and/or the body
ing loadmaking valve stem loading lesscriti- cools down toward the stem temperature, the
cal. However, substantial stem force will still stem expansion and/or body contraction will
be required at low line pressures. The stem cause stem thrust to increase. If the thrust in-
force may even be more important at low line creases sufficiently, the wedge may be
pressures than at high line pressures. “locked” between the tapered seats.
6.2.3 Globe type valves (straight, angleorY- 6.2.7 Certain valve stems are provided with a
pattern) and stop check valves with pressure backseat arrangement, that is ?
under the disc, require sufficient stem loading stem or on another part of the stem-disc as-
to balance the line pressure and provide ad- sembly, that engages ? eat
equate net seat load. The higher the line pres- shoulder on the inner side of the bonnet.
sure, the higher the required stem loading to
achieve ? Follow the 6.2.8 It has become generally recognized that
manufacturer’s recommendationson torque or the use of the stem backseat for stem sealing
handwheel rim force for seating of manually may mask an unsatisfactory condition of the
operated valves as well as impacting of im- stem packing. For this reason, the use of the
pactor-type handles or handwheels. Caution: backseat for normal operational stem sealing
The useof valve wrenches on handwheels may is not recommended. It is recommended that
lead to valve damage or injury to operators. the valve beopened against the backseat as a
See Section 6.3 for information relative to means of determining that the full open posi-
valves with power actuators. tion has been reachedand the stem should then
be backed off slightly from the backseat.
6.2.4 Most valves in which the internal clo-
sure element slides across the seat as in ball, 6.2.9 If circumstances necessitate use of the
plug, non-wedging gates, butterfly etc.,do not backseat for stem sealing to permit system op-
rely on stem actuating force to provide tight eration until ? llow replace-
shut-off. However,the correct position of the ment of the stem packing, it should be recog-
closure element in these typesof valves is very nized that backseats are usually muchsmaller
important. In some cases the effort required than “mainseats” and care should be exercised
to move the closure element may increase sub- to avoid applying excessive stem force in
stantially during final approach to the closed backseating. Impactors, gears, or similar fea-
position, giving ? of having tures provided to assist in mainseating valves
reached the required position. Failure to get should not be used for backseating.
to and stop at thefull closed position can re-
sult in leakage and consequent damage to the 6.2.10 Caution: Some users consider that
sealing elements. backseats are provided for the purpose of re-
packing valves which are under pressure.
6.2.5 Ball, plug, butterfly, and non-wedging When the packing is removed inthis situation,
gate valves require correct positioning of the any leakage past the backseat escapes directly
closure element to seal properly. Closing trave1 to the atmosphere and constitutes ? ould not stop until ? reached safety hazard to personnel. The practice of
or ? tor reaches the “closed” repacking under pressure is not recommended.
position mark. Caution: Some non-wedging Further, if ? in the backseated
gate valves require the closure element to be position for any reason, exercise caution when
backed off slightly from the positivestop po- moving the stem away from the backseat as
sition to allow the closure element freedom to the packing may havedeteriorated while iso-
move.
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~~ ~
~~ ~
STDmMSS SP-92-EMGL L999 I5770b40 0503270 Oh0 m
MSS PRACTICE STANDARD SP-92
lated from the line fluid and then leak when tions for reduced voltages shouldalso be con-
exposed to pressure. sidered.
6.2.1 ? ications requiring re- d) Pneumatic pressure availablefor pneumatic
strictive maximum forces to be appliedon le- actuators (cylinders or diaphragms). Also,
vers or handwheel rims may also lead to dam- specify fail-open, fail-closed, fail-as-is,or any
aging forces being applied to valvesor actua- special requirements.
tors in actual practice as larger forcesare some-
times applied in the field. Users should con- e) Requirements for position indication sig-
sider this fact in training ofoperating person- nals.
nel.
6.3.3 Actuator selectionand adjustments
6.3 ODeration. Power Actuated Valves should normally be made by the valve manu-
facturer based on published literature andor
6.3.1 Functionally,closure performance char- technical advice of actuator manufacturer. The
acteristics and backseating considerationsare valve manufacturer should be consultedwhen
associated with all valve types regardless of ? ed valve must be retrofitted
the means of operation. Satisfactory valve per- with ?
formance with power actuation requires ap-
propriate programming of the various re- 6.3.4 Backseating valves should be adjusted
quirements and constraints into the actuator to stopslightly below the backseated position.
controls. Therefore, the actuator should be
adjusted to deliver an adequate opening,run- 6.3.5 Caution: Some valve actuators, when
ning and closing force to suit the anticipated sized to provide specified loading, may have
service conditions and the valve type. For the much higher output at maximum switch or
position-sensitive valve types, the close con- control settings and therefore be capable of
trol should be position controlledby external damaging valves if misadjusted. Valve and
stops or limit switches. actuator manufacturers instructions should be
followed closely to prevent overloading valve
6.3.2 Data required for selection and adjust- stems, backseats and other structural parts.
ment of power actuators shouldbe delineated Successful operationof power operated valves
clearly in purchase specificationsfor actuated requires ? nation of the skills
valves. This data shall include but not neces- and efforts of the valve specifier, the valve
sarily be limited to: manufacturer and the actuator manufacturer.
Most applications are problem-free, but mis-
a) Upstream pressure and differential pres- communication can lead to unreliable opera-
sure conditions at which both opening and tion at one extreme and possible valve or ac-
closing shall be required. Specifydirection if tuator damage at theother extreme.
applicable. Additionally, specify if valve op-
eration is requiredunder high-flow 6.4 Fluid Dvnamics of Shut-off Valve Operation
“blowdown” conditions.
6.4.1 ? as
b) Speed of operation required or the maxi- mass and velocity. Anything that causes a
mum time for opening and/or closing. Also, moving mass to change its velocity will expe-
specify ? required due to fluid rience ? force in proportion to
dynamics (see Section 6.4). the magnitude of the mass and the rate of the
imposed velocity change.
c) Electrical power supply available (AC or
DC; voltage, phase, frequency) for electrical 6.4.2 However, inthe flow of gases the react-
power actuators or controls. Operatingcondi- ing inertia forces are inherently moderatedby
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COPYRIGHT Manufacturers Standardization Society of the Valve and Fittings
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the compressibility of the fluid which permits limits on speed of closure should be consci-
the instantaneous velocity changeto be effec- entiously observed.
tively limited to the mass of fluid in the im-
mediate vicinity. This,in addition to the self- 6.4.7 Rapid closure of ? owing
cushioning capacity of the fluid column in the liquid pipeline can cause ? s-
upstream pipe, effectively precludes any Sig- sure surge whichmay manifest itself in ? nt problem of pressure surge in rapidly “bang” or possiblya series of “bangs”. This is
closed valves in gaseous fluid piping. frequently referred to as water hammer. This
phenomenon can occur in any flowing liquid
6.4.3 In contrast, the inertia of the fluid col- line and is not limited to water lines. Rapid
umn in ? is not so easily over- closing of ? in ? br>come. Its relative incompressibility provides line should be avoided especially during the
no suchcushion or proximity-limiting mecha- last part of the stem travel.
nism. The entire upstream fluid mass is re-
quired to be decelerated at once by the clos- 6.5 Check Valves
ing valve and the resulting pressuresurge may
be of sufficient magnitude to cause structural 6.5.1 Check valvesare one-way valves that func-
damage. tion to automatically stop ? a
flowing line. Therefore,in most applications, the
6.4.4 An additional potential problemcan oc- fastest possible closure is desirable. The speed
cur downstream from the closing valve. This of closure is understood in terms ofthe shortest
may be described as fluid column rupture and possible time to achieve closure following the
involves theinertia of the fluid columncarry- instant of flow reversal. It follows then, that the
ing it away from the closed valve with the shorter that time interval be can made, the lower
proximate space being occupied by ? city of the reverse flowing liquid will
of the fluid vapor or, simply, ?
vacuum. If there is sufficient backpressure in
the line, the fluid column will reverse its ve- 6.5.2 The pressure surge resulting from a
locity and close the void created by the fluid check valve closure is likely to be more se-
column rupture and cause another pressure vere than that in the case of the shut-off valve
surge when it reaches the valve. as the shut-off valve will usually provide a
throttling action, while the check valve clo-
6.4.5 It should be recognized that pressure sure may be virtually instantaneous with little
surge intensity is roughly proportional to the preliminary throttling.
length and velocity of the fluid column up-
stream ofthe closing valve and inversely pro- 6.5.3 ? sure can also cause
portional to the time taken toclose the valve. downstream fluid column rupturejust as in the
Fluid column rupture and return surge inten- case of shut-off valves. Furthermore,on fluid
sity is proportional to the same condition on column reassembly,the pressure surgemay be
the other side of the valve in addition to the of sufficient magnitude to reopen the check
back pressure in that sectionof piping. There- valve, starting another sequence of closure,
fore, ? helpful in limiting the surge, etc. Under certain conditions ? de of the pressure surgephenomena. tracted successionof closure “hammers” may
result.
6.4.6 In large long distance liquidpipelines it
is critically important to evaluate pressure 6.5.4 The kinetic energy in flowing fluids pre-
surge possibilities and to establish limits on sents special problems regarding check valve
the speedof closure of the flow shut-off valves. performance. Quick closing is normally de-
In operating such valves or setting the speed sirable, but special features may be required
of operation of power actuated valves,design for certain situations. Careful systems analy-
sis may be required in complex applications.
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COPYRIGHT Manufacturers Standardization Society of the Valve and Fittings
Licensed by Information Handling Services
STDmMSS SP-92-ENGL 5999 5770b40 0503272 733 9
MSS STANDARD PRACTICE SP-92
velocity of flow. There may bea “wind” noise
6.5.5 While ? ne. There may be clear or
is normally the best method of minimizing hoarse whistling sounds resulting from the
pressure surges due to flow reversal,some ap- shape of the flow passage, includingthe flow
plications produce flow reversals that are too path througha valve. Cavitatingconditions in
rapid to prevent excessive reverse velocity ? cause ? that
before the closure of ? valve ranges from ? ocks
could occur. Such applications may require and gravel, toa deafening roar. There mayalso
consideration of special valve features suchas: be mechanical noisesas ? ent
of intemal “things” acted on by the flowing
a) ? ofother loading to pro- fluid. Some of these noises may be relatively
vide more rapid closing, harmless insofar as system integrity and per-
formance are concerned. Mechanicaldamage
b) ? ber to provide ? with compressible fluid is generally
more controlled closure to reduce reverse flow limited to pointsof sonic or supersonic veloc-
velocity by ? on as in ? wherea vortex resonance withan inter-
valve. nal component causes movement and wearor
breakage.
6.6 Ouarter Turn Valves
6.7.2 Vortex resonance withan internal com-
6.6.1 ? or closing torque may ponent may also cause problems in liquid ser-
be produced in some valves actuated by rota- vice. In addition, noise may be evidence of
tion of ? tation which hasthe potential for causing
to the distribution of fluid pressure on the clo- mechanical damage, including massive ero-
sure element. Such ? nly open sion ofthe metal walls ofa valve or pipe walls
or close itself if not forcefully restrained. As and/or other internal components.
previously noted, ? ction can
produce ? urge or “hammer” 6.7.3 ? discussion of allof the
that is potentially capable of causing structural sound-generating mechanisms is beyond the
damage. scope of this document. Nevertheless,it is rec-
ommended that an evaluationbe made ofany
6.6.2 An additional point of concern is the condition of remarkable noisein ? possible injury to personnel operating the tem at least to the point of understanding its
valve. The person may grasp an operating cause. If ? ed, ? r>handle and start to moveit only to haveit sud- should be madeas to whether the valveis the
denly slam to the open orclosed position. This source or just happens to be the location of
can result in ? depending on the noise. Usually, if the valve is the source,
how the person is positioned and how the the noise can be “tuned” by slightly “throt-
handle is grasped. Care should always be ex- tling” the valve.
ercised in operating ? lve that
is not equipped with self-locking gearing or 6.7.4 Mechanical or high intensityfluid noise
other substantial stem restraints. Serious con- in the vicinity of ? r>sideration should be given to the possibility potentially serious trouble. Expert assistance
that the operating handle may suddenly slam should be obtained from systemengineers or
to the open or closed position. the valve manufacturerto determine the cause
6.7 Noise and evaluate possible need for action.
6.7.1 There are many different valve operat- 6.7.5 Noise emitted from ? a
ing conditions that can result in noise. Such special case that may indicate seat leakage re-
noise may be “normal” considering the nature quiring repair. ? may indi-
of the fluid and the pressure, temperature and cate sever erosion of seating surfaces while
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COPYRIGHT Manufacturers Standardization Society of the Valve and Fittings
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~~ ? D-MSS SP-92-ENGL L997 ? 87T m
MSS STANDARD PRACTICE SP-92
“gurgling” or “popping” sounds may signify agnostics systems can be used to augment the
less severe leakage. evaluation of the noise. Periodic disassembly
and internal inspectionof selected valves may
6.8 Maintenance be advisable, particularly where they are lo-
cated close to upstreamflow disturbances (see
6.8.1 Valves are properly considered to be ? r>hybrid structure, ? ssel and operating mechinery. Maintenance 6.8.5 Stem seals may be ?
procedures therefore, must reflect therequire- lems, particularlyin valves that are frequently
ments of the occasional opening or closing of cycled or must operate at high pressures or
the “machinery” and the predominant operat- temperatures. The stem seal must prevent or
ing condition of the valve where pressure is minimize leakage of linefluid between ? ously applied and nothing is moving. able stem anda stationary bonnet.While spe-
The important performance parameters are cial mechanical arrangements,elastomers, or
pressure boundary integrity, actuating effort proprietary seals are used in some cases, the
required and internal leak tightness. Mainte- normal arrangement includes ? nance should logically address the importance chamber in the bonnet surrounding the stem,
of preserving these performance parameters. with compression packing material retainedin
the chamber by ? iated bolt-
6.8.2 Valves which remain in one positionfor ing.
long periods of time may be hard to aperate
and/or not function as well as when originally 6.8.6 Conventional compression packing re-
installed. This reduction of operability can quires that the gland boltingprovide sufficient
result from either ? ve lubricants load to eliminate any communicating poros-
in the stem threads, aging of packing,surface ity in the packing material and to compress it
corrosion of moving parts, or an accumula- into intimate contact with the stem and bon-
tion of deleterious solids. In some applications net. Clearances between the associated parts
it may be desirable to schedule periodic par- must be close enough to contain the packing
tial or full cycle exercising of such valves. material and minimize extrusion. Maintenance
practices that increase clearances(e.g. machin-
6.8.3 Check valves require special consider- ing of glands and/or bonnets to remove corro-
ation because they normally have noexternal sion) may result in packing extrusion and leak-
stems, actuators, or packings that might indi- age or “blowout”.
cate ? onal problem. Complete
internal failure may occur due to wear with 6.8.7 Pressure boundary integrityrequires ba-
no obvious advance warning. Preventive main- sically sound pressure containing parts,a pres-
tenance is recommended particularly where sure tight static seal at assembly joints andin
sudden check valve failuremay require expen- most cases, an effective workingseal between
sive plant or system shutdown. ? the valve bonnet. Mainte-
nance ofpressure boundary parts and the static
6.8.4 Noise or vibration emitted at or near ? joints is not usually consid-
closed check valve maybe an indicator of leak- ered to be ? r, continuous
ase (see Section 6.7). Distinctive noises may monitoring is recommended to confirm that
also be produced from internal motion of the problems do not occur.The need for paint pro-
parts of check valves that are not fully open tection against corrosion of exposed piping
during forward flowing conditions. “Thump- should be obvious from normal observations
ing” or ”tapping” may indicate that the disc is of the system.
impacting either on the seat or the full-open
stop, or simply “rattling” in its guides. These 6.8.8 Wear and loss of packing material are
types of conditions can lead to rapid wearand normal expectations in frequently cycled
failure of the valve. Special non-intrusive di- valves. However, current packing materials
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STD*MSS SP-92-ENGL L999 5770640 0503274 706 m
MSS STANDARD PRACTICE SP-92
and systems will minimize this deterioration, borne grit, chemicals or moisture. Working sur-
particularly in new and well-maintained faces suchas stem threads, bearings, and gears
valves. Packing gland adjustmentmay be nec- should be lubricated on ? dule
essary from time to time but routine “repack- using the lubricants recommended or approved
ing” should not be required in most valves that by the valve or actuator manufacturers.
are otherwise well maintained. Packing re-
placement can usually be deferred until ? ntenance of valves must involve a
when other valve maintenance is required as good preventive maintenance program, particu-
long as the packing gland shows adequate larly for check valves and valves in severe throt-
room for further adjustment. See Section 6, tling service. Stem sealing problems may be
Paragraph 6.2.10 regarding the hazards to per- alleviated by use of the newest technology in
sonnel involved in repacking ? design, packing materials and installation
valve under pressure. This practice is not rec- procedures.
ommended.
6.8.9 Valve manufacturersand packing manu-
facturers should be consulted regarding the
best design features and compression packing
materials available to solve chronic packing
problems. Ongoing developments in valve
design and packing technology mayoffer im-
provements that can be implemented by ret-
rofitting ? oved designs, ma-
terials and installation procedures. For ex-
ample, spacers may be used in deep packing
chambers common in old valves that were de-
signed for usewith old style asbestos packings
so that new packings/materials may be effec-
tively installed.
6.8.10 Severe throttling service may cause the
valve to be subjected to damage of the seating
surfaces and other parts. Severe cavitation can
cause gross damage of the internal parts, in-
cluding the valve body and downstream pip-
ing. Good preventive maintenance procedures
including periodic inspections,may prevent se-
rious failures which require expensive shut-
downs. Methods of evaluation and solutions
for maintenance problems are beyond the
scope of this Guide. Valve manufacturers
should be consulted concerning design fea-
tures and operating procedures for valves.
6.8.1 ? mechanisms, actuators
and accessories are generally readily acces-
sible for inspection and maintenance. Reason-
able protection should be provided to prevent
mechanical damage and potentially degrading
environmental exposure to such things as air-
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ANNEX A
REFERENCED STANDARDSAND APPLICABLE DATES
This Annex is an integral part of this StandardPractice which is placedafter the main text for convenience.
Standard Name and Designation
ASME. ANSYASME. ANSI. ASMmANSI
B16.33-1990 Manually Operated Metallic Gas Valves for Use inGas Piping Systmes
B16.34-1996 Valves ? ed and Welding End
B16.5-1996 Pipe Flanges and Flanged Fittings
-API
API 6D ? ion for Pipeline Valves, End Closures,Connectors and Swivels
API 589- 1993 Fire Test for Evaluation of Valve Stem Packing
API 594- 1991 Wafer Check Valves
API 599- 1994 Steel Plug Valves, Flanged or Buttwelding Ends
API 600- 1996 Steel Gate Valves, Flanged and Buttwelding Ends
API 602- 1993 Compact Steel Gate Valves
API 603- 1991 Class 150, Cast, Corrosion-Resistant. Flanged-End Gate Valves
API 607- 1993 Fire Test for Soft Seated Quarter Turn Valves
API 609- 1991 Butterfly Valves, Lug Type and Wafer Type
MSS
MSS SP-42- 1990 (R93 class 150 Corrosion Resistant Gate, globe, Angle and Check Valves with
Flanged and butt WeldEnds
MSS SP-45-1992 Bypass and Drain Connections
MSS SP-67- 1995 Butterfly Valves
MSS SP-68-1997 High Pressure ? terfly Valves
MSS SP-70- 1990 Cast Iron Gate Valves, Flanged and Threaded Ends
MSS SP-7 1- 1990 Cat Iron Swing check Valves, Flanged and Threaded Ends
MSS SP-72-1992 Ball Valves with Flanged or Butt-welding Ends for General Service
MSS SP-78-1987 (R92) Cast Iron Plug Valves, Flanged and threaded Ends
MSS SP-80- 1997 Bronze Gate, Globe, Angle and CheckValve
MSS SP-81-1995 Stainless Steel, Bonnetless, Flanged Knife Gate Valves
MSS SP-85-1994 Cast Iron Globe ? langed and Threaded Ends
MSS SP-88-1993 Diaphragm Type Valves
MSS SP-91-1992 (R96) Guidelines for Manual Operation of Valves
NACE
MRO 175-97-1997 Sulfide Stress Cracking Resistant Metallic Materialsfor Oilfield Equipment
16
COPYRIGHT Manufacturers Standardization Society of the Valve and Fittings
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STD.HSS SP-92-ENGL 1999 ? 589 a
MSS STANDARD PRACTICE SP-92
Publications of the following organizations appear in the above list:
API American Petroleum Institute
1220 L. Street, N.W., Washington, D.C.20005
ASME American Society of Mechanical Engineers
3 Park Avenue, New York, NY 10016-5990
MSS Manufacturers Standardization Society of the Valve and Fitting Industry, Inc.
127 park Street, N.E., Vienna, VA 22180
NACE NACE International
P.O. Box ? TX 772 18-8340
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COPYRIGHT Manufacturers Standardization Society of the Valve and Fittings
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List of MSS Standard Practices
(Price List Available Upon Request)
Number
SP-6-1996 Standard Finishes for Contact Faces of Pipe Flanges and Connecting-End Flanges of Valves and Fittings
SP-9-1997 Spot Facing for Bronze, Iron and Steel Flanges
SP-25-1998 Standard Marking System For Valves, Fittings, Flanges and Unions
SP-42-1999 (R 95) Class 150 Corrosion Resistant Gate, Glove, Angle and Check Valves with Flanged and Butt Weld Ends
SP-43-1991 (R 96) Wrought Stainless Steel Butt-welding Fittings
SP-44-1996 Steel Pipeline Flanges
SP-45-1998 Bypass and Drain Connections
SP-51-1991 (R 95) Class 150LW Corrosion Resistant Cast Flanges and Flanged Fittings
SP-53-1999 Quality Standard for Steel Castings and Forgings forvalves, Flanges and Fittings andOther Piping Components ? le Examination Method
SP-54-1999 Quality Standard for Steel Castings for Valves, Flanges, and Fittings and Other Piping Components ? amination Method
SP-55-1996 Quality Standard for Steel Castings forValves, Flanges and Fittings and Other Piping Components -Visual Method for Eval. of Surface Irregularities
SP-58-1993 Pipe Hangers and Supports ? gn and Manufacture
SP-60-1999 Connecting Flange Joint BetweenTapping Sleeves andTapping Valves
SP-61-1999 PressureTesting of Steel Valves
SP-65-1999 High Pressure Chemical Industry Flanges and Threaded Stubs for Use with Lens Gaskets
SP-67-1995 Butterfly Valves
SP-68-1997 High Pressure Butterflyvalves with Offset Design
SP-69-1996 Pipe Hangers and Supports ? pplication
SP-701998 Cast Iron GateValves, Flanged andThreaded Ends
SP-71-1997 Gray Iron Swing CheckValves, Flanged andThreaded Ends
SP-72-1999 Ball Valves with Flanged or Butt-weldingEnds for General Service
SP-73-1991 (R 96) Brazing Joints for Wrought and Cast Copper Alloy Solder Joint Pressure Fittings
SP-75-1998 Specification for High Test Wrought Butt Welding Fittings
SP-77-1995 Guidelines for Pipe Support Contractual Relationships
SP-78-1998 (R 92) Cast Iron PlugValves, Flanged andThreaded Ends
SP-79-1999a Socket-Welding Reducer Inserts
SP-80-1997 Bronze Gate, Globe, Angle and Checkvalves
SP-81-1995 Stainless Steel, Bonnetless, Flanged, Knife GateValves
SP-82-1992Valve PressureTesting Methods
SF-83-1995 Class 3000 Steel Pipe Unions, Socket-Welding and Threaded
SP-85-1994 Cast Iron Globe ? anged andThreaded Ends
SP-86-1997 Guidelines for Metric Data in Standards forvalves, Flanges, Fittings and Actuators
SP-87-1991 (R 96) Factory-Made Butt-welding Fittings for Class ? Applications
SP-88-1993 Diaphragm Typevalves
SP-89-1998 Pipe Hangers and Supports ? Installation Practices
SP-90-1986 (R 91) Guidelines on Terminology for Pipe Hangers and Supports
SP-91-1992 (R 96) Guidelines tor Manual Operation ofvalves
SP-92-1999 (R 92) MSS Valve User Guide
SP-93-1999 (R 92) Quality Standard for Steel Castings and Forgings forvalves, Flanges, and Fittings and Other Piping Components ? Examination Method ~
SP-94-1999 Quality Std for Ferritic and Martensitic Steel Castings for Valves, Flanges, and Fittings and Other Piping Components ? ination Method A
SP-95.1999 (R 91)Swage (d) Nipples and Bull Plugs
SP-96-1996 Guidelines onTerminology for Valves and Fittings
SP-97-1995 Integrally Reinforced Forged Branch Outlet Fittings ? Threaded and Buttwelding Ends
SP-98-1996 Protective Coatings for the Interior ofValves, Hydrants, and Fittings
SP-99-1994 Instrument Valves
SP-100-1997 Qualification Requirements for Elastomer Diaphragms for Nuclear Service Diaphragm Type Valves
SP-101-1989 Part-Turn Valve Actuator Attachment ? ing Component Dimensions and Performance Characteristics
SP-102-1969 Multi-Turn Valve Actuator Attachment ? ing Component Dimensions and Performance Characteristics
SP-103-1995 Wrought Copper and Copper Alloy Insert Fittings for Polybutylene Systems
SP-104-1995 Wrought Copper Solder Joint Pressure Fittings
SP-105-1996 Instrument Valves for Code Applications
SP-106-1990 (R 96) Cast Copper Alloy Flanges and Flanged Fittings, Class 125, 150 and 300
SP-107-1991 Transition Union Fittings for Joining Metal and Plastic Products
SP-106-1996 Resilient-Seated Cast Iron-Eccentric Plug Valves
SP-109-1996 Welded Fabricated Copper Solder Joint Pressure Fittings
SP-110-1996 Ball ValvesThreaded, Socket-Welding, Solder Joint, Grooved and Flared Ends
SP-111-1996 Gray-Iron and Ductile-IronTapping Sleeves
SP-112-1999 Quality Standard for Evaluation of Cast Surface Finishes ? le Method. This SP must be sold with ? three-dimensional Cast Surface Comparator, which is ? of the Standard.
Additional Comparators may be sold separately at $19.00 each. Same quantity discountsapply on total order.
SP-113-1999 Connecting Joint betweenTapping Machines andTapping Valves
SP-114-1995 Corrosion Resistant Pipe FittingsThreaded and SocketWelding, Class 150 and 1000
SP-115-1999 Excess Flow Valves for Natural Gas Service
SP-116-1996 Service Linevalves and Fittings for Drinking Water Systems
SP-117-1996 Bellows Seals for Globe and Gate Valves
SP-118-1996 Compact Steel Globe ? ngeless,Threaded &Welding Ends (Chemical ? ery Service)
SP-119-1996 Belled End Socket Welding Fittings, Stainless Steel and Copper Nickel
SP-120-1997 Flexible Graphite Packing System for Rising Stem Steel Valves (Design Requirements)
SP-121-1997 QualificationTesting Methods for Stem Packing for Rising Stem Steelvalves
SP-122-1997 Plastic Industrial Ball Valves
SP-123-1998 Non-FerrousThreaded and Solder-Joint Unions for Use With Copper WaterTube
(R-YEAR) Indicates year standard reaffirmed withoutsubstantive changes
A large number of former MSS Practices have been approvedby the ANSI or ANSI Standards, published by others. In order to maintain ? authoritative
information, the MSS withdraws its Standard Practices in such cases.
Manufacturers Standardization Society of the Valve and Fittings Industry, Inc.
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