Flowserve V-378 User Manual
Edward Valves
Maintenance Manual for Edward
Equiwedge
™
Gate Valves
V-378 R1
2
Flow Control Division
Edward Valves
Table of Contents
Introduction and Scope .........................3
Gate Valve Figure Numbers ...................3
Description of Equiwedge
Gate Valve Types...............................4
Type I..................................................4
Type II..............................................4-5
Type III................................................5
Type IV................................................5
Type V.................................................5
Service Problems ..................................6
Packing Chamber Leak.......................6
Packing Recommendations..................6
Pressure Seal Gasket Leak ..................7
Pressure Seal Leak.............................7
Gate and Seat Leakage......................8
Body or Bonnet Wall Leak ..................8
Lubrication........................................8
Repair Procedures.................................9
Valve Body Repairs.– Body
Bore Gasket Seal Area Repairs.........9
Body Wall Repairs...........................10
Body Guide Repairs.........................10
Seat Repairs....................................10
Gate Repairs ...................................11
Bonnet Repairs ................................11
Backseat.........................................11
Porosity in Bonnet............................12
Stem Repairs...................................12
Field Repair Equipment.....................12
Disassembly Procedure for
Equiwedge Gate Valves....................13
Disassembly Procedure for Bonnet Types,
Area 3
Type I .............................................14
Type II............................................15
Type III ...........................................16
Type IV & V ....................................17
Reassembly Procedures for Equiwedge
Gate Valves ....................................18
Exploded View...................................19
Reassembly Instructions........................20
Handwheel Actuated Valves ..............20
Tapered Roller Bearing
Preload Instructions ........................21
Reassembly Instructions for
Valves with Composite Pressure
Seal Gaskets Only.........................23
Type I Reassembly............................24
Type II Reassembly...........................25
Type III Reassembly ..........................26
Type IV & V Reassembly...................26
Appendix A
Procedure for Removing Manual
& Electric Actuators...................28-29
Appendix B
Valve Tools Available for Rental.........30
Terms and Conditions ..........................31
Contact Information ............................32
TABLES
Table 1 Gland Bolt Torques.................7
Table 2 Bonnet/Cover Bolt/
Nut Pull-up Torques.................7
Table 3 Welding Rod
Recommendations ................22
Table 4 Dimensions for
Bearing Preload Washer.......22
Table 5 Bearing Retainer
Preload Torque ....................22
Table 5A ..........................................22
Table 6 Bearing Retainer
Final Torque ........................22
Table 6A ..........................................22
Table 7 Composite Gasket
Bonnet/Cover Bolt/Nut
Pull-Up Torques ....................23
3
Flow Control Division
Edward Valves
Introduction and Scope
Introduction
This manual has been prepared to serve as
a guide for maintenance of Edward
Equiwedge gate valves, all of which
feature the pressure seal bonnet joint
construction. Although rigid metallurgical,
non-destructive examination, physical and
visual inspection is standard procedure for
Edward Valves products, it is inevitable
that some valves, after a period of time,
will require repairs. This manual will assist
you in restoring the valve to good working
condition with a minimum of time and
expense.
Scope
Before starting any repairs, it will be
helpful to have some understanding of the
valve’s physical construction. Consequently,
the five basic types of pressure seal construction are discussed and illustrated first.
All Equiwedge gate valves employ one of
these five basic types.
The next major section of this manual
discusses the more common service
problems, and explains the reason for
certain failures. The reason for the problem
should be understood before work is actually started.
Then, the procedure to be followed in making the repair is explained. This section
includes normal valve maintenance as well
as major valve repairs. Field repair equipment available from Edward Valves is
described and illustrated. Valve lubrication
and welding rod recommendations are
also included. These procedures should be
adequate for almost any Equiwedge gate
valve repair or maintenance problem that
may arise.
Following is a section describing the
disassembly procedure for the various
valve components; for example, manual
handwheel, manual geared actuators or
electric actuators, valve yokes, and the five
basic bonnet types. It is very important that
this manual be studied before any
disassembly work is done to avoid needless work and loss of time by selecting the
improper procedures.
The last sections include reassembly instructions and available maintenance equipment and information on the various types
of actuators, both manual and electrical.
Figure No. Class Pressure Seal Type Size
1611-1611Y 600 I & II 21⁄
2 to 28
1711Y Special Class 600 I & II 21⁄2 to 28
1911-1911Y 900 III, IV, & V 21⁄
2 to 28
14311Y Special Class 900 III, IV, & V 21⁄
2 to 28
11511-11511Y 1500 III, IV, & V 21⁄2 to 24
12011Y Special Class 1500 III, IV, & V 21⁄2 to 24
12511-12511Y 2500 III, IV, & V 21⁄2 to 24
14411Y Special Class 2500 III, IV, & V 21⁄2 to 24
Gate Valve Figure Numbers Described in this Manual
4
Flow Control Division
Edward Valves
Description of Equiwedge Gate Valve Types
Type I is a flanged yoke design with a
separate gasket retainer ring, both of
which are held to the body by cap
screws. The bonnet retainer is screwed
onto the bonnet and cap screws are
screwed down on top of the body to force
the bonnet into contact with the gasket.
See illustration No. 1.
Type II is a flanged yoke design with or
without a separate bonnet retainer ring,
both of which are held on the body by
cap screws or studs and nuts. The bonnet
is pulled up into contact with the gasket
with studs and hex nuts. See illustrations
Nos. 2A and 2B, pgs. 4 and 5.
Type III is a wishbone yoke design bolted
to the body. It has a segmental retaining
ring, spacer ring and a screwed on
bonnet retainer equipped with push down
bolts to pull the bonnet up into contact
with the gasket. See illustration No. 3,
pg. 5.
Type IV is a wishbone yoke designed bolted to the body. It has a segmental
retaining ring, spacer ring and separate
bonnet retainer with pull up studs screwed
into the bonnet to contact the gasket. See
illustration No.4, pg. 5.
Type V has a yoke lock ring connection to
the body with a segmented ring, gasket
retainer and a separate bonnet retainer
with studs screwed into the bonnet to pull
up the bonnet against the gasket. See
illustration No. 5, pg. 5.
Illustration No. 1 Illustration No. 2A
Size 2-1/2 & 3 - Figure 1611 and 1611Y Size 4” -Figure 1611 and 1611Y
Size 2-1/2 & 3 - Figure 1711Y Size 4” - Figure 1711Y
Valve Type I Valve Type IIA
5
Flow Control Division
Edward Valves
Description of Equiwedge Gate Valve Types (cont.)
Illustration No. 2B
Size 6 - 28 - Figure 1611 and 1611Y
Size 6 - 28 - Figure 1711Y
NOTE: Size 6 and 8 valves are wishbone yoke design with flange.
Valve Type IIB
Illustration No. 4
Size 4 - 8 - Figure 1911-1911Y-14311Y
Size 4 - 8 - Figure 11511-11511Y-12011Y
Size 4 - 8 - Figure 12511-12511Y-14411Y
Valve Type IV
Illustration No. 3
Size 2-1/2 - 3 - Figure 1911-1911Y-14311Y
Size 2-1/2 - 3 - Figure 11511-11511Y-12011Y
Size 2-1/2 - 3 - Figure 12511-12511Y-14411Y
Valve Type III
Illustration No. 5
Size 10 - 28 - Figure 1911-1911Y-14311Y
Size 10 - 24 - Figure 11511-11511Y-12011Y
Size 10 - 24 - Figure 12511-12511Y-14411Y
Valve Type V
6
Flow Control Division
Edward Valves
Service Problems
Packing Chamber Leak
Where moisture appears or actual dripping
occurs at the packing chamber around the
stem, gland or gland flange which cannot
be eliminated by re-torquing the gland bolt
the following points should be considered.
1. The packing may have become hard.
Replace the packing.
2. Gland travel has been fully taken up.
Repack with new packing.
3. The wrong packing is being used.
See packing recommendations shown
on this page.
4. A stem should be replaced when it
has become deeply scratched,
burred, or otherwise mutilated from
careless handling, or where the stem
has worn, tapered or has been bent.
5. The gaps in the rings of split packing
have not been staggered around the
stem. They should be inserted in this
manner.
6. The packing gland may be binding
against the packing chamber or stem
and does not compress the packing
properly. Make certain the gland fits
the packing chamber and is tightened down equally on each side.
Packing Recommendations
Edward valves are packed with all-purpose
with packing sets. This is a combination of
packing using braided rings at the top and
bottom in the packing chamber and flexible graphite packing in the center section.
Packing gland should be tightened down
enough to prevent leakage but not enough
to develop excessive operating torque.
When the gland has advanced approximately half way into the packing chamber,
it is recommended that additional packing
rings be added. To obtain best results,
the stem should be thoroughly cleaned.
Replacement packing should be the same
as that originally furnished.
We recommend that replacement packing
be purchased from Edward Valves to
assure packing with the proper density and
corrosion inhibitors is always used.
IMPORTANT:
Long service life from modern graphitic
packing requires that adequate preloads
be applied when repacking.
1. All parts should be clean and not
scored or pitted, especially the stem.
2. The valve internal parts and bonnet
should be assembled prior to
installing the packing.
3. Position split packing rings with the
ends of adjacent rings rotated 90°.
4. Install in the following sequence:
Bottom Ring – Braided Ring
Center Rings – Die formed
expanded graphite
Top Ring – Braided Ring
5. Clean and lubricate the gland eyebolts.
6. Carefully seat each individual packing ring before adding the next ring.
7. Apply the recommended torque to
the gland nuts evenly without cocking
the gland. See Table 1, pg. 7, for
recommended torques.
8. Tighten the nuts to the initial values
shown, then loosen and re-tighten to
the final torque.
9. Stroke the valve, then re-check the
gland nut torques.
Note: The torque values given are for
sealing full rated pressure. For line pressures less than the full CWP rating of the
valve, the final torques may be reduced by
the ratio of P
actual
/CWP down to a mini-
mum of P
actual
= 1500 psig. This will
reduce packing drag and extend packing
life.
Flow Control Division
Edward Valves
Service Problems (cont.)
Pressure Seal Gasket Leak
Edward valves have been produced with
two types of pressure seal gasket: Earlier
valves had metal gaskets, while later
designs have composite expanded graphite
gaskets. The valves with composite gaskets
can be identified by a “B” prefix on the figure number. Assembly and disassembly of
the two gasket types are essentially the
same except the composite gasket designs
have belleville spring washers under the
nuts (or capscrews) of the pull-up bolting,
and the tightening torque requirements for
the pull-up bolting are different.
To guard against leakage, the bolts should
he kept tightened at all times.
A torque wrench should be used for tightening the bonnet or cover retainer stud nuts or
capscrews which are used to pre-load the
pressure seal gasket.
All nuts/capscrews should be tightened in
an alternating star pattern to insure even
tightening.
The bolting should be tightened to the
torque values shown in Table 2 while the
valve is under full line pressure.
Pressure Seal Leak
Should the leak fail to stop after tightening,
it must be concluded that there is an imperfect pressure seal, and the valve will have
to be opened for examination.
(Note: Regardless of the cause of failure,
opened pressure-seal bonnets should
always be reassembled with a new gasket.
These are available from stock via Air
Express from Raleigh, North Carolina.)
Such a leak may result from any of the
following causes:
1. Incomplete Seal Between Bonnet and
Gasket. An incomplete seal around
the gasket seating surface of the bonnet (or cover on check valves) may be
caused by corrosion, dirt, chips, or
other foreign matter on the mating surfaces of the sealing angle.
2. Incomplete Seal Between Body I.D.
and Gasket. An incomplete seal in the
INITIAL FINAL
FIGURE NUMBERS SIZE TORQUE TORQUE
2.5 26 8
326 8
426 8
629 8
844 13
1611, 1611Y, 1711Y 10 67 19
12 72 21
14 76 22
16 95 27
18 121 35
20 127 37
24 156 45
28 221 64
2.5 26 11
326 11
426 11
644 19
864 28
1911, 1911Y, 14311Y 10 72 31
12 107 46
14 151 65
16 159 69
18 167 72
20 208 90
24 193 84
2.5 26 19
326 11
429 21
648 35
890 65
11511, 11511Y, 12011Y 10 151 109
12 223 161
14 242 175
16 343 247
18 353 255
20 378 273
24 268 193
2.5 26 26
326 26
429 29
6 101 101
8 133 133
10 155 155
12511, 12511Y, 14411Y 12 311 311
14 199 199
16 442 442
18 311 311
20 503 503
22 663 663
24 806 806
TABLE 1
GLAND BOLT TORQUES, FT-LBS
CLASS 300 & 600 VALVES
TABLE 2
BONNET/COVER BOLT/NUT PULL-UP
TORQUES
(WITH VALVE UNDER PRESSURE)
REQUIRED TORQUE, FT-LBS
BOLT SIZE METAL COMPOSITE
GASKET GASKET
3/8 18 5
7/16 30 5
1/2 45 7
9/16 68 10
5/8 90 15
3/4 150 25
7/8 240 35
1 370 55
1 1/8 533 80
1 1/4 750 110
1 3/8 1020 150
1 1/2 1200 170
1 5/8 1650 230
1 3/4 2250 320
1 7/8 3000 420
2 3300 460
7
8
Flow Control Division
Edward Valves
Service Problems (cont.)
area of the gasket and body I.D. contact
may be caused by surface imperfections
in the body wall in the form of pin holes,
extended cracks, or indentations where
the metal has failed sometime after valve
installation and use. Such imperfections
may be surface indications deeper flaws
in the body casting which may cause a
by-pass around the pressure seal.
Gate and Seat Leakage
A leak existing at the seat and gate of a
properly closed valve might be indicated
by one of the following: a definite pressure
loss in the high pressure side of the valve;
continued flow through an inspection drain
on the low pressure side; or, in hot lines, a
downstream pipe that remains hot beyond
the usual length of time and conductivity
range. First, try opening the valve slightly
to flush any foreign material from the seating surfaces and then fully close the valve.
If this doesn’t stop the leakage, then one or
more of the following may be the cause:
1. Foreign material has been imbedded
into the seating surfaces preventing a
seal.
2. Foreign material has scratched or cut
the seating surface.
3. An obstruction such as a tool or other
foreign material has been lodged across
or between the seats and preventing the
gate from closing.
4. The valve seat has been steam or water
cut by not fully closing the valve during
a previous operation.
If the valve cannot be isolated and
repaired as soon as possible, schedule the
work to be done at the next outage.
Body or Bonnet Wall Leak
This is a leak through the pressure containing parts of the valve. A leak occurring
through the bonnet should be readily
detectable because of the lack of insulation. On the body, because of the heavy
insulation, a small leak may go unnoticed
for a time on a hot line because the piping
evaporates the leakage.
Lubrication
In order to obtain long service life and
maximum reliability, valves require periodic lubrication of the bearings and stem
threads the same as for any machinery
with rotating parts.
All handwheel actuated Equiwedge gate
valves are equipped with low friction bearings, needle bearings in the smaller sizes
and tapered roller bearings in the larger
sizes. These valves have a lube fitting for
convenient relubrication. Both the stem
threads and the bearings can be relubed
through this fitting. In addition, it is advisable to clean the stem first while in the
open position and apply fresh grease to
the threads, then repeat while in the closed
position.
For valves that are operated infrequently,
relubrication at least once a year is recommended. The recommended lubricant for
both bearings and stem threads is Rycon
EP 2, manufactured by the American Oil
Company. This is an extreme pressure,
temperature lubricant of high quality. Use
of other lubricants should be avoided.
For valves that are operated frequently, the
lubricant should be replenished at both the
bearings and stem threads every three
months or at shorter intervals depending
on the severity of the service.
9
Flow Control Division
Edward Valves
VALVE BODY REPAIRS
Body Bore Gasket Seal Area Repair
(Valves with metal gasket only)
Class 600 Equiwedge gate valves have
the seal area for the pressure seal just
below the top of the body bore. The seal
surface is inlaid with 18-8 stainless steel
on all valves size 16 and larger.
Class 900 and higher Equiwedge gate
valves have the seal area just below the
gasket retainer groove. The seal surface is
inlaid with 18-8 stainless steel on all valves
in these pressure classes.
The seal area, whether inlaid or not, must
be smooth, round and without any appreciable taper. Upon normal disassembly of
the valve the gasket may leave some vertical score marks when withdrawn.
If the depth of defects are .010” or less,
the seal area can be honed using a
portable Sunnen Hone. This device is
adjustable for different bore sizes and can
be operated by one man using a portable
electric drill of 1/2” to 3/4” capacity.
When the defects are greater than .010”,
welding will be required to cut down the
repair time.
First make visual inspection all around this
area, noting, if possible, where flaws may
occur. Next wash the area with a suitable
solvent, drying with clean rags and, if necessary, polishing with a fine grade of
emery cloth to remove any undesirable
scale or foreign matter which may be been
deposited on the area suspected of having
flaws. Use a dye penetrant test if cracks
are suspected.
Where it is necessary to repair the body
inlay by welding, note the following:
1. Prior to any cutting or welding oper-
ations being performed on the valve,
it is necessary that adequate seat
joint protection be provided and
some means of insurance against
getting chips, weld spatter or other
foreign matter into the pipe line if
the valve is permanently mounted. A
round piece of sheet metal placed in
the bore down to the shoulder above
the guide grooves and taped in
place will protect the guide surfaces
and seats.
2. Chip out the defective area in the
body, being careful to remove the
affected portion to its end, inside the
casting, and to thoroughly clean it
away.
3. With a small hand grinder, grind the
chipped area smooth.
4. Preheat an area large enough
around the imperfection so that during the entire welding operation heat
will be retained at approximately
400 degrees Fahrenheit.
5. Use a stainless steel inlay selected
from either 18-8 stainless steel rod,
Harstain 18-8, Stainweld “K” 18-3,
Stainweld 18-8 or equivalent.
6. Lay the weld in thin, even layers,
peening each layer before proceeding with the next, and being careful
to maintain a temperature above
400 degrees Fahrenheit in the area
being repaired. Peening the bead
actually stretches it and counteracts
its tendency to contract and shrink as
it cools. The last layer of weld must
overlap onto the sound metal to
insure a weld without an undercut at
the edges. The overlapping should
be done along this edge by using a
welding rod of 1/8” maximum diameter. The last layer should bring the
height of the welded area up to
1/16” above the original surface, as
checked with a straight edge along
the body bore.
For this type of weld repair, it is recommended that the last layer be
pounded while still hot with the flat
face of the hammer. Thermal stress
relieving is not recommended.
With a hand grinder, rough grind
the welded surface to within about
.010” of the finished surface. A simple template cut from thin sheet
metal and having the same arc as
the body bore diameter, and straight
edge laid along the body bore can
be used as a guide. A final cut then
can be made, using a fixture similar
to the one shown in Illustration No.
9, pg. 15. Final finishing can be
done with the adjustable Sunnen
hone described on this page.
After removing all the dirt, chips,
slag, spatter, and grinding dust from
the body, the bore should be polished with fine emery cloth and then
thoroughly cleaned before reassembly of the valve.
Repair Procedures
10
Flow Control Division
Edward Valves
It is best that a new pressure-seal
gasket be used upon reassembly.
Body Wall Repairs
There are five basic steps in repairing a
casting defect:
1. Cut out to sound metal. Attempting to
weld over the defect will only leave a
notch that may re-introduce the defect.
Cutting may be done by chipping,
grinding or flame gouging. The amount
of metal removed should be held to a
minimum to avoid distortion during subsequent welding.
2. Preheat, using the minimum temperature
specified by the material specification
and/or the design code. Use at least
400F on WC9 or C5 material, 300F
on WC6. Although cast carbon steels
such as WCB or WCC do not require
preheat, it may be advantageous to
remove any moisture or other contaminants from the area to be welded. This
may also identify any leak paths. There
are also disadvantages to preheat,
especially localized preheat, that must
be considered when working in areas
of the casting with finish machined
dimensions. Distortion may result in
more damaging problems than those
concerns created by the original defect.
Lower preheats and the control of interpass temperature are two methods used
to minimize distortion.
3. Welding should be done by qualified
welders, using qualified procedures and
weld material of a chemistry matching
the casting (see Table 3 for welding rod
recommendations). The final weld
TABLE 3 – WELDING ROD RECOMMENDATIONS
MATERIAL TO BE WELDED
WELD ROD
RECOMMENDATIONS
ASME IX
Material ASTM Grade AWS Classification
P-Numbers
P-1 Carbon Steel 1. ASTM A216, Grade WCB AWS 5.1
2. ASTM A105 E7018
P-4 1-1/4% Chromium, 1. ASTM A217, Grade WC6 AWS 5.5
1/2% Molybdenum 2. ASTM A182, Grade F11 E8018-B2
Low Alloy Steel
P-5 2-1/4 Chromium, 1. ASTM A217, Grade WC9 AWS 5.5
1% Molybdenum 2. ASTM A182, Grade F22 E9018-B3
Low-Alloy Steel
P-8 18% Chromium, 1. ASTM A351, Grade CF8M AWS 5.4
8% Nickel 2. ASTM A182, Grade F316 E316
Stainless Steel
P-8 18% Chromium, 1. ASTM A351, Grade CF8C AWS 5.4
8% Nickel 2. ASTM A182, Grade F347 E347
Stainless Steel
Repair Procedures (cont.)
WELDING EDWARD VALVES IN-LINE
When welding a valve in line, the installer
should apply the specific technical rules
imposed by the jurisdictional authority of the
area where the valve is installed, In the
absence of such rules, following are
suggested practices for welding Edward
Valves in line:
1. Welding should be done using procedures
and personnel qualified in accordance
with ASME Section IX. Rules for preheat
and postheat are stated in Chapter V of
ASME B31.1 (Power Piping).
2. The valve should be welded in line, one
end at a time, in a closed position
(approximately a half-turn after the seat in
the body comes in contact with the disk).
This is suggested to preclude warpage
between seating surfaces caused by temperature induced stresses during welding
or subsequent heat treat. It also protects
the seat from weld spatter that might coat
the lapped seat and disk. When postweld
heat treat is required, each weld end
should be heat treated one at a time, to
minimize impact of heat on valve internals.
Do not heat treat an Edward Valve with a
piping attached as a unit in a furnace, as
warpage of parts may occur. After welding, open the valve and flush the line to
clean out all foreign matter.
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