Flowserve Edward Cast Steel Bolted Bonnet Valves User Manual
Maintenance Manual for Edward
Edward Valves
Maintenance Manual for Edward
Cast Steel Bolted Bonnet Valves
V-380 R2
2
Flow Control Division
Edward Valves
Table of Contents
Page
KEY TO ILLUSTRATIONS.......................2
INTRODUCTION TO THIS MANUAL ......3
BOLTED BONNET VALVE
FIGURE NUMBERS...............................3
SERVICE PROBLEMS
Packing Chamber leak .....................3
Packing Recommendations................3
Bonnet Gasket Leak, Bolting Torques ..4
Seat and Disk Joint Leak...................5
Body Wall Leak ...............................5
Objectionable Vibration, Noise or
Excessive Pressure Drop....................6
Valve Lubrication..............................6
REPAIR PROCEDURES
Valve Body Repairs
Body Bore Guide Rib Repair .............7
Seat and Disk Repairs ......................7
Body Wall Repairs...........................8
Valve Component Repair
Disk-Piston Assembly Repairs.............9
Gasket Seal Area Repair ..................9
Welding Rod Recommendations.........9
Field Repair Equipment...................10
DISASSEMBLY PROCEDURES FOR
BOLTED BONNET VALVES
Introduction...................................11
First Determine the Area of Failure...11
Page
DISASSEMBLY PROCEDURES FOR
IMPACTOR HANDWHEELS.................11
PROCEDURE FOR REMOVING ELECTRIC
ACTUATORS FROM VALVE BONNETS
Revolving Stem Valves ....................12
Non-Revolving Stem Valves .............12
Electric Operator Limit Switch and
Torque Switch Setting Procedures.....13
Geared Limit Switch.......................13
Torque Switch ................................13
DISASSEMBLY PROCEDURES
FOR VALVE PARTS
Stop and Stop-Check
(Non-Return) Valves........................14
Piston Lift Check Valves...................14
REASSEMBLY PROCEDURES FOR
BOLTED BONNET VALVES
Introduction...................................15
Stop and Stop-Check
(Non-Return) Valves........................15
Piston Lift Check Valves...................15
SUPPLEMENTARY REPAIR
INFORMATION.................................15
INFORMATION REQUEST ..................12
ORDERING PARTS.............................16
KEY TO ILLUSTRATIONS
Ill. No. Title Page
No. 1 Typical Valve Nomenclature.....5
No. 2 Lapping Equipment...............10
No. 3 Impactor Handwheel
with Crossarm......................12
No. 4 Impactor Handwheel with
Adapter...............................12
No. 5 Electric Operator on
Revolving Stem Valve............13
No. 6 Electric Operator on
Non-Revolving Stem Valve .....13
No. 7 Piston Lift Check Valve...........14
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Flow Control Division
Edward Valves
Introduction and Service Problems
Introduction
Cast Steel Bolted Bonnet
This manual has been prepared to serve as
a guide for the maintenance of Edward
bolted bonnet valve construction. It is
designed to help you in obtaining the most
satisfactory ser vice from these valves.
Although rigid metallurgical, radiographic,
physical and visual inspection is the standard procedure for all Edward products, it
is inevitable that some valves, after a
period of time, may occasionally require
repair. When this happens, this manual
will assist you so that your valve may be
satisfactorily restored to good working
condition with a minimum of time and
expense.
Before starting, it will be helpful to have
some understanding of the valve’s physical
construction. The drawing on pg. 5 will
give you some idea of how the valve is put
together.
The next major section of this manual discusses the more common service problems
and failures. It identifies the problem and
explains the reasons for certain failures.
The reason should be understood before
work is actually started.
Then the procedure to be followed in making the repair is explained. This includes
normal valve maintenance as well as major
valve repair. Field repair equipment, available from Edward Valves, is described and
illustrated. Valve lubrication and welding
rod recommendations are also made. These
procedures are adequate for almost any
valve repair or maintenance problem that
may arise in the field.
The next major section describes the disassembly procedures for the various valve
components.
It is very impor tant that the Introduction
and the paragraphs titled “First Determine
the Area of Failure” be read and understood before any disassembly work is
begun. Several procedures are described,
depending upon the area of failure.
Considerable time can often be saved by
first selecting the proper disassembly
procedures.
The last major section explains how the
various valve constructions are to be
reassembled. Information on how to
contact Edward Valves for additional
advice, if required, and how to order
parts is included.
FIGURE NUMBER OF EDWARD
BOLTED BONNET VALVES
DESCRIBED IN THIS MANUAL
302 329Y 605Y 1324
302Y 390 618 1324Y
303 390Y 618Y 1390
303Y 391 619 1390Y
304 391Y 619Y 1392
304Y 392 670Y 1392Y
318 392Y 690 1441
318Y 393 690Y 1441Y
319 393Y 691 1443
319Y 394 691Y 1443Y
328 394Y 1302 1641
328Y 604 1302Y 1641Y
329 604Y 1314 1643
605 1314Y 1643Y
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
packing sets. This is a combination of
packing using braided rings at the top and
bottom of the packing chamber and flexible graphite packing in the center section.
Packing glands should be tightened down
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Flow Control Division
Edward Valves
Service Problems (cont.)
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 in 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 A 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.
BONNET GASKET LEAK
A torque wrench should be used for tightening the bonnet or cover retainer studs or
cap screws which are used to preload the
soft iron gasket.
The following procedure is recommended:
1. Guard against leakage by having these
bolts tight at all times.
2. With line pressure in the valve, all nuts
or cap screws should be tightened to
the torque shown below.
Should the leak fail to stop after tightening,
it must be concluded that there is an imperfect seal, and the valve will have to be
opened for examination. Such a leak may
result from either of the following causes:
1. Incomplete Seal Between Bonnet and
Gasket or Body and Gasket. An incom-
plete seal around the gasket seating surfaces may be caused by corrosion, dirt,
chips, or other foreign matter on the
mating surfaces. An incomplete seal
may be caused by surface imperfections
in the body or bonnet surfaces 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 of deeper flaws in the body
casting which may cause a by-pass
around the gasket.
INITIAL FINAL
FIGURE NUMBERS SIZE TORQUE TORQUE
328, 328Y,
329, 329Y, 2.5 24 6
1441, 1441Y,
1443, 1443Y
302, 302Y 2.5 24 6
303, 303Y 3 27 6
304, 304Y 4 27 6
318, 318Y 5 41 9
319, 319Y 6 55 13
860 14
10 89 21
12 143 33
1302, 1302Y 6 40 9
1314, 1314Y 8 68 16
1324, 1324Y 10 76 18
12 140 32
1641, 1641Y 2.5 24 7
1643, 1643Y
604, 604Y 2.5 27 8
605, 605Y 3 27 8
618, 618Y 4 41 12
619, 619Y 5 55 16
660 17
TABLE A
GLAND BOLT TORQUES, FT-LBS
Bolt diameter, Inches 1/2 9/16 5/8 3/4 7/8 1 1-1/8 1-1/4
Torque, Ft. Lbs. 45 68 90 150 240 370 585 750
2. Leakage at the Gasket. The possibility of
a leak through the gasket itself, while
remote, should still be considered. This
may not be the result of external flaws
on the sealing surfaces of the gasket.
SEAT AND DISK JOINT LEAK
A leak existing between the seat and disk
of a 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 water
or steam lines, a downstream pipe that
remains hot beyond the usual length of
time and conductivity range.
Such a leak may be the result of a distorted seat caused by uneven welding and
stress relieving temperatures that were present in the body when mounting the valve
in the pipe line. It may also develop
because of the operator’s failure to close
the valve tightly. An increased velocity is
imparted to a flow forced through a very
small opening. This increased velocity subsequently gives rise to the “cutting” of both
disk and seat, particularly by particles of
line scale or rust in suspension or normal
solids in solution; or, in spite of the fact
that the hard surfaced material on the seat
and disk is corrosion and erosion resistant,
grooves, pit marks, or other surface irregularities may be formed on the seat and
disk joint surfaces when the disk is closed
against a foreign body on the seat. This
sometimes occurs during the initial start up
of a piping system.
Leakage of steam through a valve which is
badly steam cut has a whistling or
sonorous sound. If the valve is only slightly
steam cut, however, leakage is identified
by subdued gurgling or weakly popping
sounds. These sounds can be heard
through a stethoscope or by placing one
end of a stick against the valve body while
holding the other end between the teeth,
with hands over the ears.
BODY WALL LEAK
This is a visual leak through the body wall,
welding end or end flanges and may be
the result of a shrink cavity or other void in
the casting. If small at first, such a leak
may go unnoticed for a time, particularly if
the valve is heavily insulated and the pipe
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Flow Control Division
Edward Valves
Service Problems (cont.)
6
Flow Control Division
Edward Valves
Service Problems (cont.)
line at that point is sufficiently warm to
keep the insulation dry enough to escape
notice.
OBJECTIONABLE VIBRATION NOISE
OR EXCESSIVE PRESSURE DROP
Excessive vibration noise or humming coming from within a stop-check (non-return) or
check valve indicates the possibility that
the disk-piston assembly is wedged inside
the body. Such sticking may be caused by
uneven body guide rib wear on the downstream side induced by oversizing the
valve, by corrosion, by flakes of line scale,
or by particles of weld spatter that may
have entered the valve during construction
of the piping, and which later washed up
into the piston bearing area of the
body I.D.
The stem of a stop-check valve should
normally be fully open in order that the
disk-piston can lift the full amount. When
the disk is not touching the bottom of the
stem or the bottom stop lugs on the bonnet
(due to a wedged disk piston or insufficient
flow, for example), then the disk assembly
is free to move laterally within the body.
This motion in most cases causes a slight
vibration which can be felt through the
body, bonnet and handwheel. Screwing
the stem down slowly to contact the disk
first increases the intensity of vibration to
the hand and to the ear, but further downward movement of the stem builds up sufficient contact pressure and eliminates the
vibration. This also tends to dislodge any
foreign particles which may have been the
initial cause for disk-piston wedging.
The position of the stem where vibration
ceased, should be noted and any increase
in pressure drop indicated on available
gages, recorded. It may be that when the
stem is screwed back to the full open position, the disk will again remain in a floating position which could indicate oversizing of the valve for the flow conditions. It is
always recommended that check valve size
selection be governed by flow conditions
rather than by adjacent piping. Oversizing
induces vibration or noise and causes
excessive, uneven guide rib wear giving
rise to greater disk-piston assembly clearance on one side of the body.
Another way to dislodge a wedged piston
is to use other valves in the line. If possible, vary the rate of flow through a noisy
check valve sharply enough (in a short
period of time) to dislodge the piston from
its wedged position.
LUBRICATION
In order to obtain full service life, valves
require periodic lubrication of the bearings
and stem threads, as does any rotating
machinery.
On valves where the stem bushing and
bearings are in the motor actuator, the
bearings are lubricated by the actuator
lube supply, which should by maintained
at the recommended level.
Stem threads also require periodic replenishment of the lubricant. Exposed threads
should be wiped clean of old grease and
accumulated dirt and fresh lubricant
applied. This is most effectively done with
the valve in the closed position.
For valves that see frequent operation, the
lubricant should be replenished on bearings and stem threads every three months.
If extreme service conditions dictate, the
plant operating engineer should establish a
more frequent re-lube schedule.
For valves that are operated infrequently,
relubrication at least once a year is recommended. The recommended lubricant for
stem threads is Rykon EP #2, manufactured
by The American Oil Company. This is an
extreme pressure, extreme temperature
lubricant of high quality.
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