Consult your Edward factory inside sales representative for
information on obtaining repair tools.
As always, field sales and service personnel are available
to assist with maintenance and repairs involving Edward
valves. And they are backed up by factory-trained specialists
to lend additional assistance whenever needed.
An improved low-maintenance Univalve design... tools for
fast in-line repairs...and reliable Edward service!
TABLE OF CONTENTS
Edward Customer Service ..............................................2
Three Tools for Faster In-line Repairs
of Edward Univalves ........................................................2
THREE TOOLS FOR FASTER IN-LINE REPAIRS OF
EDWARD UNIVALVES
Edward Univalves aren’t likely to require any maintenance
or repair work until they’ve been in services for quite a few
years. But sooner or later – depending on the nature of the
fluids, frequency of operation and time in service – Univalve
seats and disks may need to be repaired.
The Seat Refinishing Tool has
a self-centering head of multiple
tungsten carbide cutters on a
spindle which is hand-operated
with a speed wrench for complete
seat refinishing. Lapping or other
finishing work is not required to
produce refinished seats.
Seat damage, such as that
Seat Refinishing Tool
produced by foreign materials
in the line fluids, can be repaired
quickly.
The Bonnet Torquing Collar
is essentially a torque wrench
adapter that is used to remove
and reassemble the bonnet of an
unwelded Univalve.
The tool facilitates reassembly
of the bonnet with the required
torque correctly applied to ensure
that the graphitic body-bonnet
Bonnet Torquing Collar
gasket is properly loaded to
establish a leak-tight seal. The tool
may also be used to assemble and
disassemble seal-welded valves.
The Seal Weld Cutting Machine
has the ability to cut both fillet
and canopy welds. By removing
the handwheel and yoke, then
installing the machine, seal welds
can be cut, leaving a suitable weld
prep. The machine is operated by
one person and uses conventional
plant air.
*Class 4500 welded bonnet Univalves have a bonnet insert and graphic gasket seal ring, as shown on page 14.
3
DISASSEMBLING THE UNIVALVE
Line pressure must be relieved before disassembling
the valve.
1. Double-check to make sure that line pressure has been
relieved before disassembling the valve.
2. The valve should be in the open position and not
against the body seat or backseat.
EDWARD UNIVALVE USER INSTRUCTIONS ENGLISH 12-13
5. Loosen the yoke clamp bolt and nut. It is not necessary
to completely remove them.
6. Remove the yoke assembly by unscrewing it from
the bonnet. A gentle tap with a hammer might be
necessary before the yoke will unscrew away from
the bonnet. You may find it easier to remove the yoke
by placing the handwheel on the stem to prevent the
stem from rotating. When the yoke is even with the
top of the stem, and you can no longer use the valve
handwheel or handle, you will need to grasp the lower
portion of the stem between the yoke and bonnet. If
the yoke is turning freely, a cloth may be adequate to
hold the stem. If this is not adequate, a strap wrench
that will not damage the stem surface should be used.
If only the packing is to be replaced, this can now
be easily done with no further disassembly of the
Univalve. See Step 14.
3. If the valve is manually operated, remove the lock
nut that attaches the handwheel or impactor handle
to the valve stem. Remove the handwheel or handle.
If the valve is motor operated, remove the actuator
from the valve stem.
4. Loosen the two gland adjustment screws that rest
against the packing gland by threading them higher
into the yoke. A hex allen wrench inserted into the top
of the gland screw thru the holes in the top of the yoke
(remove the dirt protectors first) will speed this up.
7. If the yoke bushing is worn or damaged and must
be removed, insert 1⁄8” (or smaller) abrasive grinding
wheel into the slot on top of the bushing. Using a
standard grinding tool, work the grinder downward
to remove yoke metal that was upset into the bushing
during the valve assembly. Periodically during the
grinding process, try to turn the bushing within the
yoke to test how loose it is becoming. Once loosened,
use a screwdriver in the slot to turn the bushing. To
reinsert a new bushing, thread it into the yoke so that
the top of the bushing is flush with the top of the yoke.
Using a chisel and hammer, tap the yoke metal into the
bushing slot, creating an offset, so that the bushing is
tight within the yoke.
4
EDWARD UNIVALVE USER INSTRUCTIONS ENGLISH 12-13
DISASSEMBLING THE UNIVALVE
8. If the valve is unwelded, remove the locking collar.
9. If the valve to be repaired is seal-welded, prepare
the Seal Weld Cutting Machine for the weld cutting
operation. If a cutting machine is not available, use one
of the alternate methods shown on pg. 8.
(continued)
11. Remove the valve bonnet-stem-disk assembly if the
valve being repaired is a stop valve (figure XXX2X).
The disk in a stop-check vaIve (figure XXX6X) and
the bonnet insert in welded Class 4500 vaIves (figure
961XX) may be removed by forming a short piece of
soft wire into the shape of an L and lifting it up in the
disk bore.
10. Refer to the chart on pp. 10–13 to select the proper
torquing collar assembly (consisting of lock nut and
collar). Screw the torquing collar clockwise onto the
bonnet until it bottoms. A left hand threaded lock nut
is used to lock the torquing tool to the bonnet. Use
the appropriate size open end or socket/box wrench
(1-¼", 1-¾" or 2" hex) on the lock nut to turn the tool
counterclockwise to remove the bonnet.
12. Remove the stem from the bonnet. It may be necessary
to rotate the stem through the packing before it can be
removed.
13. If the valve is unwelded, the graphitic gasket must be
replaced. Do so by removing it from the valve body,
but take care not to damage machined surfaces.
14. Using a packing tool, remove the old packing.
Stainless steel Univalves are equipped with a
metal junk ring in the bottom of the packing
chamber. (See pg. 16 for repacking instructions.)
5
EDWARD UNIVALVE USER INSTRUCTIONS ENGLISH 12-13
SERVICING EDWARD UNIVALVE STOP AND STOP-CHECK VALVES
3. The Seat Refinishing Tool is now ready for operation.
Use a speed wrench to operate the tool. Because this
manual process is fast, a special air or electric motor
should not be used. The tool assembly can be easily
Line pressure must be relieved before making any
repairs.
If seat damage has occurred, outlined below are step-bystep procedures for fast, in-line repairs using the Edward
Seat Refinishing Tool.
1.
See pp. 4–5 for proper disassembly procedures before
performing repairs on the Univalves. Then, using the
charts on pp. 10–13, select the proper Seat Refinishing
Tool Arrangement for performing repairs on the seat area.
removed to inspect the seat and determine if more seat
refinishing is required. Turn the tool clockwise using
light pressure only on the stellite seat.
Univalves can be reseated several times, assuming
nominal amounts of stellite are removed each
time. A typical resealing operation removes several
thousandths of an inch of stellite; severe seat defects,
of course, would remove more. A total of about
.03 inch of stellite can be removed before the stellite
becomes too thin, or approximately five average
refinishing operations.
2. Take appropriate caution to make sure the inlet and
outlet valve ports are blocked to prevent removed seat
material from entering the line. Then, screw the Seat
Refinishing Tool Assembly into the body while holding
the shaft up to prevent tool and seat contact. The guide
needs only to be hand-tightened. Do not damage the
cutters by dropping the tool on the stellite seat.
4. When a repair of the seat is finished, use a portable
vacuum to remove loose chips.
6
SERVICING EDWARD UNIVALVE CHECK VALVES
Line pressure must be relieved before servicing
the valve.
1. If the check valve to be repaired is seal-welded,
prepare the Seal Cutting Machine for the weld-cutting
operation. If a cutting machine is not available, use one
of the alternate methods on pg. 8.
EDWARD UNIVALVE USER INSTRUCTIONS ENGLISH 12-13
3. Remove the check valve spring and disk from the body
bore. A short piece of soft wire formed into an L shape
may be used to assist in disk removal by engaging it in
the groove inside the disk.
2. Once a seal-welded valve has been cut, it is ready for
disassembly. Unscrew vaIve cover from the body using
the flats provided.
4. The check valve is now ready for internal work.
See the section entitled “Servicing Edward Univalve
Stop and Stop-Check Valves” (pg. 6) for correct repair
procedures.
7
EDWARD UNIVALVE USER INSTRUCTIONS ENGLISH 12-13
ALTERNATE WELD-CUTTING METHODS FOR UNIVALVES
SCARFING A WELD
(For fillet-welded Univalves) carbon steel and low alloy
valves
Line pressure must be relieved before making any
repairs.
GRINDING A WELD
(For canopy seal Univalves) stainless steel valves
Open valve to backseat. Using a standard grinding wheel,
remove the weld by grinding from the top of the body face
and bonnet outside diameter (see photo). Continue this
process around the valve until all weld is removed where
the body and bonnet are joined together. Clean the valve
with a wire brush. A penetrating oil may be used where
permissible to loosen the threads joining the body and
bonnet.
1.Air-arc method Open valve to backseat.
Using air-arc equipment, make a series of cuts in the
valve weld (see photo and sketch). Continue making
cuts until the valve weld takes on a grooved scarfedout appearance. Clean the valve with a wire brush.
A penetrating oil may be used where permissible to
loosen the threads joining the body and bonnet.
2.Oxyacetylene method Open valve to backseat. Using
an oxyacetylene torch equipped with a scarfing tip,
make a series of cuts in the weld until it takes on a
scarfed-out, grooved appearance. Clean the valve with
a wire brush. A penetrating oil may be used where
permissible to loosen threads joining the body and
bonnet.
This sketch shows the sequence of cuts necessary to remove the fillet weld by both
oxyacetylene and air-arc methods. Place scarfing torch or welding electrode tangent
to the bonnet, as indicated in position A. When metal reaches cutting temperature,
start blowing oxygen or air while moving torch backward. Weld metal should be
blown away. Move torch counterclockwise to position B. Repeat until entire fillet
weld is removed and gap is continuous. DO NOT REMOVE EXCESS MATERIAL
A
FROM BONNET OR UPPER BODY FACE.
B
8
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