3
Ensure all necessary replacement parts are on hand
before commencing service. Disassemble only as far
as needed to inspect/replace worn parts.
1. Ensure there is no pressure within the valve
and operating equipment is locked out.
2. Loosen a fitting and drain the oil from the
reservoir into a clean container for re-use
after re-assembly. Note position of closing
speed control valve. Remove the tubing
between the valve cover and reservoir.
Remove the reservoir mounting bolts (24A)
and the reservoir (24).
3. Mark the position of the adjusting stem (26)
or measure its height above the top of the
spring chamber (22).
4. Loosen the adjusting stem lock nut (25) and
turn the adjusting stem counterclockwise to
de-compress the spring until all tension is
removed.
5. Remove the spring chamber bolts (28) and
remove the spring chamber (22).
a. If removing vertically, lift carefully to avoid
disturbing the spring (23) then remove
the spring guide (27) and spring (23).
b. If removing horizontally, it may be
necessary to
“tip” the spring chamber
(22) so the spring (23) and spring guide
(27) are removed along with the spring
chamber (22).
6. Mark the cover (2) and body (1) to ensure
proper alignment during re-assembly.
7. Remove the cover bolts (20) and remove the
cover
from
the
body.
All
remaining
components except the body seat (6) should
come out with the cover.
8. Using a chain/strap wrench, grasp the disc
(3) around its outside diameter, loosen and
remove the disc stem nut (7A). DO NOT
GRASP THE STEM (7) as any scoring will
damage the rod wiper (21).
9. Remove the disc stem washer (7C), piston
follower (15), the piston ID seal (16) and the
piston (12).
10. Remove the gland screws (11A) and gland
(11).
11. Extract the stem/disc assembly from the
cover.
12. Remove the disc seat ring screws (9), disc
seat ring follower (5) and disc seat ring (4).
13. Remove the two stem seals (19), lantern ring
(10) and rod wiper (21).
14. Typically, the piston bushing (14), upper
bushing (8) and lower bushing (8A) do not
need to be removed as the associated seals
can be replaced without removing these
components.
15. Inspect all parts for wear and damage.
Replace worn and/or damaged parts.
ASSEMBLY
The valve is reassembled by reversing the
disassembly sequence with consideration of the
following:
1a. Clean and polish all machined bearing and
sealing surfaces. Remove burrs and sharp
edges. Apply a light coat of lubricant to
assist in the assembly.
2a. Make sure the hole in the piston follower (15)
aligns with the pipe plug in the top of the
piston (12).
3a. Be especially careful when lowering the
cover assembly into the body to make sure
the cover seal (20) is not damaged.
4a. If spring chamber is vertical, place spring
(23) on piston follower (15) and spring guide
(27) on top of spring (23). Carefully lower
spring chamber (22) over spring (23),
replace spring chamber bolts (28) and
tighten.
7a. If spring chamber is horizontal, secure spring
guide (27) to top of spring (23) using duct
tape or other means. Slide spring and spring
guide into spring chamber until spring guide
(27) engages the adjusting stem (26).
Supporting the spring chamber, bring it up to
the cover, align bolt holes, install bolts and
tighten.
8a. Turn adjusting stem (27) clockwise until it is
at original position, tighten adjusting stem
lock nut (25).
9a. Install reservoir (24) and re-connect control
piping. Threaded connections should be
sealed with oil-compatible pipe sealant, not
Teflon tape. Open speed control valve fully
and slowly add oil to reservoir until it is ¾
full. If additional oil is needed, use non-
foaming AW32 hydraulic fluid.
10a. Reset closing speed control to original
position.
REPLACEMENT PARTS
Genuine replacement parts are available from your
local VAG/GA Industries representative or from the
factory:
VAG USA, LLC
234 Clay Avenue
Mars, PA 16046 USA
Telephone: 724-776-1020
Fax: 724-776-1254
E-mail:
Please have the nameplate data available when
ordering parts. Identify needed part(s) by Shop Order
(SO) Number, Figure Number, valve size and
individual part number.
Summary of Contents for GA INDUSTRIES Figure 624-D
Page 6: ...5...
