4
YARWAY
9100 SERIES ARC
®
VALVE
INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
DISASSEMBLY
2" to 8" [50 to 200 mm] valve sizes
1. For disassembly and inspection remove the
valve from the line. Match-mark the body
and bonnet to facilitate reassembly.
2. Remove the nuts attaching the valve bonnet
to the body.
3. Carefully lift straight up on the bonnet to
clear engagement of the disc stem.
4. The spring and disc assembly are now
exposed for easy removal.
5. Normally there is no need to remove
the bypass bushing. Should the bushing
be damaged, it may be removed by
straightening the lock washer tab. Remove
nut and lock washer. If necessary lightly tap
the bushing with a hammer and soft metal
rod. Be careful not to damage the threads
and bushing bore.
6. If the valve is fitted with an integral back
pressure regulator and the unit needs to
be replaced, carefully drill out the stake
mark in the plunger guide with a small drill.
Install draw bolt and washer (see Table 1
for sizes) and tighten until “snug.” Torque
= 5 to 10 ft./lb. [6.8 - 13.6 N•m]. Loosen the
remaining ring (clockwise) approximately
one turn and remove the spiral ring.
Partially remove the draw bolt. Pry under
the head of the draw bolt to remove the
regulator capsule.
7. If the valve is fitted with a flow conditioner
(31), it can be removed by pencil grinding the
tack welds and lifting the worn part from the
body (1).
1" to 1½" [25 to 40 mm] valve sizes
1. Follow Disassembly, step 1 for 2" to 8"
valves.
2. Remove the nuts attaching the valve bonnet
to the body, remove the bonnet.
3. Remove the bypass tube as follows: Drill
out the stake mark with a small drill. Use a
spanner wrench in the tube slots and turn
counterclockwise to remove. A 1" x 2" x ⅛"
[25 x 50 x 3 mm] thick steel plate and an
adjustable wrench may be used if a suitable
spanner wrench is not available.
4. Remove the disc-bypass bushing assembly
(Items 33, 34, 36, 37, 38, 39, 40, and 42) by
applying force to the bottom of the disc as
follows: Push on the bottom of the disc with
a 1" [25 mm] diameter bar until the spring
is fully compressed. Tap on the bar with a
mallet if additional force is required.
5. Lay the disc-bypass bushing assembly on a
flat surface with the bottom of the disc up.
Push down on the spring retainer (36) until
the spiral ring (38) is exposed. Remove the
spiral ring by inserting a screwdriver into
the ring removal notch and uncoiling the
ring over the shaft end. The assembly can
now be taken apart.
6. The main check flow element (29) does not
normally require maintenance. Should there
be a need to remove the flow element, lift
flow element evenly to prevent jamming
within the body. Light tapping around the
I.D. of the Flow element may be necessary
to free the part.
CAUTION
The back pressure regulator has an integral
spring and if the draw bolt is removed, it should
be done carefully. See separate instructions for
external back pressure regulator.
REPAIR AND INSPECTION
Inspect the condition of the body to bonnet
seal. Sealing surfaces must be free of defects.
Replace the elastomer seal each time the valve
is disassembled.
Examine the snubber-seal assembly for wear.
The snubber should project slightly beyond
guide diameter and with finger pressure should
compress and expand.
Examine the check valve seat for evidence of
wear. The surface can be reconditioned by
lapping (see Reassembly, step 6).
Supply the following information when ordering
spare parts:
(1) Figure Number
(2) Serial Number
(3) Type of fluid
Lock nut
Bonnet
Upper guide
bushing
Bypass
bushing
Spring
Snubber-seat
assembly
Disc
assembly
Stud
Lock nut
O-ring
O-ring
Body
