V5055A-F INDUSTRIAL GAS VALVES
9
60-2307—15
4.
Remove the leak test tap plug and connect the test
apparatus to the Leak Tap (
D
).
5.
Close the downstream manual gas cock (
E
).
6.
Open the upstream manual gas cock (
A
).
7.
Run the safety shutoff valve (
C
) to its fully open position
(through the safety system); then immediately
de-energize the system to close the valve.
8.
Immerse a 1/4 in. tube vertically 1/2 in. (12.7 mm) into
a jar of water.
9.
Slowly open the test petcock (
F
).
10.
When the rate of bubbles coming through the water
stabilizes, count the number of bubbles appearing
during a ten-second period. Each bubble appearing
during a ten-second period represents a flow rate of
approximately 0.001 cfh.
To meet U.S. requirements, leakage must not exceed the
values listed in Table 5.
Table 5. Allowable Leakage for V5055 Valves.
a
Based on natural gas at standard conditions, test pressures
provided by ANSI Z21.21, Section 2.4.2 and a maximum of
235 cc/hr (air) per inch of seal-off diameter. Seal-off diameter
is not to be confused with pipe size.
b
V5055F leakage rate is 1 bubble in 7.6 seconds.
NOTE: For international leak test requirements, contact
the office of the appropriate approval agency.
After the test:
11.
Close the upstream manual gas cock (A).
12.
Close the test petcock (F), remove the test apparatus,
and replace the leak test tap plug (D).
13.
Open the upstream manual gas cock (A) and energize
the safety shutoff valve (C).
14.
Test with soap bubbles to assure that there is no leak
at the test tap (D).
15.
De-energize the safety shutoff valve (C).
16.
Open the downstream manual gas cock (E).
17.
Restore the system to normal operation. If two safety
shutoff valves are utilized, each V5055 valve is to be
checked for tightness of closure.
SERVICE INFORMATION
WARNING
Explosion and Electrical Shock Hazard.
Can cause serious injury, death or property
damage.
1. Before servicing, turn off the gas supply and
disconnect all electrical power to the valve actuator.
2. Only qualified service technicians should attempt
to service or repair flame safeguard controls and
burner systems.
3. Do not disassemble the valve bonnet assembly;
the valve seat is not replaceable.
4. Failure to properly position and seat the seals in the
valve body may result in a hazardous gas leak.
Scheduled Inspection and Maintenance
Setup and follow a schedule for periodic inspection and
maintenance, including the burner, all other controls, and
the valve(s). It is recommended that the Valve Leak Test in
the Checkout section be included in this schedule. Refer to
the Instructions for the primary safety control for more
information.
Valve Bonnet Replacement
The entire valve bonnet may be replaced without removing
the valve body from the gas line. Do not disassemble the
valve bonnet assembly; the valve seat is not replaceable.
For part numbers, refer to Replacement Parts in the
Specifications section. Complete instructions for replacing
the bonnet assembly are included with the replacement part.
Replacement of Seals (Fig. 8 or 9)
When removing the bonnet to inspect and clean the valve,
install new seals (see Replacement Parts in Specifications
section). Coat the new seals with the grease provided, and
position them in the valve body as shown in Fig. 8 or 9.
Failure to properly position and seat the seals in the valve
body may result in a hazardous gas leak.
After the new bonnet assembly is installed, or the bonnet is
removed for any reason, check for gas leakage around the
bonnet seal. Turn on the gas at the manual valve. Paint the
seal area with a rich soap and water solution. Bubbles
indicate a gas leak. If a leak is detected, check to see that
the bonnet screws are tight. If necessary, turn off the gas
again and remove the bonnet to be sure the seals are
properly seated.
V5055 Pipe
Size (in.)
Allowable
leakage
(cc/hr)
a,b
Maximum
Number of
bubbles per 10
sec.
Minimum
Number of
Seconds for
10 bubbles
3/4, 1, 1-1/4,
1-1/2
573
14
6.7
2, 2-1/2, 3
940
24
4.1
4
1254
33
3.03
Содержание V5055A
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