NYT 690 C04

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TEST SPECIFICATION NYT-690-C
CODE OF TESTS FOR TESTING COMBINED CUT-OUT COCK,
STRAINER, AND DIRT COLLECTORS
(AB TEST RACK)
 
ISSUE NO. 4 SPEC. NYT-690-C
DATE: AUGUST 6, 1993 2 PAGES
Diagrammatic view and arrangement of test rack is shown on
drawing NYT-690.
The following test plate and piping is required for making
the tests:
 AB-55 Test Plate PN. 747040 (Dwg. TA-2232-C)
OR
 AB-77 Test Plate PN. 747032 (Dwg. TA-2390)
 1" Blanking Flange PN. 740562 (Dwg. PF-314)
2 - 1" Fitting Gasket PN. 731056 (Dwg. BC-8378)
 1" Gripseal Fitting for
 3/4" Pipe Pc. 564349 (Dwg. BC-8578)
2 - 1/2" x 1-1/4" Hex Head
 Cap Screw PN. 744049 (Dwg. SA-65)
2 - 1/2" x 2" Head Head Bolts PN. 743254 (Dwg. QT-393)
2 - 1/2" Hex Nuts PN. 731020 (Dwg. BC-8231)
 3/4" x 6" Pipe Nipple Pc. 133155 (Dwg. PF-395)
Main reservoir feed valve must be set to close at 120 psi
pressure.
Supply pressure to be maintained at 140 psi pressure.
PRELIMINARY
Attach the AB-55 Test Plate to the test rack test stand.
Thread a 3/4" x 6" nipple into connection No. 2 of the test
plate. THREAD the 1" x 3/4" gripseal fitting onto the end of
the pipe nipple. Attach the combined cut-out cock, strainer,
and dirt collector on the flange of the gripseal fitting with a
1" fitting gasket placed in its groove in the face of the
fitting flange. Use the two (2) 1/2" x 1-1/4" hex head cap
ISSUE NO. 4 SPEC. NYT-690-C
DATE: AUGUST 6, 1993 2 PAGES
2
screws to attach the gripseal fitting to the device (cut-out
cock end as shown on attached drawing).
TEST NO. 1
LEAKAGE
Commence test with all cocks closed, Valve "A" handle in
Position No. 8, and cut-out cock handle in closed position.
Open Cock 9 and charge emergency reservoir to 120 psi
pressure. Open Cock 5, and operate cut-out cock handle several
times from "Closed" to "Open" position to properly seat the cock
key, finally leaving the handle in "Closed" position.
(a) Cock Key Leakage
Coat open end of Combined Cut-Out Cock, Strainer and Dirt
Collector with soap suds to detect leakage. Must hold a bubble
across opening for thirty (30) seconds.
Coat around top of cock key with soap suds to detect
leakage past "O" Ring seal. No leakage is permitted.
Attach 1" blanking flange to open end of device with a
fitting gasket and the two (2) 1/2" x 2" hex head bolts and
nuts. Move cock handle to "Open" position while moving handle
from "Open" position to "Closed" position several times, finally
leaving handle in "Open" position again. Coat around top of
cock key with soap suds to detect leakage by "O" ring seal. No
leakage is permitted.
(b) Casting, Cap Nut, and Gasket Leakage
Coat entire casting with soap suds to detect leakage. No
leakage is permitted.
At completion of test, close Cock 5 and open Cock 6 to
drain pressure from the device.
Remove Combined Cut-Out Cock, Strainer, and Dirt Collector
from test rack. Remove the blanking flange from the device.
With handle in "Open" position, note visually that cock key
waterway is fully open (not restricted).
ENGINEERING DEPARTMENT
REVISION PAGE
NYT-690-C
ISSUE NO. 1 Original Issue
April 1, 1974
ISSUE NO. 2 Removed "NS" and "Sump" from
February 11, 1982 entire code.
ISSUE NO. 3 Page 1 -
November 16, 1989 Converted WABCO No's. to NYAB
ISSUE NO. 4 Revised title to cover all valves.
AUGUST 6, 1993