GORMAN-RUPP VG3B3-B, Инструкция по установке, эксплуатации и обслуживанию

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A H E A D O F T H E F L O W
®
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NIBCO INC. WORLD HEADQUARTERS • 1516 MIDDLEBURY ST. • ELKHART, IN 46516-4740 • USA • PH: 1.800.234.0227
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4
Revised 5/19/2008
IV. VALVE INSTALLATION PROCEDURE - FLANGE, LUG & WAFER STYLE ONLY
Always position the connecting pipe flanges accurately in the line, allowing sufficient space between the flanges for the valve. Make
sure the pipe flange faces are clean of any foreign material such as scale, metal shavings or welding slag. Valves should be installed
with the disc in the closed position to prevent damage to sealing surfaces.
1. Carefully insert the valve between the pipe flanges. Do not apply any lubricants to the seat faces as this may damage them.
2. Line up, center and secure the valve between flanges using desired bolts or studs as listed in Table 4 on next page.
Do not tighten bolts at this time.
3. Carefully open the valve to assure free unobstructed disc movement. Disc interference may result when valves are installed in
pipelines having smaller than normal inside diameters, such as heavy wall pipe, plastic-lined pipe, as-cast flanges or reducing
flanges. Interference can also occur when connecting directly to a swing check or silent check. Suitable corrective measures must
be taken to remove these obstructions, such as taper boring the pipe or installing a spacer or spool piece.
4. After proper operation is verified, tighten the bolts to the minimum recommended bolt torques listed in Table 3 below using a
cross-over pattern, also shown below in Figure 3. NOTE: When installing valves NPS 14" and larger between two flanges, it is
recommended that the cartridge liner be evely compressed from both sides of the mating flanges. NIBCO recommends a
multi-stepped process utilizing the cross-over pattern be used to draw the flanges against the liner from both sides of the valve
at the same rate, ensuring the liner is compressed evenly. This method differs from the practice used on smaller valves, wherein
one flange side is completely tightened before moving to the opposite side.
5. Pressurize piping to valve and inspect for leakage. If leakage is observed, tighten bolts using
cross-over pattern, increasing torque until leak stops.
DO NOT EXCEED MAXIMUM TORQUES LISTED IN TABLE 3 BELOW.
6. Recommended torques are made without warranty. Installer must verify proper strength bolts
for application. Bolts shall be clean and un-lubricated.
Fig. 3
Suggested
Bolting Methods
Caution
1. Class 250 cast iron and Class 300 steel flanges can not be used on these valves.
2. Rubber faced or mechanical flanges are not recommended.
3. This valve is not recommended for steam service.
4. Valves should not be assembled to the flanges and then welded into the piping system.
5. Lever-lock handles are not recommended for use on 8" and larger valves.
6. Do not install valves with EPDM liner in compressed air lines.
Flange Bolt Minimum Bolt Maximum Bolt
Size Size Torque (ft.•lbs.) Torque (ft.•lbs.)
2"- 4" 5/8" 20 70
5"- 8" 3/4" 30 120
10" & 12" 7/8" 50 200
14" & 16" 1" 70 240
18" & 20" 1
1
/
8
" 100 380
24" - 30" 1
1
/
4
" 140 520
32"- 48" 1 1 /
2
" 200 800
Table 3
Recommended Bolt Tightening Torques
Bolt Tightening
Cross Over Pattern
2
1
3
8
6
5
7
4