ITT Engineered Valves 903, Инструкция по установке, эксплуатации и обслуживанию

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3. Tighten the bonnet fasteners in a crisscross pattern.
For more information, see
4.2.1 Fastener torque table for valve body to topworks on page 9 .
4. Make multiple crisscross passes to build up torque to the final table value. Make additional criss-
cross passes using final table values to evenly tighten each fastener to within 5% of torque value.
5. Retighten the bonnet fasteners as noted above at ambient conditions after the system has cycled
through operating pressure and temperature.
6. Monitor the valve for leakage:
If leakage ... Then ...
Occurs at the body/bonnet
flange sealing area Depressurize the system and retighten the bonnet fasteners as noted
above.
Continues Depressurize the system and retighten the bonnet fasteners as noted
above. (maximum 3rd re-torque)
Continues Replace the valve diaphragm.
For more information, see 6.5 Replace the valve diaphragm on page 14 .
4.2.1 Fastener torque table for valve body to topworks
Table 1: PAS bonnet (963)
Values given are for lubricated fasteners.
Valve size, inches (DN) PTFE diaphragm Elastomer diaphragm
Inches DN in-lb N-m in-lb N-m
0.50 15 20-50 2.3-5.7 20-40 2.3-4.5
0.75 20 40-70 4.5-7.9 20-50 2.3-5.7
1.00 25 45-80 5.1-9.1 25-70 2.8-7.9
1.50 40 145-170 16-19 75-130 8.5-14.7
2.00 50 225-275 25-31 100-180 11-20
2.50 65 500-830 57-94 300-420 34-48
3.00 80 500-830 57-94 300-420 34-48
4.00 100 200-575 23-65 180-220 20-25
Table 2: Metal bonnet (903, 913)
Values given are for lubricated fasteners.
Valve size PTFE diaphragm Elastomer diaphragm
Inch DN in-lb N-m in-lb N-m
0.50 15 25-80 2.8-9.1 20-40 2.3-4.5
0.75 20 50-80 5.7-9.1 20-50 2.3-5.7
1.00 25 65-120 7.4-13.6 45-70 5.1-7.9
1.25 and 1.50 32 and 40 200-225 23-25 75-130 8.5-14.7
2.00 50 225-300 25-34 100-180 11-20
2.50 65 750-1000 85-113 300-420 34-48
3.00 80 750-1000 85-113 300-420 34-48
4.00 100 540-600 61-68 190-230 22-26
NOTICE:
1. Make multiple criss-cross passes to build up torque to final table values. Make addition-
al criss-cross passes using table vales to evenly tighten each bolt to within 5% of stated
torque.
4.2 Tighten the bonnet fasteners
Handwheel Operated Valves (903, 913, 963) Installation, Operation, and Maintenance Manual 9