Appendix A2
Materials for Gate Valves
Working temperature
Temperature class | Operating range | |||
° F | ° C | |||
Min. | Max. | Min. | Max. | |
K | -70 | 180 | -60 | 82 |
L | -50 | 180 | -46 | 82 |
P | -20 | 180 | -29 | 82 |
R | Room temperature | Room temperature | ||
S | 0 | 150 | -18 | 66 |
T | 0 | 180 | -18 | 82 |
U | 0 | 250 | -18 | 121 |
V | 35 | 250 | 2 | 121 |
Working fluids (according with Material Class)
Fluids class | Partial pressure | |||
H2S | CO2 | API class material | ||
General service | Noncorrosive | <0,35 x 10-3 | <0,05 | AA |
Light corrosive | 0,05-0,21 | BB | ||
Temperature and high corrosive |
>0,21 | CC | ||
Sour service (in acc. With NACE MR-01 75) |
Noncorrosive | >0,35 x 10-3 | >0,05 | DD |
Light corrosive | 0,05-0,21 | EE | ||
Temperature and high corrosive |
>0,21 | FF |
Materials for Valves
AA | BB | CC | DD | EE | FF | |
Body | A487-4C A322-4130 |
A276-410 | A487-4C A322-4130 HB max. 235 |
A276-410 HB max.235 |
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Bonnet | A487-4C A322-4130 |
A276-410 | A487-4C A322-4130 HB max. 235 |
A276-410 HB max.235 |
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Stem | A322-4130 Nitride |
A276-410 Nitride |
A322-4130 HB max. 235 Nitride |
17-4PH (HRC 29-33) | ||
Gate | A276-410 HB max. 235 |
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Seat | ||||||
Studs and nuts | B7/2H or L7/2H1) | B7M/2HM or L7M/2HM1) | ||||
Ring gasket | API 6A/S4 | F 304L | API 6A/S4 | F 304L |
1) – only for Temp. class L, K