Specifications | 1008A Valve
Valves for Gases, Oils, Steam, Compressed Air, Water. (For low pressure air valves, see Specifications 1004/1014.) All valves are for throttling control--not tight shutoff.
Materials of Construction
Grease Shaft
Max inlet pressure Maximum Minimum
Valve
Pipe size
(PSI)
Temp°F. Temp°F.
Body Core and Curtain Shaft
Seal Viton Viton
3⁄8 ", ½ "
1008A Valves
125 125 125
350 350 350
-20 -20 -20
BRS
316L SST 316L SST
SST SST SST
Litium #2 Litium #2
¾ " thru 2" 2- ½ " thru
DI
DI
316L SST
Litium #2
Viton
6"
1008A-S (steam)
Silicone
3⁄8 ", ½ "
125
350
-20
BRS
316L SST
SST
EP
compound Silicone compound Silicone compound Silicone compound
¾ " thru 2" 2- ½ " thru
125
350
-20
DI
316L SST
SST
EP
125
350
-20
DI
316L SST
SST
EP
6"
1010A-S (steam)
¾ " thru 3"
125
350
-20
BRS
Monel
SST
EP
Valves must be properly lubricated. See Sheet 1008A Instructions.
2 ½ ", 3" and 4" valves have ANSI flat face flanges cast into the body. 6" valves are furnished with ductile iron companion flanges. Materials abbreviations: BRS = brass, DI = ductile iron, SST = stainless steel.
SELECTION
Fluid
Pressure
Valve
Refer to
Air
0-3 psig
1004, 1014
Specifications 1004/1014
0-125 psig 0-125 psig
1008A 1008A
example below example below
Gas, Oil
Water Steam (saturated)
0-125 psig
1008A-S 1010A-S
example below
SIZING
psia = 0.8. Use Chart A. Density correction factor for 50 psia upstream pressure is 0.53 (from inset, Chart A). Corrected flow is 1225 scfm × 0.53 = 650 cfm. First diagonal line above inter- section of 10 psi pressure drop and 650 cfm lines on Chart A represents a 2" valve. Gas, 2 psig and up. Follow the same procedure as with 3-125 psig air, using Chart A for absolute pressure ratios of 0.7 and higher and Chart B for ratio of 0.69 or less. In either case, mul- tiply flow, scfm, by the appropriate gas gravity correction factor from the two-line table across the top of the inset on Chart A. Steam (saturated), up to 125 psig. (Specify "-S" model.) When ratio of downstream absolute pressure to upstream absolute pressure is 0.7 or greater, use same selection method as with 3-125 psig air, but select valve from Chart C. When pressure ratio is 0.69 or less, follow procedure for 3-125 psig air, but select valve from Chart D.
Air, 3-125 psig. Subtract desired high flow pressure drop from absolute upstream of the valve to get absolute pressure downstream of the valve. Divide this by upstream absolute pressure. If the result is 0.7 or more, refer to Chart A of this bulletin. Multiply the desired maximum air flow, scfm, by the appropriate density correction factor from the inset on Chart A, and locate the intersection of lines corresponding to corrected flow and pressure drop. The first diagonal line above this point indicates the correct valve size. If the ratio of downstream absolute pressure to upstream absolute pressure is 0.69 or less, read the intersection, on Chart B, of lines corresponding to upstream absolute pressure and flow, scfm ( do not multiply by the density correction factor). The first diagonal line above this point represents the correct size valve. Example: Select a valve to control 1225 scfm air in a 35 psig line. Maximum pressure drop across the wide open valve should be 10 psi. Pressure downstream of the valve will be (35 – 10) = 25 psig. Ratio of absolute pressures is (25 + 15) psia ÷ (35 + 15)
Bulletin 1008A/1010A Page 6
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