Pound-Grade series safety valve's introduction
A. Relieving capacity calculation of safety valve Gas medium
1, Critical temperature:
     Ws=7.6×10-2 CKPdA:
2, Sub -critical temperature:
     Ws=55.84 KpdA:
Ws---
The draining ability of the safety valve, kg/h
K---
The draining coefficient elated with valve's structure. Can be supplied by the manufacturer or according to the following standards.
Full lift safety valve. K=0.60~0.70
Ting lift safety valve with the adjusting ring. K=0.4~0.5
Ting lift safety valve with no adjusting ring. K=0.25~0.35
Pd---
The draining pressure of safety valve (absolute pressure) Pd=1.1Ps+0.1, MPa
Ps---
The preset pressure of safety valve, MPa
Po---
The discharge side pressure of safety valve (absolute pressure), MPa
A---

Minimum draining transect of safety valve, mm2
Full lift safety valve,
Ting lift safety valve.
Plane seal, A=Dh; Cone seal, A=d1hsinΨ

h---
Lift height of safety valve, mm;
d1---
Minimum flow path diameter of safety valve, mm;
D---
Valve body diameter of safety valve, mm;
Ψ---
Half angle of cone seal.
C---
Feature coefficient of gas.
K---
Heat insulation coefficient of gas k=Cp/Cv
M---
Moore mass of gas, kg/kmol;
T---
Gas temperature
Z---
Compressed coefficient under the operation pressure
Liquid medium
Ws=5.1KA
P
Liquid density under the suction side temperature, kg/m3
P
The pressure difference of valve, MPa
           P=Pd-Po, Pd=1.2Ps+0.1 MPa;

B. Pound-Grade series safety valve's introduction Saturation vapor medium
Pd≤10Mpa
 Ws=5.25KAPd kg/h
 Pd=1.03Ps+0.1 MPa;
10Mpa<Pd
≤22Mpa
 
 Pd=1.03Ps+0.1 MPa

C. Pound-Grade series safety valve's introduction Value characteristic quotient of different K value gas
K C K C K C K C
1.00 315 1.20 337 1.40 356 1.60 372
1.02 318 1.22 339 1.42 358 1.62 374
1.04 320 1.24 341 1.44 359 1.64 376
1.06 322 1.26 343 1.46 361 1.66 377
1.08 324 1.28 345 1.48 363 1.68 379
1.10 327 1.30 347 1.50 364 1.70 380
1.12 329 1.32 349 1.52 366 2.00 400
1.14 331 1.34 351 1.54 368 2.20 412
1.16 333 1.36 352 1.56 369    
1.18 335 1.38 354 1.58 371    
Pound-Grade series safety valve's introduction The sealing request of API 527 standard
Set pressure(15.6℃) Allowed max. leakage (blebs per min.)
Throat diameter≤F Throat diameter≥F
1.03~68.69 40 20
103 60 30
132 80 40
172 100 50
207 100 60
276 100 80
385 100 100
414 100 100

SERVICE CARD
The technical data subject to amend without notice