pressure/teMporature tables (sec 4。2。J ), the service pressure shall be nn greater than lie pressure for Ltte lowest listed tempemture。 Consirleratiun should be given to the loss of ductilily and impact strength of many msLe\iets at w \emgeratu‹e。
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4。3Seat and seat rating
4。3。2The design shall be such that, when either polytetrBfluoro6thylene (F'TFE) or rcinfor«urI PTF E is usecl for seats, \h« minimum valve pressure/temperature rating shall as specified in Taf›l o 。
4。3。3Scat ratings fnr other seat matenals shall be ldc manufacturer’s standard, hr wever,
valvt S¢rvl¢e pressure/tem rature rating shall not exceed that of the valve shell。
Table 1— Minimum seat pressure/temperature rating
Pressure i bar (1 bar = 9, 1 MPa 。。 ]W I°« : 1 MPa - 1 N/mm+)
5。1Flow passageway
The for passagcway includes the circular sent opening in thu bolt and the bony nJns leading [hereto。 The
5。2。1Body wall thickness
5。2。1。1 The minimum valve body will thickness, / , sl1all be as specified in Table 8, eXcept that ror butt-welding end valves the welding ends for connection to pipo shall be in accordance with Figure 1
5'。2。2。2 The minimum thickness requiremet Is area licable to and are measured surfaces, i。e。 tfp to the point where body seals are effective。
Table 2 — Cylinder diameter for cal:ogortzIng boro size
Minimum bore diameter
Full bore Reduced bore Double reduced bore
NPSPN 10, 16, 25 and 40 — PN- Alf PH: All
Class 150 and 380 •rass ¥00 Clase。 All
NOTE Z For CTa ss BPO, only vaN'es hiring reduced port as w\\hfn Ohio scopo of Shia Intomallonal Standard。
s。2。1。3 I。r›caI areas having Ie!:« than minimum wall thickness arc acceptable provided Illat all cl fhe following conditions are satisfied。
—- lie measured thickness is not less than 0,75 › ;
5。2。2。1Body end flanges shall comply with tKe requirements of ASME B16。5 for Class-UCsigFl r+lC(\ V£\\tas
‹incl EN 109:2-1 for PN--rlesigi1ated valves。 Raised face end flanges shall be provided unless otherwise spccificcl by the p‹irct\aser。
5。2。2。2Face-to-inca rlimensior s fc r flanged end valves shall be in accordance with ASME B16。10 fnr Class-designate‹l valves or ISO 5752, Basic Sense 1, 14。 inn 27 for PN-designaled valves, with an
5。2。2。3Body or body cap end 9ango$ shalt be eltI1er cast or forged integral with tic budy nr end or rust or iorged flanges attached by full penetration butt•welding。 A purchaser requiring integral flange construction shall so po« i f y。 Whets a flange is a。tieched by welding。 it is required that II-e welding operator and '。'eluting procedure be ‹jualific'd ir› a« ur‹Jance v'ill1 the rules oT ASME-8PVC, Section IX or ihc rulers of ISO 95B6- 1 a fed 石油化工及相关金属球阀行业英文文献和中文翻译(3):http://www.youerw.com/fanyi/lunwen_96412.html