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。

US 20g4  - Al !  ti   /  ”。s  rescmcu

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