ISO 15761: Steel gate, globe and check valves for sizes DN 100 and smaller, for the petroleum and natural gas industries
ISO 15761 specifies the requirements for a series of compact steel gate, globe and check valves for petroleum and natural gas industry applications.
ISO 15761 is applicable to valves of:
一 nominal sizes DN 8, 10, 15, 20, 25, 32, 40, 50, 65, 80 and 100,
一 corresponding to nominal pipe sizes NPS 1/4, 3/8, 1/2, 3/4, 1-1/4, 1-1/2, 2, 2-1/2, 3 and 4,
一 pressure designations PN 16, 25, 40, 63, 100, 250 and 400, and
一 pressure designations Class 150, 300, 600, 800, 1500 and 2500.
Class 800 is not a listed class designation, but is an intermediate Class number widely used for socket welding and threaded end compact valves covered by this document.There is no equivalent PN designation.
This document includes provisions for the following valve characteristics:
一 outside screw with rising stems (OS&Y): in sizes 8≤DN≤100;
一 inside screw with rising stems (ISRS): in sizes 8≤DN≤65 with a pressure designation PN≤100 or Class≤800;
一 socket welding or threaded ends: in sizes 8≤DN≤65;
一 flanged or butt-welding ends excluding flanged end Class 800;
一 bonnet joint construction that is bolted, welded or threaded with seal weld;
一 bonnet joint construction that uses a union nut with a pressure designation PN≤45 or Class≤800;
一 body seat openings;
一 materials: as specified;
一 testing and inspection.
ISO 15761 covers valve end flanges in accordance with EN 1092-1 and ASME B16.5 and valve body ends having tapered pipe threads in accordance with ISO 7-1 or ASME B1.20.1. It is applicable to extended body construction in sizes 15≤DN≤50 with pressure designations Class 800 and Class 1500 and to bellows and bellows assembly construction adaptable to gate or globe valves in sizes 8≤DN≤50. Also covered are requirements for bellows stem seal type testing.
5 Design
5.1 Reference design
5.1.1 The reference design (the design to be provided when the purchaser does not specify otherwise or does not use Annex E)for sizes DN≤100 is for bolted bonnet or cover construction, an outside stem thread for gate and globe valves and, for globe valves having a conical disc.The reference design for threaded end valves is to use taper pipe threads in accordance with ASME B1.20.1.In addition, for valves
DN≤50 the reference design is to have the body and bonnet or cover to be forged material.
Valve parts are identified in Annex D.
5.1.2 Other configurations and types of material may be provided when specified in accordance with Annex E.Requirements for extended body valves given in Annex A and those for bellows stem seals in Annexes B and C shall be followed.
5.2 Flow passageway
5.2.1 The flow passageway includes the seat opening and the body ports leading thereto.The body ports are the intervening elements that link the seat opening to the end connection, e.g.socket or flange.
5.2.2 The minimum cross-sectional area requirement for the flow passageway applies for both the valve body ports and the seat opening in the absence of the valve obturator.The minimum flow passageway cross-sectional area shall not be less than that obtained using the equivalent diameters shown in Table 1 for standard bore and Table 2 for full bore valves.
Table 1—Minimum equivalent flow passageway diameter for a standard-bore valve
| PN designation | 16, 25, 40, 63, 100 | 250 | 400 | ||
| Class designation | 150, 300, 600, 800 | 1500 | 2500 | ||
| Gate, globe or check | Gate | Globe or check | Gate | Globe and check | |
| DN | Minimum equivalent diameter (mm) | ||||
| 8 | 6 | 6 | 5 | 6 | 5 |
| 10 | 6 | 6 | 5 | 6 | 4 |
| 15 | 9 | 9 | 8 | 9 | 8 |
| 20 | 12 | 12 | 9 | 10 | 9 |
| 25 | 17 | 15 | 14 | 13 | 13 |
| 32 | 23 | 22 | 20 | 18 | 18 |
| 40 | 28 | 27 | 25 | 25 | 25 |
| 50 | 36 | 34 | 27 | 26 | 25 |
| 65 | 44 | 38 | 34 | ||
| 80 | 50 | 47 | 42 | ||
| 100 | 69 | 63 | 58 | ||
Table 2 —Minimum equivalent flow passageway diameter for a full-bore valve
| PN designation | 16, 25, 40, 63, 100 | 250 | 400 | NPS | ||
| Class designation | 150, 300, 600, 800 | 1500 | 2500 | |||
| Gate, globe or check | Gate | Globe or check | Gate | Globe and check | ||
| DN | Minimum equivalent diam eter (mm) | |||||
| 8 | 6 | 6 | 4 | 6 | 4 | 14 |
| 10 | 6 | 9 | 7 | 9 | 7 | 38 |
| 15 | 12 | 12 | 9 | 10 | 9 | 42 |
| 20 | 17 | 15 | 14 | 13 | 13 | 34 |
| 25 | 22 | 22 | 19 | 18 | 18 | 1 |
| 32 | 28 | 26 | 25 | 25 | 25 | 114 |
| 40 | 35 | 34 | 26 | 26 | 25 | 12 |
| 50 | 44 | 38 | 34 | 35 | 30 | 2 |
| 65 | 50 | 47 | 42 | —— | 212 | |
Table 2 (continued)
| PN designation | 16, 25, 40, 63, 100 | 250 | 400 | NPS | ||
| Class designation | 150, 300, 600, 800 | 1500 | 2500 | |||
| Gate, globe or check | Gate | Globe or check | Gate | Globe and check | ||
| DN | Minimum equivalent diameter (mm) | |||||
| 80 | 69 | 63 | 58 | 3 | ||
| 100 | 95 | 92 | 87 | 4 | ||
5.3 Wall thickness
5.3.1 Except as provided in 5.3.2 and 5.3.3, the minimum wall thickness values for valve bodies and bonnets are given in Table 3.The manufacturer, taking into account such factors as bonnet bolting loads, rigidity needed for stem alignment, valve design details and the specified operating conditions, is responsible for determining if a larger wall thickness is required.
5.3.2 Valve body end connection minimum wall thickness shall be in accordance with 5.4.2, 5.4.3, 5.4.4, or 5.4.5 as applicable.Valves identified as extended body valves shall have body extension minimum wall thickness in accordance with A.3.Valves having bellows stem seals with a bellows enclosure shall have a bellows enclosure extension minimum wall thickness in accordance with B.4.
5.3.3 The bonnet minimum wall thickness for gate or globe valves, except for the neck extension that forms the packing chamber entryway, shall be in accordance with Table 3. The packing chamber extension shall have a local minimum wall thickness as specified in Table 4, based on the local inside diameter of the packing and stem hole.
5.4 Valve body
5.4.1 General
Requirements for a basic valve body and associated end connections are given here.The requirement for gate valve bodies having extended end present in Annex A shall be followed.
5.4.2 Socket welding ends
5.4.2.1 Exceptas maybe required herein, socket welding ends shall be in accordance with ASME B16.11.
5.4.2.2 The socket bore axis shall coincide with the end entry axis.Socket end faces shall be perpendicular to the socket bore axis.The socket bore diameter and its depth shall be in accordance with Table 5.
