BS 1873:1975

Co-operating organizations
Foreword
Section 1 - General
1 Scope
2 References
3 Nomenclature
4 Pressure classification
5 Pressure/temperature ratings
6 Nominal sizes
7 Information to be supplied by the purchaser
Section 2 - Design
8 Body
9 Bonnet
10 Disk, disk nut and disk thrust plate
11 Yoke
12 Handwheel
13 Stem and yoke bushes
14 Stuffing box, packing and lantern ring
15 Bolting
16 Operation
17 Bypass
18 Soft seal rings
Section 3 - Materials
19 Shell
20 Body seat rings
21 Bonnet gasket
22 Disk
23 Yoke
24 Disk thrust plate
25 Handwheel or chainwheel
26 Handwheel or chainwheel nut
27 Yoke bush
28 Yoke bush retaining nut
29 Gland
30 Trim
31 Lantern ring
32 Stem packing
33 Bolting
34 Plugs
35 Nameplate
36 Soft seals
37 Special applications
Section 4 - Marking
38 Required markings
39 Body and nameplate markings
40 Body and bonnet markings
41 Nameplate markings
42 Additional markings
43 Body dividing wall marking
44 Omission of markings
Section 5 - Testing
45 Production pressure testing
Section 6 - Shipping
46 Preliminary
47 Preparation for despatch
48 Packaging
Appendix A - Particular dimensions for each
             class of valve
Appendix B - Application to piping systems
             with BS 4504 flanges
Publications referred to

Straight, angle and (oblique) Y pattern with flanged or butt-welding ends in nominal sizes from 15 to 400 mm (½ to 16 in) and Class 150 to 2500.

This British Standard specifies requirements for cast or forged carbon and alloy steel outside screw and yoke globe and globe stop and check valves, straight pattern, angle pattern and (oblique) Y pattern, with flanged or butt-welding ends in nominal sizes within the range of 15 mm to 400 mm (½ in to 16 in) and Classes 150 to 2500. This standard can also be used as a general guide where valves of material composition outside the scope of section three of this standard are required as, for example, for use in highly corrosive services or environments or for low temperatures (see clause 37).

The standard can be adapted to apply to valves with needle type seats in 15 mm (½ in) an 20 mm (¾ in) nominal sizes which will meet all requirements of this standard, except that the valve seat bore is reduced and the needle point may be either integral with or loose on the stem.