Bolting for ANSI B16.5 & BS3293 Flanges – Dimensions

To suit R.F. Flange sizes DN 15 to 600 to ANSI B16.5 and DN 750 & 900 to BS3293

Diameter of Bolts is shown in inches. For nominal diameters 1 inch and smaller, threads are U.N.C.; nominal diameters 11/8 inch and larger threads are 8 U.N. (8 T.P.I.).

Length of Bolts (L) is shown in millimetres rounded to the nearest 5mm. Stud Bolt lengths (L*) do not include the height of points. Machine Bolt lengths (L) include the height of point.

The length shown includes the height of the Raised Face in all cases.

NOMINAL SIZES SHOWN ARE
V DN: SI METRIC TERM
I NPS: ANSI TERM

NOMINAL FLANGE SIZEPN20 (CLASS 150)PN50 (CLASS 300)PN100 (CLASS 600)PN150 (CLASS 900)PN250 (CLASS 1500)PN420 (CLASS 2500)NOMINAL FLANGE SIZE
No. BoltsDia. Bolts ins.LNo. BoltsDia. Bolts ins.LNo. BoltsDia. Bolts ins.LNo. BoltsDia. Bolts ins.LNo. BoltsDia. Bolts ins.LNo. BoltsDia. Bolts ins.L
Stud
Bolts mm
Mach.
Bolts mm
Stud
Bolts mm
Mach.
Bolts mm
Stud
Bolts mm
Stud
Bolts mm
Stud
Bolts mm
Stud
Bolts mm
V
DN
I
NPS
V
DN
I
NPS
15½4½60454½65554½80USE PN250 DIMENSIONS IN THESE SIZES4¾1054¾12515½
¾ 1
20¾4½655045/8756045/8904¾1154¾12520
2514½655545/8806545/89047/812547/814025
324½705545/8806545/810047/81254115032
404½70604¾907543/41054114041-1/817040
50245/8806585/8907585/810587/814581175502
6545/890758¾100858¾1208116081-1/819565
80345/890758¾110908¾12587/814581-1/818081-¼220803
9085/890758¾1109587/814090
100485/890758¾1109587/814581-1/817081-¼19581-½2551004
12558¾90808¾1201008116581-¼19081-½25081-¾3001255
15068¾1008512¾125105121170121-1/8195121-3/8260823451506
20088¾11090127/8140110121-1/8195121-3/8220121-5/82901223802008
25010127/811595161155130161-¼215161-3/8235121-7/8335122-½48525010
30012127/8120100161-1/8170145201-¼220201-3/8255162375122-¾54030012
35014121130110201-1/8175150201-3/8235201-½275162-¼405   35014
40016161135115201-¼190160201-½255201-5/8285162-½44540016
45018161-1/8150125241-¼195170201-5/8275201-7/8325162-¾49545018
50020201-1/8160135241-¼205180241-5/829020234516354050020
60024201-¼175145241-½230195241-7/8330202-½435163-½61560024
75030281-¼190160281-¾290250282355PN150, 250 & 420 – Not listed in BS 329375030
90036321½215180322325280282-½40090036

Raised Face height of 1.6mm for PN20 & 50 and 6.4mm for PN100, 150, 250 & 420 is included in dimension L (Bolt Length).

Material Specifications

ASTM A193 Grade B7
Standard specification for alloy steel and stainless steel bolting materials for high temperature service.
ASTM A194 Grade 2H
Standard specification for carbon and alloy steel nuts for bolts for high pressure and high temperature service.
ASTM A320
Standard specification for alloy steel bolting materials for low temperature service.
Grade L7 covers alloy steel stud bolts.
Grade L4 covers alloy steel nuts to suit Grade L7 stud bolts.