BS_10-2009_Flanges

Page 1

Specification for flanges and bolting for pipes, valves and fittings

BS 10:2009

raising standards worldwide™

NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW

BSI British Standards

Page 2

BS 10:2009 BRITISH STANDARD

Publishing and copyright informationThe BSI copyright notice displayed in this document indicates when the document was last issued.

© BSI 2009

ISBN 978 0 580 61296 1

ICS 23.040.60

The following BSI references relate to the work on this standard: Committee reference PSE/15 Draft for comment 08/30174939 DC

Publication historyFirst published as BS 10-1:1947, BS 10-2:1926, BS 10-3:1929, BS 10-4:1931

and BS 10-5:1932First published as BS 10, December 1962Second (present) edition, April 2009

Amendments issued since publication

Date Text affected

Page 3

BRITISH STANDARD

© BSI 2009 • i

BS 10:2009

ContentsForeword iii1 Scope 12 Normative references 13 Design temperature and pressure 24 Designation 25 Flange dimensions 26 Flange materials 37 Attachment of flanges 48 Hydraulic testing of flange joints 49 Certification 410 Low temperature flanges and bolting 6

AnnexesAnnex A (informative) Information to be supplied by the purchaser 33Annex B (informative) Minimum requirements of steel to be used for flanges in Table A to Table H 34Annex C (normative) Bolts and nuts 37

Bibliography 41

List of figuresFigure 1 – Shaped stud bolt (see C.4) 25Figure 2 – Application diagram for bolts and stud-bolts: carbon and flanges 26Figure 3 – Steel or copper alloy plain flange 28Figure 4 – Steel boss flange 29Figure 5 – Integrally forged or cast steel flange for valves only 30Figure 6 – Steel welding neck flange (see Table D to Table T) 31Figure 7 – Integrally cast iron flanges (see Table F and Table H) 32

List of tablesTable 1 – Flange materials – minimum requirements 3Table 2 – Temperature/pressure ratings for carbon steel flanges [see Annex B] 5Table A – Dimensions of plain, boss, integrally cast or forged flanges (for ratings see Table 2 and Annex B) 7Table D – Dimensions of plain, boss, integrally cast or forged and welding neck flanges (for ratings see Table 2 and Annex B) 9Table E – Dimensions of plain, boss, integrally cast or forged, and welding neck flanges (for ratings see Table 2 and Annex B) 12Table F – Dimensions of plain, boss, integrally cast or forged, and welding neck flanges (for ratings see Table 2 and Annex B) 14Table H – Dimensions of plain, boss, integrally cast or forged, and welding neck flanges (for ratings see Table 2 and Annex B) 16Table J – Dimensions of plain, boss, integrally cast or forged, and welding neck flanges (for ratings see Table 2 and Annex B) 18Table K – Dimensions of plain, integrally cast or forged, and welding neck flanges (for ratings see Table 2 and Annex B) 19Table R – Dimensions of plain, integrally cast or forged, and welding neck flanges (for ratings see Table 2 and Annex B) 21Table S – Dimensions of plain, integrally cast or forged, and welding neck flanges (for ratings see Table 2 and Annex B) 22Table T – Dimensions of plain, integrally cast or forged, and welding neck flanges (for ratings see Table 2 and Annex B) 24Table B.1 – Grey cast iron properties 34Table B.2 – Temperature/pressure ratings for grey cast iron and malleable cast iron flanges [see Clauses 5g) and 5h)] 35

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BS 10:2009

ii • © BSI 2009

BRITISH STANDARD

Table B.3 – Temperature/pressure ratings for copper alloy flanges sizes 1⁄2 in to 3 in (inclusive) [see Clause 5j)] 35Table B.4 – Temperature/pressure ratings for copper alloy flanges sizes over 3 in [see Clause 5f)] 36Table C.1 – Application of bolts and stud-bolts [see Figure 2a) and Figure 2b)] 37Table C.2 – Materials, dimensions and finish of bolts, stud-bolts and nuts 39

Summary of pagesThis document comprises a front cover, an inside front cover, pages i to iv, pages 1 to 42, an inside back cover and a back cover.

Page 5

BRITISH STANDARD

© BSI 2009 • iii

BS 10:2009

Foreword

Publishing information

This British Standard is published by BSI and came into effect on 30 April 2009. It was prepared by Technical Committee PSE/15, Flanges. A list of organizations represented on this committee can be obtained on request to its secretary.

Supersession

This British Standard supersedes BS 10:1962, which is withdrawn.

Information about this document

It should be noted that, apart from cast iron flanges, the hydraulic test pressure applied to a flange joint is limited to one-and-a-half times the highest rated pressure of the flange (see Clause 8).

This is a full revision of the standard, and introduces the following principal changes:

• Materials have been updated;

• The standard has been re-arranged to reflect the most common used materials and types in service;

• Review of tables:

BS 10 flanges have been in use since 1904 and have been developed continuously to meet increasing pressure and temperature requirements. At the time of this revision, flange joints with carbon steel pipe flanges for high temperatures and pressures to the British Standard tables have been in service throughout the world for periods equal to the economic life of primary plant. The tables have therefore remained in the standard for guidance.

NOTE When it is required to convert the figures in this standard from imperial units into metric units it is recommended that the conversion factors and the table of conversion contained in BS 350, “Conversion factors and tables”, be used. Attention is also drawn to BS 2856, “Precise conversion of inch and metric sizes on engineering drawings”. (Use 1 in = 25 mm when converting to metric dimensions.)

Presentational conventions

The provisions of this standard are presented in roman (i.e. upright) type. Its requirements are expressed in sentences in which the principal auxiliary verb is “shall”.

Commentary, explanation and general informative material is presented in smaller italic type, and does not constitute a normative element.

Contractual and legal considerations

This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.

Compliance with a British Standard cannot confer immunity from legal obligations.

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BS 10:2009

iv • © BSI 2009

BRITISH STANDARD

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BRITISH STANDARD

© BSI 2009 • 1

BS 10:2009

1 ScopeThis British Standard specifies requirements for a series of carbon steel, alloy steel, cast iron and copper alloy flanges, and also appropriate bolts and nuts, for use with pipes, valves and fittings containing steam, oil, compressed air or water.

NOTE 1 The use of flanges complying with this standard for temperatures below −17.8 °C (0 °F) should be agreed between purchaser and manufacturer. These flanges may also be used on pipes, valves and fittings carrying other fluids for which the same requirements for safety and joint tightness are appropriate.

The applicability relationship between temperature and pressure for the above materials is specified for each table of flanges in Table 2 and Annex B.

NOTE 2 The types of gasket, and gasket materials, and the surface finish of the jointing face are matters for agreement between the purchaser and the manufacturer. When a raised jointing face is specified the outside diameter of the gasket should extend at least to the outside diameter of the raised face. For steel flanges when a raised jointing face is not specified, the gasket should be within the bolt holes.

2 Normative referencesThe following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

BS 21, Specification for pipe threads for tubes and fittings where pressure-tight joints are made on the threads (metric dimensions)

BS 84, Parallel screw threads of Whitworth form – Requirements

BS 916, Specification for black bolts screws and nuts – Hexagon & square, with B.S.W. threads, and partly machined bolts, screws & nuts, hexagon & square with B.S.W. or B.S.F. threads

BS 1580-1, Unified screw threads – Part 1: Screw threads with diameters 1⁄4 in and larger – Requirements

BS 1769, Specification for unified black hexagon bolts, screws and nuts – (UNC and UNF threads) – heavy series

BS 3410, Specification for metal washers for general engineering purposes

BS EN 10090, Wrought steels in the form of bars, billets, and forgings, up to 6 in ruling section, for automobile and general engineering purposes – En series

BS EN 10025-2, Hot rolled products of structural steels – Part 2: Technical delivery conditions for non-alloy structural steels

BS EN 10222-2, Steel forgings for pressure purposes – Part 2: Ferritic and martensitic steels with specified elevated temperature properties

BS EN 13480 Parts 1-5, Metallic industrial piping

BS EN 14324, Brazing – Guidance on the application of brazed joints

BS EN 10204, Metallic products —˜– Types of inspection documents

Page 8

BS 10:2009

2 • © BSI 2009

BRITISH STANDARD

3 Design temperature and pressure3.1 The design temperature and pressure shall be stated by the purchaser. The tables provided in this standard are for guidance only and are based on historical data contained in previous revisions of this standard. If verification is required, this shall be the responsibility of the purchaser. One method of verification that could be used is BS EN 1591-1.

3.2 Where there is an appropriate application standard the purchaser shall ensure that the design temperature and pressure stated conform to the requirements of that standard.

NOTE The temperature-pressure ratings given in Table 2 and Annex B are design temperatures and pressures.

3.3 The pressure ratings, with the exception of those in the second column in Table B.2, shall be applied to installations subject to moderate shock such as might occur in an efficiently designed and operated boiler feed main.

3.4 Where a system might be subject to more severe shock, the purchaser shall make a suitable allowance when stating the design pressure or the flange table.

4 DesignationFlange sizes shall be designated by the nominal bores of their respective pipes as given in the first and last column of each table.

5 Flange dimensions

5.1 GeneralFlange dimensions shall conform to those specified in the appropriate tables and Figure 3 to Figure 7.

NOTE The thicknesses and diameters of flanges specified are minima.

5.2 Raised jointing faces for steel flanges only (see Figure 3 to Figure 6)NOTE 1 Raised jointing faces specified in Table H, Table J and Table K are recommended only for steel flanges.

If a raised jointing face is required on a steel flange specified in Table A, Table D, Table E and Table F, the diameter shall be 1⁄4 in less than the diameter of the inscribed circle touching the bolt holes.

NOTE 2 Raised jointing faces are not specified in Table H, Table J and Table K because it is not customary to use them on these flanges.

Raised jointing faces as specified in Table R, Table S and Table T shall be used.

5.3 Flange thicknesses (see Figure 3 to Figure 7)NOTE 1 The thickness (T) specified in the tables includes a raised jointing face having a height not exceeding 1⁄16 in. Where there is no raised face, T is the thickness of the flange. If the height of the raised jointing face is more than 1⁄16 in, the thickness (T) is increased by an equivalent amount.

The backs of integrally cast steel flanges shall be machined.

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BRITISH STANDARD

© BSI 2009 • 3

BS 10:2009

NOTE 2 This machining may be either by spot-facing at the bolt holes or by back-facing at the option of the manufacturer (see Figure 5). The backs of other flanges may be left unmachined at the option of the manufacturer unless otherwise specified by the purchaser.

After machining, the thickness of the flange shall be not less than the thickness specified.

5.4 Flange drillingUnless otherwise specified by the purchaser all bolt holes shall be drilled, shall be equally spaced on the bolt pitch circle diameter, and in the case of integral flanges the bolt holes shall be drilled off centres.

For 1⁄2 inch and 5⁄8 inch bolts, the diameters of the holes shall be 1⁄16 inch larger than the diameters of the bolts, except that for cast iron flanges with 5⁄8 inch bolts the holes can be 1⁄8 inch larger than the diameters of the bolts. For 3⁄4 inch bolts and larger, the diameter of the holes shall be not greater than 1⁄8 inch larger than the diameters of the bolts in all cases.

6 Flange materials6.1 Steel flanges either forged, stamped or plate shall be manufactured from materials conforming to the minimum requirements as set out in Table 1.

NOTE Alternative materials can be used providing that the mechanical properties at operating temperature are not inferior to those given in the specifications set out in Table 1.

Table 1 Flange materials – minimum requirements

Flange table Temperature range −17.8 °C to 427 °C inc. (0 °F to 800 °F inc.)

A to J inclusive BS EN 10025-2, S235JR

K to T inclusive BS EN 10025-2, S275JR BS EN 10222-2, P245GH

NOTE For the minimum requirements of steel that can be used for flanges in Table A to Table H inclusive for temperatures from −17.8 °C (0 °F) to 260 °C (500 °F), see Annex B.

6.2 Flanges shall be free from laminations and surface defects.

6.3 Where welding neck flanges are made from wrought steel the direction of the fibres of the material in the neck shall be parallel to the longitudinal axis of the flange.

6.4 If the purchaser requires certificates of the process, chemical analysis of the specified elements and physical properties of the materials, this shall be stated on the order.

6.5 When the purchaser requires the individual flange he has ordered to be marked to identify the materials used, the system of marking to be employed shall be the subject of agreement between the purchaser and the manufacturer.

Page 10

BS 10:2009

4 • © BSI 2009

BRITISH STANDARD

7 Attachment of flanges7.1 The method of securing flanges (other than integral flanges) to pipes and fittings supplied complete by manufacturers shall be in accordance with the appropriate application standard. Where there is no appropriate application standard, the methods of attachment shall be the subject of agreement between the purchaser and the manufacturer.

NOTE Where there is no appropriate application standard, the methods shown in BS EN 13480, Parts 1 to 5 and BS EN 12449 should be regarded as minimum requirements.

7.2 If flanges are to be supplied loose, they shall, unless otherwise specifically called for by the purchaser, be prepared for attachment to pipes as follows.

a) Steel flanges.

1) Boss flanges, sizes 6 in and smaller, screwed in accordance with BS 21.

2) Boss flanges, sizes 7 in to 12 in machined in the bore to slip over the outside diameter of the pipe or fitting; suitable for welding.

3) Plain flanges 1⁄2 in thick and thicker, machined in the bore; suitable for welding-on to form one of the types in the appropriate application standard as required by the purchaser. The purchaser shall specify the type of preparation required.

4) Welding neck flanges, machined in the bore to a diameter to be specified by the purchaser, and suitably bevelled for welding to pipes or fittings.

b) Copper alloy flanges. Machined in the bore to slip over the outside diameter of the pipe or fitting; suitable for fusion welding (where applicable).

8 Hydraulic testing of flange joints8.1 This standard does not specify the hydraulic test pressures for flanged pipes or components, details of which shall be obtained from the appropriate standards which specify test pressures for pipes or components but in any case, the test pressure to be applied to the joint shall not exceed one-and-a-half times the highest rated pressures for steel and copper alloy flanges, and twice the highest rated pressures for cast iron flanges.

8.2 Where flanged assemblies are not covered by any standard specifying test pressures but incorporate flanges conforming to this standard, or where any assembly is to be used for duties of a special nature, the test pressure shall be agreed between the purchaser and the manufacturer.

9 CertificationThe flange manufacturer shall use respective procedures to ensure material traceability and to avoid material exchange and shall be able to provide retrospective certification for the base material used. Certificates shall be provided in accordance with BS 10204, ENType 2.1 as a minimum but the purchaser may also request a 2.2 or 3.1 certificate at their option.

Page 11

BRITISH STANDARD

© BSI 2009 • 5

BS 10:2009

Tab

le 2

Te

mp

erat

ure

/pre

ssu

re r

atin

gs

for

carb

on

ste

el fl

ang

es [

see

An

nex

B]

Tab

leTe

mp

erat

ure

°C

Max

imu

m

hyd

rau

lic

test

p

ress

ure

(l

bf/

in2 )

−17

.8 t

o

121.

1−

17.8

to

23

2.2

260.

028

7.8

315.

634

3.3

371.

139

942

7

Tem

per

atu

re °

F

0 to

250

0 to

450

500

550

600

650

700

750

800

Pres

sure

(lb

f/in

2 )

A50

A)

25 B

)—

——

——

——

75

D—

100

9585

8070

6555

5015

0

E—

200

185

170

155

140

130

115

100

300

F—

300

280

255

235

215

195

170

150

450

H—

500

465

430

395

355

320

285

250

750

J—

700

650

600

550

500

450

400

350

1 05

0

K—

900

835

770

705

645

580

515

450

1 35

0

R—

1 20

01

115

1 03

094

585

577

068

560

01

800

S—

1 80

01

670

1 54

51

415

1 28

51

155

1 03

090

02

700

T—

2 80

02

600

2 40

02

200

2 00

01

800

1 60

01

400

4 20

0

NO

TE

Inte

rmed

iate

val

ues

ab

ove

450

°F (

232.

2°C

) m

ay b

e o

bta

ined

by

linea

r in

terp

ola

tio

n.

A)

It is

cu

sto

mar

y in

th

e g

as in

du

stry

to

lim

it t

he

use

of

Tab

le A

flan

ges

to

wo

rkin

g g

as p

ress

ure

s n

ot

exce

edin

g 3

0 lb

f/in

2 . It

is r

eco

mm

end

ed t

hat

th

is li

mit

atio

n b

e al

so

app

lied

to

co

mp

ress

ed a

ir.B

) Th

is r

atin

g a

pp

lies

to t

emp

erat

ure

s ab

ove

121

.1 °

C (

250

°F)

up

to

an

d in

clu

din

g 2

32.2

°C

(45

0 °F

) an

d d

oes

no

t ap

ply

to

flan

ge

size

s ab

ove

36

in.

Page 12

BS 10:2009

6 • © BSI 2009

BRITISH STANDARD

10 Low temperature flanges and boltingCOMMENTARY ON CLAUSE 10Alternative materials may be used provided that the mechanical properties at operating temperature are not inferior to those given in the specifications referred to below.

Flanges and bolting for low temperature duty shall conform to the following minimum requirements.

a) Steel flanges either plate, stamped, forged or cast and bolting material intended for use with pipes in accordance with BS 3603. Pressure ratings for these shall be stated by the purchaser.

b) Where copper alloy flanges to this standard are used for temperatures down to −200 °C (−328 °F), pressure ratings for these flanges shall be stated by the purchaser. Guidance is provided in Table B.3 or Table B.4, temperature range −17.8 °C to 121.1 °C (0 °F to 250 °F), and is based on historical data contained in previous revisions of this standard.

NOTE 9% aluminium bronze to BS 2032 is a suitable bolting material for the above low temperature range, but other copper alloys may be used by agreement between the purchaser and the supplier.

Page 13

BRITISH STANDARD

© BSI 2009 • 7

BS 10:2009

Tab

le A

D

imen

sio

ns

of

pla

in, b

oss

, in

teg

rally

cas

t o

r fo

rged

flan

ges

(fo

r ra

tin

gs

see

Tab

le 2

an

d A

nn

ex B

)

Flan

ge

size

d

esig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

xim

ate

ou

tsid

e d

iam

eter

of

stee

l pip

e A

)

Dia

met

er

of

flan

ge

Bo

lt c

ircl

e d

iam

eter

No

. of

bo

lts

Dia

met

er

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(Fi

g 4

) C

)Th

ickn

ess

of

flan

ge

Bo

ss

len

gth

Dia

met

er

at s

mal

l en

d o

f b

oss

Max

imu

m

dia

met

er

at r

oo

t o

f b

oss

Gre

y ca

st ir

on

in

teg

rally

ca

st o

r sc

rew

ed o

n

wit

h b

oss

Mal

leab

le

cast

iro

n

scre

wed

on

w

ith

bo

ss

Co

pp

er a

lloy

cast

or

wro

ug

ht

inte

gra

l or

bo

ss

or

pla

in (

Fig

. 3)

Wro

ug

ht

stee

l in

teg

ral o

r p

lain

(F

ig. 3

) o

r b

oss

(F

ig. 4

)

HL

PN

OA

BE

T 1T 2

T 3T 4

inin

inin

inin

inin

inin

inin

27 ⁄3

23

3 ⁄42

5 ⁄84

1 ⁄2 3⁄8

1 5 ⁄1

61

1 ⁄2 1⁄2

3 ⁄16

1⁄4

3⁄16

D)

3⁄4

1 1 ⁄1

64

2 7 ⁄8

41 ⁄2

7⁄16

1 1 ⁄2

1 3 ⁄4

1⁄2

3 ⁄16

1⁄4

3⁄16

D)

11

11⁄32

4 1 ⁄2

3 1 ⁄4

41 ⁄2

7⁄16

1 7 ⁄8

2 1 ⁄1

6 1⁄2

3 ⁄16

5⁄16

3⁄16

D)

1 1 ⁄4

1 11

⁄164

3 ⁄43

7 ⁄16

41 ⁄2

7⁄16

2 3 ⁄1

62

9 ⁄32

5⁄8

1 ⁄4 5⁄16

1⁄4

D)

1 1 ⁄2

1 29

⁄325

1 ⁄43

7 ⁄84

1 ⁄2 1⁄2

2 7 ⁄1

62

3 ⁄4 5⁄8

1 ⁄4 3⁄8

1⁄4

D)

22

3 ⁄86

4 1 ⁄2

45 ⁄8

1⁄2

2 15

⁄163

1 ⁄8 5⁄8

5 ⁄16

3⁄8

5⁄16

D)

2 1 ⁄2

36

1 ⁄25

45 ⁄8

5⁄8

3 9 ⁄1

63

21⁄32

11 ⁄1

65 ⁄1

6 7⁄16

5⁄16

D)

33

1 ⁄27

1 ⁄45

3 ⁄44

5 ⁄8 5⁄8

4 3 ⁄1

64

13⁄32

11 ⁄1

63 ⁄8

1⁄2

3⁄8

D)

3 1 ⁄2

48

6 1 ⁄2

45 ⁄8

11 ⁄1

64

11⁄16

5 1 ⁄8

3⁄4

3 ⁄8 9⁄16

3⁄8

D)

44

1 ⁄28

1 ⁄27

45 ⁄8

3⁄4

5 1 ⁄4

5 1 ⁄2

3⁄4

3 ⁄8 5⁄8

3⁄8

D)

55

1 ⁄210

8 1 ⁄4

45 ⁄8

3⁄4

6 5 ⁄1

66

3 ⁄4 3⁄4

1 ⁄2 1

1 ⁄16

1⁄2

66

1 ⁄211

9 1 ⁄4

45 ⁄8

3⁄4

7 5 ⁄1

67

3 ⁄4 1

3 ⁄16

1 ⁄2 1

1 ⁄16

1⁄2

6 5 ⁄8

77

5 ⁄812

10 1 ⁄4

85 ⁄8

7⁄8

8 3 ⁄8

8 3 ⁄4

13 ⁄1

6—

3⁄4

1⁄2

88

5 ⁄813

1 ⁄411

1 ⁄28

5 ⁄8 7⁄8

9 1 ⁄2

10 7⁄8

— 3⁄4

1⁄2

99

5 ⁄814

1 ⁄212

3 ⁄48

5 ⁄81

10 1 ⁄2

11 1 ⁄8

7⁄8

— 3⁄4

5⁄8

1010

3 ⁄416

148

3 ⁄41

1 ⁄16

11 3 ⁄4

12 3 ⁄1

6 1

5 ⁄16

— 3⁄4

5⁄8

1212

3 ⁄418

168

3 ⁄41

1 ⁄813

3 ⁄414

3 ⁄16

15 ⁄1

6—

7⁄8

3⁄4

1314

19 1 ⁄4

17 1 ⁄4

83 ⁄4

——

— 1

5 ⁄16

— 7⁄8

3⁄4

1415

20 3 ⁄4

18 1 ⁄2

87 ⁄8

——

—1

—1

7⁄8

1516

21 3 ⁄4

19 1 ⁄2

87 ⁄8

——

—1

—1

7⁄8

16—

22 3 ⁄4

20 1 ⁄2

127 ⁄8

——

—1

1 ⁄16

—1

7⁄8

1718

2421

3 ⁄412

7 ⁄8—

——

1 1 ⁄1

6—

1 1 ⁄1

6 7⁄8

18—

25 1 ⁄4

2312

7 ⁄8—

——

1 1 ⁄1

6—

1 1 ⁄1

6 7⁄8

1920

26 1 ⁄2

2412

7 ⁄8—

——

1 1 ⁄8

—1

1 ⁄8 7⁄8

20—

27 3 ⁄4

25 1 ⁄4

127 ⁄8

——

—1

1 ⁄8—

1 1 ⁄8

1

2122

2926

1 ⁄212

7 ⁄8—

——

1 1 ⁄8

—1

1 ⁄81

Page 14

BS 10:2009

8 • © BSI 2009

BRITISH STANDARD BRITISH STANDARD

© BSI 2009 • 9

BS 10:2009Ta

ble

A

Dim

ensi

on

s o

f p

lain

, bo

ss, i

nte

gra

lly c

ast

or

forg

ed fl

ang

es (

for

rati

ng

s se

e Ta

ble

2 a

nd

An

nex

B)

(co

nti

nu

ed)

Flan

ge

size

d

esig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

xim

ate

ou

tsid

e d

iam

eter

of

stee

l pip

e A

)

Dia

met

er

of

flan

ge

Bo

lt c

ircl

e d

iam

eter

No

. of

bo

lts

Dia

met

er

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(Fi

g 4

) C

)Th

ickn

ess

of

flan

ge

Bo

ss

len

gth

Dia

met

er

at s

mal

l en

d o

f b

oss

Max

imu

m

dia

met

er

at r

oo

t o

f b

oss

Gre

y ca

st ir

on

in

teg

rally

ca

st o

r sc

rew

ed o

n

wit

h b

oss

Mal

leab

le

cast

iro

n

scre

wed

on

w

ith

bo

ss

Co

pp

er a

lloy

cast

or

wro

ug

ht

inte

gra

l or

bo

ss

or

pla

in (

Fig

. 3)

Wro

ug

ht

stee

l in

teg

ral o

r p

lain

(F

ig. 3

) o

r b

oss

(F

ig. 4

)

HL

PN

OA

BE

T 1T 2

T 3T 4

inin

inin

inin

inin

inin

inin

22—

3027

1 ⁄212

1—

——

1 3 ⁄1

6—

1 3 ⁄1

61

2324

3128

1 ⁄212

1—

——

1 3 ⁄1

6—

1 3 ⁄1

61

24—

32 1 ⁄2

29 3 ⁄4

121

——

—1

3 ⁄16

—1

3 ⁄16

1

2626

33 1 ⁄4

30 3 ⁄4

161

——

—1

1 ⁄4—

—1

2728

34 1 ⁄4

31 3 ⁄4

161

——

—1

1 ⁄4—

—1

2930

36 1 ⁄4

33 3 ⁄4

201

——

—1

1 ⁄4—

—1

30—

37 1 ⁄4

34 3 ⁄4

201

——

—1

1 ⁄4—

—1

3334

40 1 ⁄2

3820

1—

——

1 1 ⁄4

——

1 1 ⁄8

3536

42 1 ⁄2

4024

1—

——

1 1 ⁄4

——

1 1 ⁄8

36—

43 1 ⁄2

4124

1—

——

1 3 ⁄8

——

1 1 ⁄8

3940

46 1 ⁄2

4424

1—

——

1 3 ⁄8

——

1 1 ⁄8

4243

49 1 ⁄2

4728

1—

——

1 3 ⁄8

——

1 1 ⁄4

45—

52 3 ⁄4

50 1 ⁄4

281

——

—1

1 ⁄2—

—1

1 ⁄4

4849

55 3 ⁄4

53 1 ⁄4

281

——

—1

1 ⁄2—

—1

1 ⁄4

5455

63 1 ⁄4

60 1 ⁄4

321

1 ⁄4—

——

1 3 ⁄4

——

1 3 ⁄8

6061

70 1 ⁄4

6732

1 1 ⁄4

——

—1

7 ⁄8—

—1

1 ⁄2

6667

1 ⁄476

1 ⁄273

1 ⁄432

1 1 ⁄4

——

—2

1 ⁄8—

—1

5 ⁄8

7273

1 ⁄483

79 1 ⁄2

361

3 ⁄8—

——

2 3 ⁄8

——

1 3 ⁄4

A)

(H)

For

avai

lab

ility

of

stee

l pip

e si

zes,

ref

er t

o B

S EN

102

16, B

S EN

102

17. S

ee B

S 46

22 a

nd

BS

4722

fo

r o

uts

ide

dia

met

ers

of

cast

iro

n p

ipes

. See

BS

EN 1

2449

fo

r th

e si

zes

of

cop

per

pip

es f

or

use

wit

h c

op

per

allo

y fl

ang

es u

p t

o 8

in b

ore

.B

) (O

) Fo

r 1 ⁄2

in a

nd

5 ⁄8 in

bo

lts,

th

e d

iam

eter

s o

f th

e h

ole

s sh

all b

e 1 ⁄1

6 in

larg

er t

han

th

e b

olt

s an

d f

or

3 ⁄4 in

bo

lts

and

siz

es a

bo

ve, t

he

dia

met

ers

shal

l be

no

t m

ore

th

an 1 ⁄8

in la

rger

th

an t

he

bo

lts.

Fo

r ca

st ir

on

flan

ges

th

e d

iam

eter

s o

f th

e b

olt

ho

les

may

be

1 ⁄8 in

larg

er t

han

th

e b

olt

s o

f si

zes

5 ⁄8 in

an

d a

bo

ve.

For

7 ⁄8 in

bo

lts

and

siz

es a

bo

ve, t

he

dia

met

ers

shal

l be

no

t m

ore

th

an 1 ⁄8

in la

rger

th

an t

he

bo

lts.

C)

(A, B

an

d E

) Ta

per

s ar

e n

ot

spec

ified

bu

t sh

all b

e su

ch t

hat

th

e m

axim

um

dia

met

ers

at r

oo

t o

f b

oss

are

no

t ex

ceed

ed.

D)

(T4)

It is

imp

ract

icab

le t

o u

se t

hic

knes

s le

ss t

han

1 ⁄2 in

exc

ept

for

bo

ss a

nd

inte

gra

l flan

ges

.

Page 15

BS 10:2009

8 • © BSI 2009

BRITISH STANDARD BRITISH STANDARD

© BSI 2009 • 9

BS 10:2009

Tab

le D

D

imen

sio

ns

of

pla

in, b

oss

, in

teg

rally

cas

t o

r fo

rged

an

d w

eld

ing

nec

k fl

ang

es (

for

rati

ng

s se

e Ta

ble

2 a

nd

An

nex

B)

Flan

ge

size

des

-ig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

x-im

ate

ou

tsid

e d

iam

-et

er o

f st

eel

pip

e A

)

Dia

m-

eter

of

flan

ge

Bo

lt

circ

le

dia

m-

eter

No

. o

f b

olt

s

Dia

m-

eter

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(F

ig 4

) C

)D

imen

sio

ns

of

nec

ks f

or

cast

ir

on

(Fi

g. 7

)

Dim

ensi

on

s o

f st

eel w

eld

ing

n

ecks

(Fi

g. 6

)Th

ickn

ess

of

flan

ge

Bo

ss

len

gth

Dia

m-

eter

at

smal

l en

d

of

bo

ss

Max

i-m

um

d

iam

-et

er a

t ro

ot

of

bo

ss

Dia

m-

eter

at

larg

e en

d

of

nec

k

Len

gth

o

f ta

per

Dia

m-

eter

at

larg

e en

d

of

nec

k

Dia

m-

eter

at

smal

l en

d o

f n

eck

D)

Tota

l le

ng

th

of

nec

k

Len

gth

o

f ta

per

Gre

y ca

st ir

on

in

te-

gra

lly

cast

or

scre

wed

o

n w

ith

b

oss

Co

pp

er

allo

y ca

st o

r w

rou

gh

t in

teg

ral

or

bo

ss

or

pla

in

(Fig

. 3)

Wro

ug

ht

stee

l in

teg

ral

or

pla

in

(Fig

. 3)

or

bo

ss

(Fig

. 4)

or

wel

din

g

nec

k (F

ig. 6

) (e

xcep

t fo

r va

lves

)

Cas

t st

eel

inte

gra

l o

r p

lain

(F

ig. 3

) o

r b

oss

(Fi

g. 4

) o

r w

eld

ing

n

eck

(Fig

. 6)

(exc

ept

for

valv

es)

Forg

ed

or

cast

st

eel

inte

gra

l (F

ig. 5

) (f

or

va

lves

o

nly

)

HD

PN

OA

BE

CG

JK

LM

T 1T 3

T 5T 6

T 9in

inin

inin

inin

inin

inin

inin

inin

inin

inin

in1 ⁄2

27⁄32

3 3 ⁄4

2 5 ⁄8

41 ⁄2

3 ⁄81

5 ⁄16

1 1 ⁄2

——

1 1 ⁄1

67 ⁄8

7⁄8

5⁄8

1⁄2

1⁄4

3 ⁄16

E) 3⁄8

E) 3⁄8

3 ⁄41

1 ⁄16

42

7 ⁄84

1 ⁄27 ⁄1

61

1 ⁄21

3 ⁄4—

—1

5 ⁄16

1 3 ⁄3

2 7⁄8

5⁄8

1⁄2

1⁄4

3 ⁄16

E) 3⁄8

E) 3⁄8

11

11⁄32

4 1 ⁄2

3 1 ⁄4

41 ⁄2

7 ⁄16

1 7 ⁄8

2 1 ⁄1

6—

—1

11⁄16

1 3 ⁄8

7⁄8

5⁄8

1⁄2

5⁄16

3 ⁄16

E) 3⁄8

E) 3⁄8

1 1 ⁄4

1 11

⁄164

3 ⁄43

7 ⁄16

41 ⁄2

7 ⁄16

2 3 ⁄1

62

9 ⁄32

——

1 15

⁄161

23⁄32

1 5⁄8

5⁄8

5⁄16

1 ⁄4 E)

1⁄2

1⁄2

1 1 ⁄2

1 29

⁄325

1 ⁄43

7 ⁄84

1 ⁄21 ⁄2

2 7 ⁄1

62

3 ⁄4—

—2

5 ⁄16

1 15

⁄161

1 ⁄8 3⁄4

5⁄8

3⁄8

1 ⁄4 E)

1⁄2

1⁄2

22

3 ⁄86

4 1 ⁄2

45 ⁄8

1 ⁄22

15⁄16

3 1 ⁄8

——

2 3 ⁄4

2 13

⁄321

1 ⁄8 3⁄4

11 ⁄1

6 3⁄8

5 ⁄16

E) 9⁄16

9⁄16

2 1 ⁄2

36

1 ⁄25

45 ⁄8

5 ⁄83

9 ⁄16

3 21

⁄32—

—3

1 ⁄43

1 ⁄32

1 1 ⁄4

7⁄8

11 ⁄1

6 7⁄16

5 ⁄16

E) 9⁄16

9⁄16

33

1 ⁄27

1 ⁄45

3 ⁄44

5 ⁄85 ⁄8

4 3 ⁄1

64

13⁄32

——

43

17⁄32

1 3 ⁄8

1 3⁄4

1⁄2

3 ⁄8 E)

9⁄16

9⁄16

3 1 ⁄2

48

6 1 ⁄2

45 ⁄8

11⁄16

4 11

⁄165

1 ⁄8—

—4

1 ⁄24

1 ⁄16

1 3 ⁄8

1 3⁄4

9⁄16

3 ⁄8 E)

9⁄16

9⁄16

44

1 ⁄28

1 ⁄27

45 ⁄8

3 ⁄45

1 ⁄45

1 ⁄2—

—5

1 ⁄84

9 ⁄16

1 5 ⁄8

1 1 ⁄4

3⁄4

5⁄8

3 ⁄8 E)

11 ⁄1

6 1

1 ⁄16

55

1 ⁄210

8 1 ⁄4

85 ⁄8

3 ⁄46

5 ⁄16

6 3 ⁄4

——

65

9 ⁄16

1 3 ⁄4

1 1 ⁄4

13 ⁄1

6 1

1 ⁄16

1 ⁄2 1

1 ⁄16

11 ⁄1

6

66

1 ⁄211

9 1 ⁄4

85 ⁄8

3 ⁄47

5 ⁄16

7 3 ⁄4

——

7 1 ⁄4

6 9 ⁄1

61

7 ⁄81

1 ⁄4 1

3 ⁄16

11 ⁄1

61 ⁄2

11 ⁄1

6 1

1 ⁄16

6 5 ⁄8

6 23

⁄32

77

5 ⁄812

10 1 ⁄4

85 ⁄8

7 ⁄88

3 ⁄48

3 ⁄4—

—8

1 ⁄47

23⁄32

21

3 ⁄8 7⁄8

3⁄4

1 ⁄2 3⁄4

3⁄4

88

5 ⁄813

1 ⁄411

1 ⁄28

5 ⁄87 ⁄8

9 1 ⁄2

10—

—9

1 ⁄28

23⁄32

21

3 ⁄8 7⁄8

3⁄4

1 ⁄2 3⁄4

3⁄4

99

5 ⁄814

1 ⁄212

3 ⁄48

5 ⁄81

10 1 ⁄2

11 1 ⁄8

——

10 5 ⁄8

9 3 ⁄4

2 1 ⁄4

1 1 ⁄2

7⁄8

3⁄4

5 ⁄8 3⁄4

3⁄4

1010

3 ⁄416

148

3 ⁄41

1 ⁄16

11 3 ⁄4

12 3 ⁄1

6—

—11

1 ⁄210

7 ⁄82

1 ⁄21

3 ⁄41

3⁄4

5 ⁄8 3⁄4

3⁄4

1212

3 ⁄418

1612

3 ⁄41

1 ⁄813

3 ⁄414

3 ⁄16

——

13 1 ⁄2

12 29

⁄322

3 ⁄42

1 7⁄8

3 ⁄4 7⁄8

7⁄8

1314

19 1 ⁄4

17 1 ⁄4

123 ⁄4

——

——

—15

14 5 ⁄3

22

7 ⁄82

1 ⁄81

7⁄8

3 ⁄4 7⁄8

7⁄8

1415

F)20

3 ⁄418

1 ⁄212

7 ⁄8—

——

——

1615

5 ⁄32

2 7 ⁄8

2 1 ⁄8

1 1 ⁄8

17 ⁄8

11

1516

21 3 ⁄4

19 1 ⁄2

127 ⁄8

——

——

—17

16 3 ⁄1

63

2 1 ⁄4

1 1 ⁄8

17 ⁄8

11

Page 16

BS 10:2009

10 • © BSI 2009

BRITISH STANDARD BRITISH STANDARD

© BSI 2009 • 11

BS 10:2009Ta

ble

D

Dim

ensi

on

s o

f p

lain

, bo

ss, i

nte

gra

lly c

ast

or

forg

ed a

nd

wel

din

g n

eck

flan

ges

(fo

r ra

tin

gs

see

Tab

le 2

an

d A

nn

ex B

) (c

on

tin

ued

)

Flan

ge

size

des

-ig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

x-im

ate

ou

tsid

e d

iam

-et

er o

f st

eel

pip

e A

)

Dia

m-

eter

of

flan

ge

Bo

lt

circ

le

dia

m-

eter

No

. o

f b

olt

s

Dia

m-

eter

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(F

ig 4

) C

)D

imen

sio

ns

of

nec

ks f

or

cast

ir

on

(Fi

g. 7

)

Dim

ensi

on

s o

f st

eel w

eld

ing

n

ecks

(Fi

g. 6

)Th

ickn

ess

of

flan

ge

Bo

ss

len

gth

Dia

m-

eter

at

smal

l en

d

of

bo

ss

Max

i-m

um

d

iam

-et

er a

t ro

ot

of

bo

ss

Dia

m-

eter

at

larg

e en

d

of

nec

k

Len

gth

o

f ta

per

Dia

m-

eter

at

larg

e en

d

of

nec

k

Dia

m-

eter

at

smal

l en

d o

f n

eck

D)

Tota

l le

ng

th

of

nec

k

Len

gth

o

f ta

per

Gre

y ca

st ir

on

in

te-

gra

lly

cast

or

scre

wed

o

n w

ith

b

oss

Co

pp

er

allo

y ca

st o

r w

rou

gh

t in

teg

ral

or

bo

ss

or

pla

in

(Fig

. 3)

Wro

ug

ht

stee

l in

teg

ral

or

pla

in

(Fig

. 3)

or

bo

ss

(Fig

. 4)

or

wel

din

g

nec

k (F

ig. 6

) (e

xcep

t fo

r va

lves

)

Cas

t st

eel

inte

gra

l o

r p

lain

(F

ig. 3

) o

r b

oss

(Fi

g. 4

) o

r w

eld

ing

n

eck

(Fig

. 6)

(exc

ept

for

valv

es)

Forg

ed

or

cast

st

eel

inte

gra

l (F

ig. 5

) (f

or

va

lves

o

nly

)

HD

PN

OA

BE

CG

JK

LM

T 1T 3

T 5T 6

T 9in

inin

inin

inin

inin

inin

inin

inin

inin

inin

in

16—

22 3 ⁄4

20 1 ⁄2

12 7⁄8

——

——

——

——

—1

1 ⁄81

7⁄8

11

1718

2421

3 ⁄412

7⁄8

——

——

——

——

—1

1 ⁄81

1 ⁄81

1 1 ⁄8

1 1 ⁄8

18—

25 1 ⁄4

2312

7⁄8

——

——

——

——

—1

1 ⁄41

1 ⁄81

1 1 ⁄8

1 1 ⁄8

1920

26 1 ⁄2

2412

7⁄8

——

——

——

——

—1

1 ⁄41

1 ⁄81

1 1 ⁄8

1 1 ⁄8

20—

27 3 ⁄4

25 1 ⁄4

16 7⁄8

——

——

——

——

—1

1 ⁄41

1 ⁄41

1 ⁄81

1 ⁄41

1 ⁄4

2122

2926

1 ⁄216

7⁄8

——

——

——

——

—1

3 ⁄81

1 ⁄41

1 ⁄81

1 ⁄41

1 ⁄4

22—

3027

1 ⁄216

1—

——

——

——

——

1 3 ⁄8

1 1 ⁄4

1 1 ⁄8

1 1 ⁄4

1 1 ⁄4

2324

3128

1 ⁄216

1—

——

——

——

——

1 3 ⁄8

1 3 ⁄8

1 1 ⁄8

1 3 ⁄8

1 3 ⁄8

24—

32 1 ⁄2

29 3 ⁄4

161

——

——

——

——

—1

3 ⁄81

3 ⁄81

1 ⁄41

3 ⁄81

3 ⁄8

2728

35 3 ⁄4

33 1 ⁄4

201

——

——

——

——

—1

1 ⁄2—

1 3 ⁄8

1 1 ⁄2

1 1 ⁄2

2930

38 1 ⁄4

35 1 ⁄2

201

1 ⁄8—

——

——

——

——

1 1 ⁄2

—1

5 ⁄81

5 ⁄81

1 ⁄2

30—

39 1 ⁄4

36 1 ⁄2

201

1 ⁄8—

——

——

——

——

1 5 ⁄8

—1

5 ⁄81

5 ⁄81

5 ⁄8

3334

4340

201

1 ⁄4—

——

——

——

——

1 5 ⁄8

—1

3 ⁄41

3 ⁄41

5 ⁄8

3536

4542

241

1 ⁄4—

——

——

——

——

1 3 ⁄4

—1

7 ⁄81

7 ⁄81

3 ⁄4

36—

46 1 ⁄4

4324

1 1 ⁄4

——

——

——

——

—1

3 ⁄4—

1 7 ⁄8

1 7 ⁄8

1 3 ⁄4

3940

49 1 ⁄2

46 1 ⁄4

241

1 ⁄4—

——

——

——

——

1 3 ⁄4

—2

21

3 ⁄4

4243

52 1 ⁄2

49 1 ⁄4

281

1 ⁄4—

——

——

——

——

1 7 ⁄8

—2

1 ⁄82

1 ⁄81

7 ⁄8

45—

55 3 ⁄4

52 1 ⁄2

281

1 ⁄4—

——

——

——

——

2—

2 1 ⁄4

2 1 ⁄4

2

4849

58 3 ⁄4

55 1 ⁄2

321

1 ⁄4—

——

——

——

——

2—

2 3 ⁄8

2 3 ⁄8

2

5455

63 1 ⁄4

60 1 ⁄4

361

1 ⁄4—

——

——

——

——

2 1 ⁄4

—2

3 ⁄82

3 ⁄82

1 ⁄4

6061

70 1 ⁄4

6740

1 3 ⁄8

——

——

——

——

—2

3 ⁄8—

2 1 ⁄2

2 1 ⁄2

2 3 ⁄8

Page 17

BS 10:2009

10 • © BSI 2009

BRITISH STANDARD BRITISH STANDARD

© BSI 2009 • 11

BS 10:2009

Tab

le D

D

imen

sio

ns

of

pla

in, b

oss

, in

teg

rally

cas

t o

r fo

rged

an

d w

eld

ing

nec

k fl

ang

es (

for

rati

ng

s se

e Ta

ble

2 a

nd

An

nex

B)

(co

nti

nu

ed)

Flan

ge

size

des

-ig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

x-im

ate

ou

tsid

e d

iam

-et

er o

f st

eel

pip

e A

)

Dia

m-

eter

of

flan

ge

Bo

lt

circ

le

dia

m-

eter

No

. o

f b

olt

s

Dia

m-

eter

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(F

ig 4

) C

)D

imen

sio

ns

of

nec

ks f

or

cast

ir

on

(Fi

g. 7

)

Dim

ensi

on

s o

f st

eel w

eld

ing

n

ecks

(Fi

g. 6

)Th

ickn

ess

of

flan

ge

Bo

ss

len

gth

Dia

m-

eter

at

smal

l en

d

of

bo

ss

Max

i-m

um

d

iam

-et

er a

t ro

ot

of

bo

ss

Dia

m-

eter

at

larg

e en

d

of

nec

k

Len

gth

o

f ta

per

Dia

m-

eter

at

larg

e en

d

of

nec

k

Dia

m-

eter

at

smal

l en

d o

f n

eck

D)

Tota

l le

ng

th

of

nec

k

Len

gth

o

f ta

per

Gre

y ca

st ir

on

in

te-

gra

lly

cast

or

scre

wed

o

n w

ith

b

oss

Co

pp

er

allo

y ca

st o

r w

rou

gh

t in

teg

ral

or

bo

ss

or

pla

in

(Fig

. 3)

Wro

ug

ht

stee

l in

teg

ral

or

pla

in

(Fig

. 3)

or

bo

ss

(Fig

. 4)

or

wel

din

g

nec

k (F

ig. 6

) (e

xcep

t fo

r va

lves

)

Cas

t st

eel

inte

gra

l o

r p

lain

(F

ig. 3

) o

r b

oss

(Fi

g. 4

) o

r w

eld

ing

n

eck

(Fig

. 6)

(exc

ept

for

valv

es)

Forg

ed

or

cast

st

eel

inte

gra

l (F

ig. 5

) (f

or

va

lves

o

nly

)

HD

PN

OA

BE

CG

JK

LM

T 1T 3

T 5T 6

T 9in

inin

inin

inin

inin

inin

inin

inin

inin

inin

in

6667

1 ⁄476

1 ⁄273

1 ⁄440

1 3 ⁄8

——

——

——

——

—2

1 ⁄2—

2 5 ⁄8

2 5 ⁄8

2 1 ⁄2

7273

1 ⁄483

79 1 ⁄2

441

1 ⁄2—

——

——

——

——

2 5 ⁄8

—2

7 ⁄82

7 ⁄82

5 ⁄8

78—

89 1 ⁄2

8644

1 1 ⁄2

——

—82

2 7 ⁄8

——

——

2 3 ⁄4

—3

——

84—

96 3 ⁄4

92 3 ⁄4

441

3 ⁄4—

——

88 1 ⁄4

2 7 ⁄8

——

——

2 7 ⁄8

—3

1 ⁄4—

—

96—

109

1 ⁄410

5 1 ⁄4

521

3 ⁄4—

——

100

3 ⁄43

1 ⁄2—

——

—3

1 ⁄4—

3 5 ⁄8

——

108

—12

1 3 ⁄4

117

3 ⁄456

1 3 ⁄4

——

—11

3 1 ⁄4

4 1 ⁄4

——

——

3 1 ⁄2

—4

——

120

—13

513

0 1 ⁄2

602

——

—12

5 1 ⁄2

4 1 ⁄4

——

——

3 3 ⁄4

—4

1 ⁄2—

—A

) (H

) Fo

r av

aila

bili

ty o

f st

eel p

ipe

size

s, r

efer

to

BS

EN 1

0216

, BS

EN 1

0217

. See

BS

4622

an

d B

S 47

22 f

or

ou

tsid

e d

iam

eter

s o

f ca

st ir

on

pip

es. S

ee B

S EN

124

49 f

or

the

size

s o

f co

pp

er p

ipes

fo

r u

se w

ith

co

pp

er a

lloy

flan

ges

up

to

8 in

bo

re.

B)

(O)

For

1 ⁄2 in

an

d 5 ⁄8

in b

olt

s, t

he

dia

met

ers

of

the

ho

les

shal

l be

1 ⁄16

in la

rger

th

an t

he

bo

lts

and

fo

r 3 ⁄4

in b

olt

s an

d s

izes

ab

ove

, th

e d

iam

eter

s sh

all b

e n

ot

mo

re t

han

1 ⁄8 in

larg

er t

han

th

e b

olt

s. F

or

cast

iro

n fl

ang

es t

he

dia

met

ers

of

the

bo

lt h

ole

s m

ay b

e 1 ⁄8

in la

rger

th

an t

he

bo

lts

of

size

s 5 ⁄8

in a

nd

ab

ove

.Fo

r 7 ⁄8

in b

olt

s an

d s

izes

ab

ove

, th

e d

iam

eter

s sh

all b

e n

ot

mo

re t

han

1 ⁄8 in

larg

er t

han

th

e b

olt

s.C

) (A

. B &

E)

Tap

ers

are

no

t sp

ecifi

ed b

ut

shal

l be

such

th

at t

he

max

imu

m d

iam

eter

s at

ro

ot

of

bo

ss a

re n

ot

exce

eded

.D

) (K

) Th

e d

iam

eter

s ta

bu

late

d a

pp

ly t

o p

ipes

wit

h o

uts

ide

dia

met

ers

in a

cco

rdan

ce w

ith

H. F

or

pip

es d

esig

nat

ed b

y th

eir

bo

res,

dim

ensi

on

K s

hal

l be

such

th

at t

he

dif

fere

nce

bet

wee

n t

he

corr

esp

on

din

g d

iam

eter

s K

an

d H

is m

ain

tain

ed.

E)

(T5

and

T6)

It is

imp

ract

icab

le t

o u

se t

hic

knes

s le

ss t

han

1 ⁄2 in

exc

ept

for

bo

ss a

nd

inte

gra

l flan

ges

.F)

(H

) It

is r

eco

mm

end

ed t

hat

th

is s

ize

for

stee

l pip

es s

ho

uld

be

avo

ided

wh

erev

er p

oss

ible

.

Page 18

BS 10:2009

12 • © BSI 2009

BRITISH STANDARD BRITISH STANDARD

© BSI 2009 • 13

BS 10:2009Ta

ble

E

Dim

ensi

on

s o

f p

lain

, bo

ss, i

nte

gra

lly c

ast

or

forg

ed, a

nd

wel

din

g n

eck

flan

ges

(fo

r ra

tin

gs

see

Tab

le 2

an

d A

nn

ex B

)

Flan

ge

size

des

-ig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

xi-

mat

e o

uts

ide

dia

met

er

of

stee

l p

ipe

A)

Dia

m-

eter

of

flan

ge

Bo

lt

circ

le

dia

m-

eter

No

. of

bo

lts

Dia

m-

eter

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(F

ig.4

) C

)D

imen

sio

ns

of

stee

l wel

din

g n

ecks

(F

ig. 6

)Th

ickn

ess

of

flan

ge

Bo

ss

len

gth

Dia

m-

eter

at

smal

l en

d o

f b

oss

Max

i-m

um

d

iam

-et

er a

t ro

ot

of

bo

ss

Dia

m-

eter

at

larg

e en

d o

f n

eck

D)

Dia

m-

eter

at

smal

l en

d o

f n

eck

Tota

l le

ng

th

of

nec

k

Len

gth

o

f ta

per

Gre

y ca

st ir

on

in

teg

rally

ca

st o

r sc

rew

ed

on

wit

h

bo

ss

Co

pp

er

allo

y ca

st o

r w

rou

gh

t in

teg

ral

or

bo

ss

or

pla

in

(Fig

. 3)

Wro

ug

ht

stee

l in

te-

gra

l or

pla

in

(Fig

. 3)

or

bo

ss (

Fig

. 4)

or

wel

din

g

nec

k (F

ig. 6

) (e

xcep

t fo

r va

lves

)

Cas

t st

eel

inte

gra

l o

r p

lain

(F

ig. 3

) o

r b

oss

(Fi

g. 4

) o

r w

eld

ing

n

eck

(Fig

. 6)

(exc

ept

for

valv

es)

Forg

ed o

r ca

st s

teel

in

teg

ral

(Fig

. 5)

(fo

r va

lves

o

nly

)

HD

PN

OA

BE

JK

LM

T 1T 3

T 5T 6

T 9in

inin

inin

inin

inin

inin

inin

inin

inin

1⁄2

27 ⁄3

23

3 ⁄42

5 ⁄84

1 ⁄2 3⁄8

1 5 ⁄1

61

1 ⁄21

1 ⁄16

7 ⁄8 7⁄8

5⁄8

1⁄2

1⁄4

1⁄4

E) 3⁄8

E) 3⁄8

3⁄4

1 1 ⁄1

64

2 7 ⁄8

41 ⁄2

7⁄16

1 1 ⁄2

1 3 ⁄4

1 5 ⁄1

61

3 ⁄32

7⁄8

5⁄8

1⁄2

1⁄4

1⁄4

E) 3⁄8

E) 3⁄8

11

11⁄32

4 1 ⁄2

3 1 ⁄4

41 ⁄2

7⁄16

1 7 ⁄8

2 1 ⁄1

61

11⁄16

1 3 ⁄8

7⁄8

5⁄8

1⁄2

5⁄16

9⁄32

E) 3⁄8

E) 3⁄8

1 1 ⁄4

1 11

⁄164

3 ⁄43

7 ⁄16

41 ⁄2

7⁄16

2 3 ⁄1

62

9 ⁄32

1 15

⁄161

23⁄32

1 5⁄8

5⁄8

5⁄16

5⁄16

E) 1⁄2

1⁄2

1 1 ⁄2

1 29

⁄325

1 ⁄43

7 ⁄84

1 ⁄2 1⁄2

2 7 ⁄1

62

3 ⁄42

5 ⁄16

1 15

⁄161

1 ⁄8 3⁄4

5⁄8

3⁄8

11 ⁄3

2 E)

1⁄2

1⁄2

22

3 ⁄86

4 1 ⁄2

45 ⁄8

1⁄2

2 15

⁄163

1 ⁄82

3 ⁄42

13⁄32

1 1 ⁄8

3⁄4

3⁄4

3⁄8

3⁄8

E) 9⁄16

9⁄16

2 1 ⁄2

36

1 ⁄25

45 ⁄8

5⁄8

3 9 ⁄1

63

21⁄32

3 1 ⁄4

3 1 ⁄3

21

1 ⁄4 7⁄8

3⁄4

7⁄16

13 ⁄3

2 E)

9⁄16

9⁄16

33

1 ⁄27

1 ⁄45

3 ⁄44

5 ⁄8 5⁄8

4 3 ⁄1

64

13⁄32

43

17⁄32

1 3 ⁄8

1 3⁄4

1⁄2

7⁄16

E) 9⁄16

9⁄16

3 1 ⁄2

48

6 1 ⁄2

85 ⁄8

11 ⁄1

64

11⁄16

5 1 ⁄8

4 1 ⁄2

4 1 ⁄1

61

3 ⁄81

3⁄4

9⁄16

15 ⁄3

2 E)

9⁄16

9⁄16

44

1 ⁄28

1 ⁄27

1 ⁄48

5 ⁄8 3⁄4

5 1 ⁄4

5 1 ⁄2

5 1 ⁄8

4 9 ⁄1

61

5 ⁄81

1 ⁄4 7⁄8

5⁄8

1⁄2

11 ⁄1

6 1

1 ⁄16

55

1 ⁄210

8 1 ⁄4

85 ⁄8

3⁄4

6 5 ⁄1

66

3 ⁄46

5 9 ⁄1

61

3 ⁄41

1 ⁄4 7⁄8

11 ⁄1

6 9⁄16

11 ⁄1

6 1

1 ⁄16

66

1 ⁄211

9 1 ⁄4

83 ⁄4

3⁄4

7 5 ⁄1

67

1 ⁄27

1 ⁄46

9 ⁄16

1 7 ⁄8

1 1 ⁄4

7⁄8

11 ⁄1

6 1

1 ⁄16

11 ⁄1

6 1

1 ⁄16

6 5 ⁄8

6 23

⁄32

77

5 ⁄812

10 1 ⁄4

83 ⁄4

7⁄8

8 3 ⁄8

8 1 ⁄2

8 1 ⁄4

7 23

⁄322

1 3 ⁄8

1 3⁄4

3⁄4

3⁄4

3⁄4

88

5 ⁄813

1 ⁄411

1 ⁄28

3 ⁄4 7⁄8

9 1 ⁄2

9 13

⁄169

1 ⁄28

23⁄32

21

3 ⁄81

3⁄4

3⁄4

3⁄4

3⁄4

99

5 ⁄814

1 ⁄212

3 ⁄412

3 ⁄41

10 1 ⁄2

10 15

⁄1610

5 ⁄89

3 ⁄42

1 ⁄41

1 ⁄21

13 ⁄1

6 1

3 ⁄16

13 ⁄1

6 1

3 ⁄16

1010

3 ⁄416

1412

3 ⁄41

1 ⁄16

11 3 ⁄4

12 3 ⁄1

611

1 ⁄210

7 ⁄82

1 ⁄21

3 ⁄41

7⁄8

7⁄8

7⁄8

7⁄8

1212

3 ⁄418

1612

7 ⁄81

1 ⁄813

3 ⁄413

15⁄16

13 1 ⁄2

12 29

⁄322

3 ⁄42

1 1 ⁄8

11

11

1314

19 1 ⁄4

17 1 ⁄4

127 ⁄8

——

—15

14 5 ⁄3

22

7 ⁄82

1 ⁄81

1 ⁄81

11

1

1415

F)20

3 ⁄418

1 ⁄212

7 ⁄8—

——

1615

5 ⁄32

2 7 ⁄8

2 1 ⁄8

1 1 ⁄4

11

1 ⁄81

1 ⁄81

1516

21 3 ⁄4

19 1 ⁄2

127 ⁄8

——

—17

16 3 ⁄1

63

2 1 ⁄4

1 1 ⁄4

11

1 ⁄41

1 ⁄41

16—

22 3 ⁄4

20 1 ⁄2

127 ⁄8

——

——

——

—1

1 ⁄41

1 1 ⁄4

1 1 ⁄4

1

1718

2421

3 ⁄412

7 ⁄8—

——

——

——

1 3 ⁄8

1 1 ⁄8

1 3 ⁄8

1 3 ⁄8

1 1 ⁄8

18—

25 1 ⁄4

2316

7 ⁄8—

——

——

——

1 3 ⁄8

1 1 ⁄8

1 3 ⁄8

1 3 ⁄8

1 1 ⁄8

Page 19

BS 10:2009

12 • © BSI 2009

BRITISH STANDARD BRITISH STANDARD

© BSI 2009 • 13

BS 10:2009

Tab

le E

D

imen

sio

ns

of

pla

in, b

oss

, in

teg

rally

cas

t o

r fo

rged

, an

d w

eld

ing

nec

k fl

ang

es (

for

rati

ng

s se

e Ta

ble

2 a

nd

An

nex

B)

(co

nti

nu

ed)

Flan

ge

size

des

-ig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

xi-

mat

e o

uts

ide

dia

met

er

of

stee

l p

ipe

A)

Dia

m-

eter

of

flan

ge

Bo

lt

circ

le

dia

m-

eter

No

. of

bo

lts

Dia

m-

eter

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(F

ig.4

) C

)D

imen

sio

ns

of

stee

l wel

din

g n

ecks

(F

ig. 6

)Th

ickn

ess

of

flan

ge

Bo

ss

len

gth

Dia

m-

eter

at

smal

l en

d o

f b

oss

Max

i-m

um

d

iam

-et

er a

t ro

ot

of

bo

ss

Dia

m-

eter

at

larg

e en

d o

f n

eck

D)

Dia

m-

eter

at

smal

l en

d o

f n

eck

Tota

l le

ng

th

of

nec

k

Len

gth

o

f ta

per

Gre

y ca

st ir

on

in

teg

rally

ca

st o

r sc

rew

ed

on

wit

h

bo

ss

Co

pp

er

allo

y ca

st o

r w

rou

gh

t in

teg

ral

or

bo

ss

or

pla

in

(Fig

. 3)

Wro

ug

ht

stee

l in

te-

gra

l or

pla

in

(Fig

. 3)

or

bo

ss (

Fig

. 4)

or

wel

din

g

nec

k (F

ig. 6

) (e

xcep

t fo

r va

lves

)

Cas

t st

eel

inte

gra

l o

r p

lain

(F

ig. 3

) o

r b

oss

(Fi

g. 4

) o

r w

eld

ing

n

eck

(Fig

. 6)

(exc

ept

for

valv

es)

Forg

ed o

r ca

st s

teel

in

teg

ral

(Fig

. 5)

(fo

r va

lves

o

nly

)

HD

PN

OA

BE

JK

LM

T 1T 3

T 5T 6

T 9in

inin

inin

inin

inin

inin

inin

inin

inin

1920

26 1 ⁄2

2416

7⁄8

——

——

——

—1

3 ⁄81

1 ⁄41

1 ⁄21

1 ⁄21

1 ⁄4

20—

27 3 ⁄4

25 1 ⁄4

16 7⁄8

——

——

——

—1

1 ⁄21

1 ⁄41

1 ⁄21

1 ⁄21

1 ⁄4

2122

2926

1 ⁄216

1—

——

——

——

1 1 ⁄2

1 3 ⁄8

1 5 ⁄8

1 5 ⁄8

1 3 ⁄8

22—

3027

1 ⁄216

1—

——

——

——

1 1 ⁄2

1 3 ⁄8

1 3 ⁄4

1 3 ⁄4

1 3 ⁄8

2324

3128

1 ⁄216

1—

——

——

——

1 5 ⁄8

1 3 ⁄8

1 3 ⁄4

1 3 ⁄4

1 3 ⁄8

24—

32 1 ⁄2

29 3 ⁄4

161

1 ⁄8—

——

——

——

1 5 ⁄8

1 1 ⁄2

1 7 ⁄8

1 7 ⁄8

1 1 ⁄2

2728

35 3 ⁄4

33 1 ⁄4

201

1 ⁄8—

——

——

——

1 3 ⁄4

—2

21

3 ⁄4

2930

38 1 ⁄4

35 1 ⁄2

201

1 ⁄4—

——

——

——

1 7 ⁄8

—2

1 ⁄82

1 ⁄81

7 ⁄8

30—

39 1 ⁄4

36 1 ⁄2

201

1 ⁄4—

——

——

——

1 7 ⁄8

—2

1 ⁄82

1 ⁄81

7 ⁄8

3334

4340

201

1 ⁄4—

——

——

——

2—

2 1 ⁄4

2 1 ⁄4

2

3536

4542

241

1 ⁄4—

——

——

——

2—

2 1 ⁄2

2 1 ⁄2

2

36—

46 1 ⁄4

4324

1 1 ⁄4

——

——

——

—2

—2

1 ⁄22

1 ⁄22

3940

49 1 ⁄2

46 1 ⁄4

241

3 ⁄8—

——

——

——

2 1 ⁄8

—2

5 ⁄82

5 ⁄82

1 ⁄8

4243

52 1 ⁄2

49 1 ⁄4

281

3 ⁄8—

——

——

——

2 1 ⁄4

—2

3 ⁄42

3 ⁄42

1 ⁄4

45—

55 3 ⁄4

52 1 ⁄2

281

3 ⁄8—

——

——

——

2 3 ⁄8

—3

32

3 ⁄8

4849

58 3 ⁄4

55 1 ⁄2

321

3 ⁄8—

——

——

——

2 3 ⁄8

—3

1 ⁄83

1 ⁄82

3 ⁄8A

) (H

) Fo

r av

aila

bili

ty o

f st

eel p

ipe

size

s, r

efer

to

BS

EN 1

0216

, BS

EN 1

0217

. See

BS

4622

an

d B

S 47

22 f

or

ou

tsid

e d

iam

eter

s o

f ca

st ir

on

pip

es. S

ee B

S EN

124

49 f

or

the

size

s o

f co

pp

er p

ipes

fo

r u

se w

ith

co

pp

er a

lloy

flan

ges

up

to

8 in

bo

re.

B)

(O)

For

1 ⁄2 in

an

d 5 ⁄8

in b

olt

s, t

he

dia

met

ers

of

the

ho

les

shal

l be

1 ⁄16

in la

rger

th

an t

he

bo

lts

and

fo

r 3 ⁄4

in b

olt

s an

d s

izes

ab

ove

, th

e d

iam

eter

s sh

all b

e n

ot

mo

re t

han

1 ⁄8 in

larg

er t

han

th

e b

olt

s.

For

cast

iro

n fl

ang

es t

he

dia

met

ers

of

the

bo

lt h

ole

s m

ay b

e 1 ⁄8

in la

rger

th

an t

he

bo

lts

of

size

s 5 ⁄8

in a

nd

ab

ove

.Fo

r 7 ⁄8

in b

olt

s an

d s

izes

ab

ove

, th

e d

iam

eter

s sh

all b

e n

ot

mo

re t

han

1 ⁄8 in

larg

er t

han

th

e b

olt

s.C

) (A

. B &

E)

Tap

ers

are

no

t sp

ecifi

ed b

ut

shal

l be

such

th

at t

he

max

imu

m d

iam

eter

s at

ro

ot

of

bo

ss a

re n

ot

exce

eded

.D

) (K

) Th

e d

iam

eter

s ta

bu

late

d a

pp

ly t

o p

ipes

wit

h o

uts

ide

dia

met

ers

in a

cco

rdan

ce w

ith

H. F

or

pip

es d

esig

nat

ed b

y th

eir

bo

res,

dim

ensi

on

K s

hal

l be

such

th

at t

he

dif

fere

nce

bet

wee

n t

he

corr

esp

on

din

g d

iam

eter

s K

an

d H

is m

ain

tain

ed.

E)

(T5

and

T6)

It is

imp

ract

icab

le t

o u

se t

hic

knes

s le

ss t

han

1 ⁄2 in

exc

ept

for

bo

ss a

nd

inte

gra

l flan

ges

.F)

(H

) It

is r

eco

mm

end

ed t

hat

th

is s

ize

for

stee

l pip

es s

ho

uld

be

avo

ided

wh

erev

er p

oss

ible

.

Page 20

BS 10:2009

14 • © BSI 2009

BRITISH STANDARD BRITISH STANDARD

© BSI 2009 • 15

BS 10:2009Ta

ble

F

Dim

ensi

on

s o

f p

lain

, bo

ss, i

nte

gra

lly c

ast

or

forg

ed, a

nd

wel

din

g n

eck

flan

ges

(fo

r ra

tin

gs

see

Tab

le 2

an

d A

nn

ex B

)

Flan

ge

size

des

-ig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

xi-

mat

e o

uts

ide

dia

met

er

of

stee

l p

ipe

A)

Dia

m-

eter

of

flan

ge

Bo

lt

circ

le

dia

m-

eter

No

. o

f b

olt

s

Dia

m-

eter

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(F

ig. 4

) C

)D

imen

sio

ns

of

nec

ks f

or

cast

ir

on

(Fi

g. 7

)

Dim

ensi

on

s o

f st

eel w

eld

ing

nec

ks

(Fig

. 6)

Thic

knes

s o

f fl

ang

e

Bo

ss

len

gth

Dia

m-

eter

at

smal

l en

d o

f b

oss

Max

i-m

um

d

iam

-et

er a

t ro

ot

of

bo

ss

Dia

m-

eter

at

larg

e en

d o

f n

eck

Len

gth

o

f ta

per

Dia

m-

eter

at

larg

e en

d o

f n

eck

Dia

m-

eter

at

smal

l en

d o

f n

eck

D)

Tota

l le

ng

th

of

nec

k

Len

gth

o

f ta

per

Gre

y ca

st ir

on

in

teg

rally

ca

st o

r sc

rew

ed

on

wit

h

bo

ss

Co

pp

er

allo

y ca

st o

r w

rou

gh

t in

teg

ral

or

bo

ss

or

pla

in

(Fig

. 3)

Cas

t o

r w

rou

gh

t st

eel i

nte

-g

ral o

r p

lain

(F

ig. 3

) o

r b

oss

(Fi

g. 4

) o

r w

eld

ing

n

eck

(Fig

. 6)

(exc

ept

for

valv

es)

Forg

ed

or

cast

st

eel

inte

gra

l (F

ig. 5

) (f

or

valv

es

on

ly)

HD

PN

OA

BE

CG

JK

LM

T 1T 3

T 7T 9

inin

inin

inin

inin

inin

inin

inin

inin

inin

1⁄2

27 ⁄3

23

3 ⁄42

5 ⁄84

1⁄2

3⁄8

1 5 ⁄1

61

1 ⁄21

1⁄2

1 1 ⁄1

6 7⁄8

7⁄8

5⁄8

1⁄2

5⁄16

3⁄8

E) 3⁄8

3⁄4

1 1 ⁄1

64

2 7 ⁄8

4 1⁄2

7⁄16

1 1 ⁄2

1 3 ⁄4

1 1 ⁄4

1⁄2

1 5 ⁄1

61

3 ⁄32

7⁄8

5⁄8

1⁄2

5⁄16

3⁄8

E) 3⁄8

11

11⁄32

4 3 ⁄4

3 7 ⁄1

64

5⁄8

7⁄16

1 7 ⁄8

2 1 ⁄1

61

5 ⁄8 1⁄2

1 11

⁄161

3 ⁄81

1 ⁄8 5⁄8

1⁄2

3⁄8

3⁄8

E) 3⁄8

1 1 ⁄4

1 11

⁄165

1 ⁄43

7 ⁄84

5⁄8

7⁄16

2 3 ⁄1

62

1 ⁄22

5⁄8

2 1 ⁄1

61

23⁄32

1 3 ⁄8

3⁄4

5⁄8

3⁄8

1⁄2

1⁄2

1 1 ⁄2

1 29

⁄325

1 ⁄24

1 ⁄84

5⁄8

1⁄2

2 7 ⁄1

62

3 ⁄42

1 ⁄4 5⁄8

2 5 ⁄1

61

15⁄16

1 3 ⁄8

3⁄4

5⁄8

7⁄16

1⁄2

1⁄2

22

3 ⁄86

1 ⁄25

4 5⁄8

1⁄2

2 15

⁄163

21⁄32

3 3⁄4

2 3 ⁄4

2 13

⁄321

3 ⁄8 3⁄4

3⁄4

7⁄16

5⁄8

5⁄8

2 1 ⁄2

37

1 ⁄45

3 ⁄48

5⁄8

5⁄8

3 9 ⁄1

64

13⁄32

3 5 ⁄8

3⁄4

3 3 ⁄8

3 1 ⁄3

21

1 ⁄2 3⁄4

3⁄4

1⁄2

5⁄8

5⁄8

33

1 ⁄28

6 1 ⁄2

8 5⁄8

5⁄8

4 3 ⁄1

65

1 ⁄84

1 ⁄8 3⁄4

43

17⁄32

1 3 ⁄4

1 3⁄4

9⁄16

5⁄8

5⁄8

3 1 ⁄2

48

1 ⁄27

8 5⁄8

11 ⁄1

64

11⁄16

5 21

⁄324

3 ⁄4 7⁄8

4 1 ⁄2

4 1 ⁄1

61

3 ⁄41

7⁄8

5⁄8

3⁄4

3⁄4

44

1 ⁄29

7 1 ⁄2

8 5⁄8

3⁄4

5 1 ⁄4

65

1 ⁄4 7⁄8

5 1 ⁄8

4 9 ⁄1

62

1 1 ⁄4

7⁄8

11 ⁄1

6 3⁄4

3⁄4

55

1 ⁄211

9 1 ⁄4

8 3⁄4

3⁄4

6 5 ⁄1

67

1 ⁄26

1 ⁄21

6 1 ⁄4

5 9 ⁄1

62

1 ⁄41

1 ⁄21

3⁄4

7⁄8

7⁄8

66

1 ⁄212

10 1 ⁄4

12 3⁄4

3⁄4

7 5 ⁄1

68

1 ⁄27

5 ⁄81

7 1 ⁄4

6 9 ⁄1

62

1 ⁄41

1 ⁄21

7⁄8

7⁄8

7⁄8

6 5 ⁄8

6 23

⁄32

77

5 ⁄813

1 ⁄411

1 ⁄212

3⁄4

7⁄8

8 3 ⁄8

9 13

⁄168

5 ⁄81

8 3 ⁄8

7 23

⁄322

1 ⁄41

1 ⁄21

7⁄8

7⁄8

7⁄8

88

5 ⁄814

1 ⁄212

3 ⁄412

3⁄4

7⁄8

9 1 ⁄2

119

5 ⁄81

1 ⁄89

1 ⁄28

23⁄32

2 5 ⁄8

1 3 ⁄4

1 1 ⁄8

11

1

99

5 ⁄816

1412

7⁄8

110

1 ⁄211

15⁄16

10 3 ⁄4

1 1 ⁄8

10 5 ⁄8

9 3 ⁄4

2 7 ⁄8

21

1 ⁄81

1 1 ⁄8

1

1010

3 ⁄417

1512

7⁄8

1 1 ⁄1

611

3 ⁄412

15⁄16

11 3 ⁄4

1 1 ⁄8

11 3 ⁄4

10 7 ⁄8

2 7 ⁄8

21

1 ⁄81

1 1 ⁄8

1

1212

3 ⁄419

1 ⁄417

1 ⁄416

7⁄8

1 1 ⁄8

13 3 ⁄4

15 3 ⁄1

614

1 1 ⁄4

13 7 ⁄8

12 29

⁄323

1 ⁄82

1 ⁄41

1 ⁄41

1 ⁄81

1 ⁄41

1 ⁄8

1314

20 3 ⁄4

13 1 ⁄2

161

——

—15

1 ⁄81

1 ⁄415

1 ⁄414

5 ⁄32

3 3 ⁄8

2 1 ⁄2

1 1 ⁄4

1 1 ⁄8

1 3 ⁄8

1 1 ⁄8

1415

F)21

3 ⁄419

1 ⁄216

1—

——

16 1 ⁄8

1 3 ⁄8

16 1 ⁄4

15 5 ⁄3

23

3 ⁄82

1 ⁄21

3 ⁄81

1 ⁄41

3 ⁄81

1 ⁄4

1516

22 3 ⁄4

20 1 ⁄2

161

——

—17

1 ⁄41

3 ⁄817

1 ⁄416

3 ⁄16

3 3 ⁄8

2 1 ⁄2

1 3 ⁄8

1 1 ⁄4

1 1 ⁄2

1 1 ⁄4

16—

2421

3 ⁄420

1—

——

18 1 ⁄4

1 3 ⁄8

——

——

1 3 ⁄8

1 1 ⁄4

1 5 ⁄8

1 1 ⁄4

1718

25 1 ⁄4

2320

1—

——

19 3 ⁄8

1 1 ⁄2

——

——

1 1 ⁄2

1 3 ⁄8

1 3 ⁄4

1 3 ⁄8

18—

26 1 ⁄2

2420

1 1 ⁄8

——

—20

1 ⁄21

1 ⁄2—

——

—1

1 ⁄21

3 ⁄81

3 ⁄41

3 ⁄8

Page 21

BS 10:2009

14 • © BSI 2009

BRITISH STANDARD BRITISH STANDARD

© BSI 2009 • 15

BS 10:2009

Tab

le F

D

imen

sio

ns

of

pla

in, b

oss

, in

teg

rally

cas

t o

r fo

rged

, an

d w

eld

ing

nec

k fl

ang

es (

for

rati

ng

s se

e Ta

ble

2 a

nd

An

nex

B)

(co

nti

nu

ed)

Flan

ge

size

des

-ig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

xi-

mat

e o

uts

ide

dia

met

er

of

stee

l p

ipe

A)

Dia

m-

eter

of

flan

ge

Bo

lt

circ

le

dia

m-

eter

No

. o

f b

olt

s

Dia

m-

eter

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(F

ig. 4

) C

)D

imen

sio

ns

of

nec

ks f

or

cast

ir

on

(Fi

g. 7

)

Dim

ensi

on

s o

f st

eel w

eld

ing

nec

ks

(Fig

. 6)

Thic

knes

s o

f fl

ang

e

Bo

ss

len

gth

Dia

m-

eter

at

smal

l en

d o

f b

oss

Max

i-m

um

d

iam

-et

er a

t ro

ot

of

bo

ss

Dia

m-

eter

at

larg

e en

d o

f n

eck

Len

gth

o

f ta

per

Dia

m-

eter

at

larg

e en

d o

f n

eck

Dia

m-

eter

at

smal

l en

d o

f n

eck

D)

Tota

l le

ng

th

of

nec

k

Len

gth

o

f ta

per

Gre

y ca

st ir

on

in

teg

rally

ca

st o

r sc

rew

ed

on

wit

h

bo

ss

Co

pp

er

allo

y ca

st o

r w

rou

gh

t in

teg

ral

or

bo

ss

or

pla

in

(Fig

. 3)

Cas

t o

r w

rou

gh

t st

eel i

nte

-g

ral o

r p

lain

(F

ig. 3

) o

r b

oss

(Fi

g. 4

) o

r w

eld

ing

n

eck

(Fig

. 6)

(exc

ept

for

valv

es)

Forg

ed

or

cast

st

eel

inte

gra

l (F

ig. 5

) (f

or

valv

es

on

ly)

HD

PN

OA

BE

CG

JK

LM

T 1T 3

T 7T 9

inin

inin

inin

inin

inin

inin

inin

inin

inin

1920

27 3 ⁄4

25 1 ⁄4

201

1 ⁄8—

——

21 5 ⁄8

1 1 ⁄2

——

——

1 1 ⁄2

1 3 ⁄8

1 3 ⁄4

1 3 ⁄8

20—

2926

1 ⁄224

1 1 ⁄8

——

—22

3 ⁄41

5 ⁄8—

——

—1

5 ⁄81

1 ⁄22

1 1 ⁄2

2122

3027

1 ⁄224

1 1 ⁄8

——

—23

3 ⁄41

5 ⁄8—

——

—1

5 ⁄81

1 ⁄22

1 1 ⁄2

22—

3128

1 ⁄224

1 1 ⁄8

——

—24

3 ⁄41

5 ⁄8—

——

—1

5 ⁄81

1 ⁄22

1 ⁄81

1 ⁄2

2324

32 1 ⁄2

29 3 ⁄4

241

1 ⁄4—

——

25 7 ⁄8

1 3 ⁄4

——

——

1 3 ⁄4

1 5 ⁄8

2 1 ⁄4

1 5 ⁄8

24—

33 1 ⁄2

30 3 ⁄4

241

1 ⁄4—

——

271

3 ⁄4—

——

—1

3 ⁄41

5 ⁄82

1 ⁄41

5 ⁄8

2728

36 3 ⁄4

33 3 ⁄4

241

1 ⁄4—

——

30 1 ⁄4

1 7 ⁄8

——

——

1 7 ⁄8

—2

3 ⁄81

7 ⁄8

2930

3936

241

1 ⁄4—

——

32 1 ⁄2

2—

——

—2

—2

5 ⁄82

30—

4037

281

1 ⁄4—

——

33 1 ⁄2

2—

——

—2

—2

5 ⁄82

3334

4340

321

1 ⁄4—

——

36 1 ⁄2

2 1 ⁄8

——

——

2 1 ⁄8

—2

3 ⁄42

1 ⁄8

3536

45 3 ⁄4

42 1 ⁄2

321

3 ⁄8—

——

38 3 ⁄4

2 1 ⁄4

——

——

2 1 ⁄4

—3

2 1 ⁄4

36—

46 3 ⁄4

43 1 ⁄2

321

3 ⁄8—

——

39 3 ⁄4

2 1 ⁄4

——

——

2 1 ⁄4

—3

2 1 ⁄4

3940

50 1 ⁄4

4736

1 3 ⁄8

——

—43

2 3 ⁄8

——

——

2 3 ⁄8

—3

1 ⁄42

3 ⁄8

4243

53 1 ⁄4

5036

1 3 ⁄8

——

—46

2 1 ⁄2

——

——

2 1 ⁄2

—3

3 ⁄82

1 ⁄2

45—

5753

1 ⁄236

1 1 ⁄2

——

—49

1 ⁄42

5 ⁄8—

——

—2

5 ⁄8—

3 5 ⁄8

2 5 ⁄8

4849

60 1 ⁄4

56 3 ⁄4

401

1 ⁄2—

——

52 1 ⁄2

2 5 ⁄8

——

——

2 5 ⁄8

—3

3 ⁄42

5 ⁄8A

) (H

) Fo

r av

aila

bili

ty o

f st

eel p

ipe

size

s, r

efer

to

BS

EN 1

0216

, BS

EN 1

0217

. See

BS

4622

an

d B

S 47

22 f

or

ou

tsid

e d

iam

eter

s o

f ca

st ir

on

pip

es. S

ee B

S EN

124

49 f

or

the

size

s o

f co

pp

er p

ipes

fo

r u

se w

ith

co

pp

er a

lloy

flan

ges

up

to

8 in

bo

re.

B)

(O)

For

1 ⁄2 in

an

d 5 ⁄8

in b

olt

s, t

he

dia

met

ers

of

the

ho

les

shal

l be

1 ⁄16

in la

rger

th

an t

he

bo

lts

and

fo

r 3 ⁄4

in b

olt

s an

d s

izes

ab

ove

, th

e d

iam

eter

s sh

all b

e n

ot

mo

re t

han

1 ⁄8 in

larg

er t

han

th

e b

olt

s.

For

cast

iro

n fl

ang

es t

he

dia

met

ers

of

the

bo

lt h

ole

s m

ay b

e 1 ⁄8

in la

rger

th

an t

he

bo

lts

of

size

s 5 ⁄8

in a

nd

ab

ove

.C

) (A

. B &

E)

Tap

ers

are

no

t sp

ecifi

ed b

ut

shal

l be

such

th

at t

he

max

imu

m d

iam

eter

s at

ro

ot

of

bo

ss a

re n

ot

exce

eded

.D

) (K

) Th

e d

iam

eter

s ta

bu

late

d a

pp

ly t

o p

ipes

wit

h o

uts

ide

dia

met

ers

in a

cco

rdan

ce w

ith

H. F

or

pip

es d

esig

nat

ed b

y th

eir

bo

res,

dim

ensi

on

K s

hal

l be

such

th

at t

he

dif

fere

nce

bet

wee

n t

he

corr

esp

on

din

g d

iam

eter

s K

an

d H

is m

ain

tain

ed.

E)

(T7)

It is

imp

ract

icab

le t

o u

se t

hic

knes

s le

ss t

han

1 ⁄2 in

exc

ept

for

bo

ss fl

ang

es o

r in

teg

ral fl

ang

es.

F)

(H)

It is

rec

om

men

ded

th

at t

his

siz

e fo

r st

eel p

ipes

sh

ou

ld b

e av

oid

ed w

her

ever

po

ssib

le.

Page 22

BS 10:2009

16 • © BSI 2009

BRITISH STANDARD BRITISH STANDARD

© BSI 2009 • 17

BS 10:2009Ta

ble

H

Dim

ensi

on

s o

f p

lain

, bo

ss, i

nte

gra

lly c

ast

or

forg

ed, a

nd

wel

din

g n

eck

flan

ges

(fo

r ra

tin

gs

see

Tab

le 2

an

d A

nn

ex B

)

Flan

ge

size

des

-ig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

x-im

ate

ou

tsid

e d

iam

-et

er o

f st

eel

pip

e A

)

Dia

m-

eter

of

flan

ge

Bo

lt

circ

le

dia

m-

eter

No

. o

f b

olt

s

Dia

m-

eter

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(F

ig. 4

) C

)D

imen

sio

ns

of

nec

ks f

or

cast

ir

on

(Fi

g. 7

)

Dim

ensi

on

s o

f st

eel w

eld

ing

n

ecks

(Fi

g. 6

)D

iam

eter

o

f ra

ised

fa

ce (

see

Cla

use

4)

(Fig

s 3,

4,

5, 6

)

Thic

knes

s o

f fl

ang

e

Bo

ss

len

gth

Dia

m-

eter

at

smal

l en

d

of

bo

ss

Max

i-m

um

d

iam

-et

er a

t ro

ot

of

bo

ss

Dia

m-

eter

at

larg

e en

d o

f n

eck

Len

gth

o

f ta

per

Dia

m-

eter

at

larg

e en

d

of

nec

k

Dia

m-

eter

at

smal

l en

d o

f n

eck

D)

Tota

l le

ng

th

of

nec

k

Len

gth

o

f ta

per

Gre

y ca

st ir

on

in

te-

gra

lly

cast

or

scre

wed

o

n w

ith

b

oss

Co

pp

er

allo

y ca

st o

r w

rou

gh

t in

teg

ral

or

bo

ss

or

pla

in

(Fig

. 3)

Cas

t o

r w

rou

gh

t st

eel i

nte

-g

ral o

r p

lain

(F

ig. 3

) o

r b

oss

(Fi

g. 4

) o

r w

eld

ing

n

eck

(Fig

. 6)

(exc

ept

for

valv

es)

Forg

ed

or

cast

st

eel

inte

-g

ral

(Fig

. 5)

(fo

r va

lves

o

nly

)

HD

PN

OA

BE

CG

JK

LM

FT 1

T 3T 7

T 9in

inin

inin

inin

inin

inin

inin

inin

inin

inin

1⁄2

27 ⁄3

24

1 ⁄23

1 ⁄44

5⁄8

3⁄8

1 5 ⁄1

61

7 ⁄81

1⁄2

1 3 ⁄1

6 7⁄8

1 1 ⁄8

5⁄8

2 1 ⁄4

5⁄8

3⁄8

1⁄2

1⁄2

3⁄4

1 1 ⁄1

64

1 ⁄23

1 ⁄44

5⁄8

7⁄16

1 1 ⁄2

1 7 ⁄8

1 3 ⁄8

1⁄2

1 3 ⁄8

1 3 ⁄3

21

1 ⁄8 5⁄8

2 1 ⁄4

5⁄8

3⁄8

1⁄2

1⁄2

11

11⁄32

4 3 ⁄4

3 7 ⁄1

64

5⁄8

7⁄16

1 7 ⁄8

2 1 ⁄1

61

3 ⁄4 1⁄2

1 11

⁄161

3 ⁄81

1 ⁄8 5⁄8

2 1 ⁄2

3⁄4

7⁄16

9⁄16

9⁄16

1 1 ⁄4

1 11

⁄165

1 ⁄43

7 ⁄84

5⁄8

7⁄16

2 3 ⁄1

62

1 ⁄22

1 ⁄8 5⁄8

2 1 ⁄1

61

23⁄32

1 3 ⁄8

3⁄4

3 7⁄8

7⁄16

11 ⁄1

6 1

1 ⁄16

1 1 ⁄2

1 29

⁄325

1 ⁄24

1 ⁄84

5⁄8

1⁄2

2 7 ⁄1

62

3 ⁄42

1 ⁄2 5⁄8

2 5 ⁄1

61

15⁄16

1 3 ⁄8

3⁄4

3 1 ⁄4

7⁄8

1⁄2

11 ⁄1

6 1

1 ⁄16

22

3 ⁄86

1 ⁄25

4 5⁄8

1⁄2

2 15

⁄163

21⁄32

3 1 ⁄8

3⁄4

2 3 ⁄4

2 13

⁄321

3 ⁄8 3⁄4

41

1⁄2

3⁄4

3⁄4

2 1 ⁄2

37

1 ⁄45

3 ⁄48

5⁄8

5⁄8

3 9 ⁄1

64

13⁄32

3 3 ⁄4

3⁄4

3 3 ⁄8

3 1 ⁄3

21

1 ⁄2 3⁄4

4 1 ⁄2

1 9⁄16

3⁄4

3⁄4

33

1 ⁄28

6 1 ⁄2

8 5⁄8

5⁄8

4 3 ⁄1

65

1 ⁄84

1 ⁄2 3⁄4

43

17⁄32

1 3 ⁄4

15

1 1 ⁄8

5⁄8

7⁄8

7⁄8

3 1 ⁄2

48

1 ⁄27

8 5⁄8

11 ⁄1

64

11⁄16

5 21

⁄325

1 ⁄8 7⁄8

4 1 ⁄2

4 1 ⁄1

61

3 ⁄41

5 1 ⁄2

1 1 ⁄8

11 ⁄1

6 7⁄8

7⁄8

44

1 ⁄29

7 1 ⁄2

8 5⁄8

3⁄4

5 1 ⁄4

65

5 ⁄8 7⁄8

5 1 ⁄8

4 9 ⁄1

62

1 1 ⁄4

61

1 ⁄4 3⁄4

11

55

1 ⁄211

9 1 ⁄4

8 3⁄4

3⁄4

6 5 ⁄1

67

1 ⁄26

3 ⁄41

6 1 ⁄4

5 9 ⁄1

62

1 ⁄41

1 ⁄27

1 3 ⁄8

7⁄8

1 1 ⁄8

1 1 ⁄8

66

1 ⁄212

10 1 ⁄4

12 3⁄4

3⁄4

7 5 ⁄1

68

1 ⁄27

7 ⁄81

7 1 ⁄4

6 9 ⁄1

62

1 ⁄41

1 ⁄28

1 ⁄41

3 ⁄81

1 1 ⁄8

1 1 ⁄8

6 5 ⁄8

6 23

⁄32

77

5 ⁄813

1 ⁄411

1 ⁄212

3⁄4

7⁄8

8 3 ⁄8

9 13

⁄169

1 ⁄81

8 3 ⁄8

7 23

⁄322

1 ⁄41

1 ⁄29

1 ⁄41

1 ⁄21

1 ⁄81

1 ⁄41

1 ⁄4

88

5 ⁄814

1 ⁄212

3 ⁄412

3⁄4

7⁄8

9 1 ⁄2

1110

1 ⁄41

1 ⁄89

1 ⁄28

23⁄32

2 5 ⁄8

1 3 ⁄4

10 1 ⁄4

1 1 ⁄2

1 1 ⁄4

1 1 ⁄4

1 1 ⁄4

99

5 ⁄816

1412

7⁄8

110

1 ⁄211

15⁄16

11 3 ⁄8

1 1 ⁄8

10 5 ⁄8

9 3 ⁄4

2 7 ⁄8

211

1 ⁄41

5 ⁄81

3 ⁄81

3 ⁄81

3 ⁄8

1010

3 ⁄417

1512

7⁄8

1 1 ⁄1

611

3 ⁄412

15⁄16

12 3 ⁄8

1 1 ⁄8

11 3 ⁄4

10 7 ⁄8

2 7 ⁄8

212

1 ⁄41

5 ⁄81

3 ⁄81

3 ⁄81

3 ⁄8

1212

3 ⁄419

1 ⁄417

1 ⁄416

7⁄8

1 1 ⁄8

13 3 ⁄4

15 3 ⁄1

614

5 ⁄81

1 ⁄413

7 ⁄812

29⁄32

3 1 ⁄8

2 1 ⁄4

14 1 ⁄4

1 3 ⁄4

1 1 ⁄2

1 5 ⁄8

1 1 ⁄2

1314

20 3 ⁄4

18 1 ⁄2

161

——

—15

3 ⁄41

1 ⁄415

1 ⁄414

5 ⁄32

3 3 ⁄8

2 1 ⁄2

15 1 ⁄2

1 7 ⁄8

1 5 ⁄8

1 3 ⁄4

1 5 ⁄8

1415

E)21

3 ⁄419

1 ⁄216

1—

——

16 3 ⁄4

1 3 ⁄8

16 1 ⁄4

15 5 ⁄3

23

3 ⁄82

1 ⁄216

1 ⁄21

7 ⁄81

5 ⁄81

7 ⁄81

5 ⁄8

1516

22 3 ⁄4

20 1 ⁄2

161

——

—17

7 ⁄81

3 ⁄817

1 ⁄416

3 ⁄16

3 3 ⁄8

2 1 ⁄2

17 1 ⁄2

21

3 ⁄42

1 3 ⁄4

16—

2421

3 ⁄420

1—

——

191

3 ⁄8—

——

—19

21

3 ⁄42

1 ⁄81

3 ⁄4

1718

25 1 ⁄4

2320

1—

——

20 1 ⁄8

1 1 ⁄2

——

——

202

1 ⁄81

7 ⁄82

1 ⁄41

7 ⁄8

Page 23

BS 10:2009

16 • © BSI 2009

BRITISH STANDARD BRITISH STANDARD

© BSI 2009 • 17

BS 10:2009

Tab

le H

D

imen

sio

ns

of

pla

in, b

oss

, in

teg

rally

cas

t o

r fo

rged

, an

d w

eld

ing

nec

k fl

ang

es (

for

rati

ng

s se

e Ta

ble

2 a

nd

An

nex

B)

(co

nti

nu

ed)

Flan

ge

size

des

-ig

nat

ion

(n

om

inal

b

ore

of

pip

e)

Ap

pro

x-im

ate

ou

tsid

e d

iam

-et

er o

f st

eel

pip

e A

)

Dia

m-

eter

of

flan

ge

Bo

lt

circ

le

dia

m-

eter

No

. o

f b

olt

s

Dia

m-

eter

of

bo

lts

B)

Dim

ensi

on

s o

f b

oss

(F

ig. 4

) C

)D

imen

sio

ns

of

nec

ks f

or

cast

ir

on

(Fi

g. 7

)

Dim

ensi

on

s o

f st

eel w

eld

ing

n

ecks

(Fi

g. 6

)D

iam

eter

o

f ra

ised

fa

ce (

see

Cla

use

4)

(Fig

s 3,

4,

5, 6

)

Thic

knes

s o

f fl

ang

e

Bo

ss

len

gth

Dia

m-

eter

at

smal

l en

d

of

bo

ss

Max

i-m

um

d

iam

-et

er a

t ro

ot

of

bo

ss

Dia

m-

eter

at

larg

e en

d o

f n

eck

Len

gth

o

f ta

per

Dia

m-

eter

at

larg

e en

d

of

nec

k

Dia

m-

eter

at

smal

l en

d o

f n

eck

D)

Tota

l le

ng

th

of

nec

k

Len

gth

o

f ta

per

Gre

y ca

st ir

on

in

te-

gra

lly

cast

or

scre

wed

o

n w

ith

b

oss

Co

pp

er

allo

y ca

st o

r w

rou

gh

t in

teg

ral

or

bo

ss

or

pla

in

(Fig

. 3)

Cas

t o

r w

rou

gh

t st

eel i

nte

-g

ral o

r p

lain

(F

ig. 3

) o

r b

oss

(Fi

g. 4

) o

r w

eld

ing

n

eck

(Fig

. 6)

(exc

ept

for

valv

es)

Forg

ed

or

cast

st

eel

inte

-g

ral

(Fig

. 5)

(fo

r va

lves

o

nly

)

HD

PN

OA

BE

CG

JK

LM

FT 1

T 3T 7

T 9in

inin

inin

inin

inin

inin

inin

inin

inin

inin

18—

26 1 ⁄2

2420

1 1 ⁄8

——

—21

1 ⁄41

1 ⁄2—

——

—21

2 1 ⁄8

1 7 ⁄8

2 3 ⁄8

1 7 ⁄8

1920

27 3 ⁄4

25 1 ⁄4

201

1 ⁄8—

——

22 3 ⁄8

1 1 ⁄2

——

——

22 1 ⁄2

2 1 ⁄4

22

1 ⁄22

20—

2926

1 ⁄224

1 1 ⁄8

——

—23

1 ⁄21

5 ⁄8—

——

—23

1 ⁄22

1 ⁄42

2 5 ⁄8

2

2122

3027

1 ⁄224

1 1 ⁄8

——

—24

1 ⁄21

5 ⁄8—

——

—24

1 ⁄22

3 ⁄82

1 ⁄82

3 ⁄42

1 ⁄8

22—

3128

1 ⁄224

1 1 ⁄8

——

—25

1 ⁄21

3 ⁄4—

——

—25

1 ⁄22

3 ⁄82

1 ⁄82

3 ⁄42

1 ⁄8

2324

32 1 ⁄2

29 3 ⁄4

241

1 ⁄4—

——

26 1 ⁄2

1 3 ⁄4

——

——

26 1 ⁄2

2 1 ⁄2

2 1 ⁄4

32

1 ⁄4

24—

33 1 ⁄2

30 3 ⁄4

241

1 ⁄4—

——

281

3 ⁄4—

——

—27

1 ⁄22

1 ⁄22

1 ⁄43

2 1 ⁄4

A)

(H)

For

avai

lab

ility

of

stee

l pip

e si

zes,

ref

er t

o B

S EN

102

16, B

S EN

102

17. S

ee B

S 46

22 a

nd

BS

4722

fo

r o

uts

ide

dia

met

ers

of

cast

iro

n p

ipes

. See

BS

EN 1

2449

fo

r th

e si

zes

of

cop

per

pip

es f

or

use

wit

h c

op

per

allo

y fl

ang

es u

p t

o 8

in b

ore

.B

) (O

) Fo

r 5 ⁄8

in b

olt

s, t

he

dia

met

ers

of

the

ho

les

shal

l be

1 ⁄16

in la

rger

th

an t

he

bo

lts

and

fo

r 3 ⁄4

in b

olt

s an

d s

izes

ab

ove

, th

e d

iam

eter

s sh

all b

e n

ot

mo

re t

han

1 ⁄8 in

larg

er t

han

th

e b

olt

s. F

or

cast

ir

on

flan

ges

th

e d

iam

eter

s o

f th

e b

olt

ho

les

may

be

1 ⁄8 in

larg

er t

han

th

e b

olt

s o

f si

zes

5 ⁄8 in

an

d a

bo

ve.

C)

(A. B

& E

) Ta

per

s ar

e n

ot

spec

ified

bu

t sh

all b

e su

ch t

hat

th

e m

axim

um

dia

met

ers

at r

oo

t o

f b

oss

are

no

t ex

ceed

ed.

D)

(K)

The

dia

met

ers

tab

ula

ted

ap

ply

to

pip

es w

ith

ou

tsid

e d

iam

eter

s in

acc

ord

ance

wit

h H

. Fo

r p

ipes

des

ign

ated

by

thei

r b

ore

s, d

imen

sio

n K

sh

all b

e su

ch t

hat

th

e d

iffe

ren

ce b

etw

een

th

e co

rres

po

nd

ing

dia

met

ers

K a

nd

H is

mai

nta

ined

.E)

(H

) It

is r

eco

mm

end

ed t

hat

th

is s

ize

for

stee

l pip

es s

ho

uld

be

avo

ided

wh

erev

er p

oss

ible

.