BS 2779-1986 英制非密封管螺纹(BSP)

非密封管螺纹

BRITISH STANDARD

BS2779:1986

Specification for

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Pipe threads for tubes and fittings where pressure-tight joints are not made on the threads (metric dimensions)

UDC621.643.414:621.882.082.1

非密封管螺纹

BS2779:1986

Committees responsible for this British Standard

This British Standard was entrusted by the Piping Systems Components

Standards Committee (PSE/-) to Technical Committee PSE/9, upon which the following bodies were represented:

British Hydromechanics Research AssociationBritish Malleable Tube Fittings AssociationBritish Steel Industry

British Valve Manufacturers Association Ltd.Copper Tube Fittings Manufacturers’ Association

Department of Trade and Industry (National Engineering Laboratory)Energy Industries Council

Engineering Equipment and Materials Users’ AssociationGauge and Tool Makers’ AssociationInstitution of Civil EngineersInstitution of Gas Engineers

Institution of Public Health Engineers

Institution of Water Engineers and ScientistsWater Authorities AssociationWater Companies Association

Wrought Fitting Makers’ Association

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This British Standard, having been prepared under the

direction of the Piping Systems Components Standards Committee, was published under the authority of the Board of BSI and comes into effect on 29 August1986 © BSI 12-1998

First published December1956 First revision April1973 Second revision August1986The following BSI references relate to the work on this standard:

Committee reference PSE/9 Draft for comment85/75381 DCISBN058015212 X

Amendments issued since publication

非密封管螺纹

BS2779:1986

Contents

Committees responsibleForeword

Page

Inside front cover

ii

11455685788910111213145910111314

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234Symbols

Classification and designationThread details

thread for class A external threads

Appendix B Notes on tolerancing system structureAppendix C Method of verification of thread size and form by means of limit gauges

Appendix D Gauges for the method given in appendix C

Figure 2 — Special truncated external threadFigure 3 — NOT GO screw calliper gaugeFigure 4 — Start of complete threadFigure 5 — Chamfer of start of thread

Figure 6 — Thread profiles of GO ring gauges and their check plugs

Figure 7 — Relative positions of pitch diameter tolerancezones for GO ring gauges and their check plugs

Figure 8 — Thread profiles of NOT GO ring gauges and their check plugs and calliper gauges

Figure 9 — Relative positions of pitch diameter tolerance zones for NOT GO ring gauges, calliper gauges and their check plugsFigure 10 — Thread profiles of Go and NOT GO plug gauges

Figure 11— Relative positions of pitch diameter tolerance zones for GO and NOT GO plug gauges

Table 2 — Special truncated fastening threads, class A external threads

Table 3 — Dimensions for GO and NOT GO gauges and their check plugs for class A external threads and for GO gauges and their check plugs for class B external threadsTable 4 — Other values for GO and NOT GO gauges and their check plugs for class A and class B external threads as a function of the pitch, P

Table 5 — Dimensions for NOT GO gauges and their check plugs for class B external threads

Table 6 — Dimensions for threaded GO and NOT GO plug gaugesTable 7 — Other values for GO and NOT GO plug gauges as a function of the pitch, P

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非密封管螺纹

BS2779:1986

Foreword

This revision of BS2779 has been prepared under the direction of the Piping Systems Components Standards Committee. It supersedes BS2779:1973, which is withdrawn.

This standard is based on and is technically equivalent to the two Parts of

ISO228 “Pipe threads where pressure-tight joints are not made on the threads”, namely ISOonly.

For ease of production, it has been found convenient to reproduce the figures from ISO228/2-1980 forFigure4,Figure5,Figure7,Figure10 andFigure11 of this standard.

A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct pliance with a British Standard does not of itself confer immunity from legal obligations.

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Summary of pages

This document comprises a front cover, an inside front cover pages i and ii, pages1 to14, aninside back cover and a back cover.

This standerd has been updated (see copyright date) and may have had

amendments incorporated. This will be indicated in the amendment table on theinside front cover.

ii

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非密封管螺纹

BS2779:1986

1 Scope

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This British Standard specifies requirements for the designation and dimensions of Whitworth form

Tdfastening pipe threads having a thread size

designation in the range1/16 to6 inclusive. This standard applies to pipe threads where Td2

1)

pressure-tight joints are not made on the threads.

Dimensions are given in metric units. The tolerance TD1on the crests of the threads allows for truncation (see4.1).

TD,2

NOTE1The pipe threads covered by this standard are

generally used for fastening purposes, such as the mechanical assembly of the component parts of fittings, cocks and valves, etc.NOTE2The titles of the publications referred to in this standard are listed on the inside back cover.

Tcp

TPLTRuWGO

2 Symbols

For the purposes of this British Standard, the following symbols apply.

Symbol

Term

b3dd1d2DD1D2hHm

Width of clearance groove at the major and minor diameter of the thread profile with

WNGshortened flanks.

Basic major diameter of the external thread.

ZPL

Basic minor diameter of the external thread (d1 = d –1.280654P).

Basic pitch diameter of the external thread

ZR

(d2 = d –0.640327 P).

Basic major diameter of the internal thread (D = d).

Basic minor diameter of the internal thread (D1 = D –1.280654P = d1).

Tolerance on the pitch diameter of GO and NOT GO threaded check plugs and wear check plugs.

Tolerance on the basic major diameter of the external thread.

Tolerance on the basic pitch diameter of the external thread.

Tolerance on the basic minor diameter of the internal thread.

Tolerance on the basic pitch diameter of the internal thread.

Tolerance on the pitch diameter of GO and NOT GO threaded plug gauges.

Tolerance on the pitch diameter of GO and NOT GO threaded ring gauges.

A length equal to twice the radial height of rounding at crest of root and thread (u =0.14784P).

Average amount available for the permissible wear of GO threaded plug gauge and GO threaded ring gauge.Average amount available for the

permissible wear of NOT GO threaded plug gauge and NOT GO threaded ring gauge.Distance between the middle of the

tolerance zone TPL of the GO threaded plug gauge and the lower limit of the thread.Distance between the middle of the

tolerance zone TR of the GO threaded ring gauge and the upper limit of the thread.

3 Classification and designation

PrsS

3.1 Classes of external and internal threads

Basic pitch diameter of the internal thread

For internal threads, one class of tolerance on the (D2 = D –0.640327P = d2).

pitch diameter has been provided. For external

Height of the thread profile with rounded threads, two classes of tolerance on the pitch crests and roots.diameter have been established, as follows:Height of the triangle of the thread profile.a) class A tolerance, entirely negative value

equivalent to the internal thread tolerance Distance between the middle of the

(seeTable1);tolerance zone TR of the threaded ring

b) class B tolerance, entirely negative value twice gauge and the middle of the tolerance zone

that of the class A tolerance (seeTable1).TCP of the GO check plug.

Pitch.

shortened flanks.Tolerance on b3.

NOTE1Where no class reference is stated, class B should be assumed.

NOTE2The tolerance zones are shown inFigure1.

NOTE3The choice of fit for a particular purpose rests with the purchaser’s designer.

1)

Reference should be made to BS21 for requirements for pipe threads where pressure-tight joints are made on the threads.

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BS2779:1986

3.2 Designation

Internal and external threads shall be designated by the letter “G” followed by the thread size designation given inTable1, and, for external

threads, the class reference: for example, G ½ for an NOTEassumed.

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Where threads are full form (see4.1.2“F” shall be added to the designation, e.g. G ½ F for internal threads and G ½ AF for class A external threads.

Where external threads have the special truncated Whit-worth form in accordance withTable2, the letter “T” shall be added to the designation, e.g. G ½ AT.

2

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Table1 — Basic dimensions and tolerances

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BS2779:1986

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非密封管螺纹

BS2779:1986

4 Thread details

4.1 Form of thread

4.3 Compliance

NOTENo method is specified for verification of compliance with the requirements of4.1 and4.2, but the method described in appendix C, using the gauges described in appendix D, is recommended.

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information on the tolerancing system structure. Tolerance zones are shown inFigure1.

NOTE2The tolerances for the basic pitch diameter of internal threads given inTable1 correspond to the positive deviation of the tolerances on the diameter specified in BS21, with the exception of the tolerances for the following thread size

designations, for which slightly higher tolerances have been specified:

1/16, 1/8, 1/4, 3/8, 21/2,3,4,5, and6.

If tested in accordance with appendices C and D, the threads shall be deemed to comply with the

4.1.2 standard if they are in accordance with the

following.shall have one of the following forms:

a) For external threads: a) the full form, as shown inFigure1) with the solid threaded GO ring gauge, the b) the truncated form, with crests truncated to

gauge shall pass over the whole length of the the tolerances given inTable1.

thread;NOTEThe form of thread should be agreed between the

manufacturer and the purchaser.2) with the NOT GO screw calliper gauge, at any

position, the gauge shall not pass over a 4.1.3 For external threads, the crests of the thread

threaded part, except for the first two threads shall have one of the following forms:

of the part thread;a) the full form, as shown inFigure1; or

3) with the solid threaded NOT GO ring gauge, b) the truncated form, with crests truncated to

using either side of the gauge, it shall not be the tolerances given inTable1; or

possible to screw the gauge on to the thread by

c) for class A threads only, the special truncated more than two turns of thread. In addition, the form, in accordance with appendix A.gauge shall not pass completely over a NOTEThe special truncated form of thread is used where threaded part having a length of three threads galling of the threads may occur.

or less.

4.2 Dimensions and tolerances

b) For internal threads:

4.2.1 Dimensions. The basic dimensions for the 1) with the threaded GO plug gauge, the gauge threads shall be as given inTable1, except for class shall pass through the whole length of the A external threads with the special truncated form thread;[see4.1.3c)].

2) with the threaded NOT GO plug gauge, the

4.2.2 Tolerances. Tolerances for the major, pitch and gauge shall not enter either end of the thread minor diameters shall be as given inTable1, except by more than two turns of thread. In addition, for class A external threads with the special the gauge shall not pass completely through a truncated form [see4.1.3c)].threaded part with a length of three threads or NOTE1Reference should be made to appendix B for further less.

NOTEthread in BS21.

4.1.1 The basic form of the thread shall be the basic Whitworth form, as shown inFigure1.

Figure1 — Thread profile and tolerance zones

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BS2779:1986

Appendix A Special truncated form of the Whitworth thread for class A external threads

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Lengths of engagement are not specified; these will depend upon the application. However, for long lengths of engagement (e.g. more than15 pitches), it is essential that care be taken to ensure that there

The dimensions of the special truncated Whitworth is not excessive deviation from the pitch, roundness

or straightness of the threads, particularly when form shall be in accordance withTable2. The

using class A external threads.thread form shall be as shown inFigure2.

NOTE1These threads should only be supplied when specified

on a component drawing.

NOTE2In the truncated Whitworth form of external thread, the basic rounded crest at the major diameter is removed at the junction with the straight flanks of the basic thread form. This reduction from the basic major diameter is equal to0.14784P (seeFigure2). The resulting flat crest of the thread is given a suitable manufacturing tolerance.

Table2 — Special truncated fastening threads, class A external threads

of designationdiameterthreads

in

25.4 mm

11

/16/8

28281919141414141111

7.5909.59412.95916.46420.68622.64226.17229.93132.90841.570

0.122 0.122 0.144 0.144 0.170 0.170 0.170 0.170 0.198 0.198

7.4689.47212.81516.32020.51622.47226.00229.76132.71041.372

Figure2 — Special truncated external

thread

1/43/81/25/837

/4/8

1

Tolerances are not specified for the minor diameters

1/4of external threads nor for the major diameters of

internal threads. In practice, these diameters will 1147.462 0.19847.26411/2

be controlled by the profiles of the tools used to cut the threads. The minor diameter of external threads

Appendix B Notes on tolerancing should not be greater than the basic minor system structurediameter, while the major diameter of internal InTable1, the pitch diameter tolerances, which are threads should not be smaller than the basic major intended to include the diametral effect of pitch and diameter.

angle errors, have been calculated from the general It should be noted that the internal thread minor formula:0.0625 multiplied by the deviation on the diameter tolerances are such as to permit a tapping

drill of ample size to be used. If full advantage is internal thread length of BS

21. Thus:

taken of these generous minor diameter tolerances, the crests of the internal threads will be flat. It threads=+should also be noted that the external thread major

diameter tolerances are generally such as to permit

threads = crests which do not have a complete radius.

threads = 0.125 × length deviation.

1

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BS2779:1986

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Errors in the pitch and flank angles of a thread virtually increase the pitch diameter of an external thread and decrease the pitch diameter of an internal thread. The minimum material limits stated inTable1 andTable2 apply to the simple in the flank angles and in the pitch over the length of engagement.

For thin-walled parts, the tolerances on pitch

diameters apply to the mean pitch diameter, which is the arithmetical mean of two diameters measured at right angles to each other.

C.1.2 Gauges. The gauges shall be in accordance with appendix D. Since the55° profile has different elements to be verified, it is necessary to provide for several GO and NOT GO gauges.

C.1.3 Control of solid threaded ring gauges

C.1.3.1 New gauges. Check the GO and NOT GO ring gauges with the GO check plug

(seeD.2.1.2 andD.2.2.2.1) of the appropriate size, by attempting to screw the check plug, by hand and without using excessive force, through the gauge. Check that the check plug will pass completely through the ring gauge.

Check that the maximum size of the pitch diameter of the ring gauge is not exceeded, either using the NOT GO check plug (seeD.2.1.2 andD.2.2.2.1) or by some other method. If the NOT GO check plug is used,

Appendix C Method of verification of attempt to screw the appropriate check plug, by thread size and form by means of limit hand and without using excessive force, into both

ends of the gauge. Remove the check plug, counting gauges

the turns of thread, and ensure that the check plug has not engaged the ring gauge by more than one C.1 External threads

turn. Record the number of turns of thread.

C.1.1 Principles

C.1.3.2 Checking for wear. Check the GO and NOT GO

C.1.1.1 Solid threaded GO ring gauge. The gauge ring gauges regularly with the appropriate wear checks the virtual size of the internal thread on the check plug (seeD.2.1.2 andD.2.2.2.1). Attempt to GO side, i.e. it gauges the virtual pitch diameter. screw the wear check plug, by hand and without This is done by checking the maximum material using excessive force, into both ends of the gauge. limit of the pitch diameter. During this process the Remove the check plug, counting the turns of following factors, which produce an apparent thread, and ensure that the check plug has not enlargement of the pitch diameter (represented by engaged the ring gauge by more than one turn. the dimension, virtual pitch diameter), are taken Record the number of turns of thread.into account.

C.1.4 Procedure for gauging threads

a) Deviations from the form.

C.1.4.1 Solid threaded GO ring gauge. Without using

b) Departures from roundness.

excessive force, attempt to screw the gauge by hand

c) Lack of straightness of the thread axis over the over the whole length of the thread.gauge length.

C.1.4.2 Solid threaded NOT GO ring gauge. Without

d) Pitch ing excessive force and using either side of the e) Helix variations.gauge, screw the gauge by hand on to the thread for

as many turns as possible. Unscrew the gauge and f) Errors in the flank angles.

record the number of turns engaged.

In addition, this gauge checks that the rounding at

the root of the profile does not encroach too far upon C.1.4.3 NOT GO screw calliper gaugethe flank of the thread. It also verifies that the C.1.4.3.1 Setting the gauge. Use the setting plug thread crest form does not transgress the maximum appropriate to the gauge in use to set the anvils of material profile.the gauge. Attempt to pass the gauge over the plug, C.1.1.2 NOT GO Screw Calliper Gauge. The gauge is under its own weight or under a fixed ed to check the minimum limit of the pitch NOTEThe gauge may be moved slightly to and fro in a

circumferential direction during this process.diameter.

If the gauge will not pass over the plug or if there is C.1.1.3 Solid threaded NOT GO ring gauge. The

a clearance, adjust the anvils of the gauge and gauge is used to check whether the actual pitch

repeat the procedure.diameter exceeds the specified minimum size.

6

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d) Pitch errors.e) Helix variations.

f) Errors in the flank angles.

In addition, this gauge checks both the minimum NOTEThe gauge may be moved slightly to and fro in a

limit of the major diameter and also that the circumferential direction during this process.

rounding at the root of the profile does not encroach If the gauge shown in Figure3(b) is used, repeat

too far upon the flank of the thread.each check after having displaced the gauge from

C.2.1.2 Threaded NOT GO plug gauge. The gauge is one pitch to the other.

Record the positions of the thread the gauge passes used to check whether the actual pitch diameter

exceeds the specified maximum size.over.

C.2.2 Gauges. The gauges shall be in accordance

C.2 Internal threadswith appendix D.

C.2.3 Control of plug gauges. Examine the GO and C.2.1 Principles

NOT GO plug gauges regularly for wear by

C.2.1.1 Threaded GO plug gauge. The gauge checks

measurement.

the virtual size of the internal thread on the GO side,

i.e. it gauges the virtual pitch diameter. This is done NOTEThe worn threads of a NOT GO plug gauge may be

removed, provided that at least three turns of thread remain.

by checking the minimum material limit of the pitch

diameter. During this process the following factors, C.2.4 Procedure for gauging threadswhich produce an apparent reduction of the pitch C.2.4.1 Threaded GO plug gauge. Without using diameter (represented by the dimension, virtual excessive force, attempt to screw the gauge by hand pitch diameter), are taken into account.through the whole length of the thread.a) Deviations from the form.C.2.4.2 Threaded NOT GO plug gauge. Without using

excessive force, screw the gauge by hand into the b) Departures from roundness.

thread for as many turns as possible. Unscrew the

c) Lack of straightness of the thread axis over the

gauge and record the number of turns engaged.

gauge length.C.1.4.3.2 Main procedure. In at least three positions evenly distributed over the circumference, attempt to pass the gauge over the thread, under its own weight or under a fixed load.

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Appendix D Gauges for the method given in appendix CLicensed Copy: AUB User, na, Sun Mar 25 13:38:08 GMT+00:00 2007, Uncontrolled Copy, (c) BSI

D.1 General

D.1.1 Taylor principle. All gauges and their setting possible, except for the solid threaded NOTgauge.

D.2 Ring gauges and calliper gauges for external threadsD.2.1 GO sideD.2.1.1 Gauges

D.2.1.1.1 Solid threaded GO ring gauges for class A and class B external threads shall be in accordance withTable3 andTable4. Ring gauge thread profiles shall be as shown in Figure6.

NOTE1

NOTE1The Taylor principle is a statement to the effect that the maximum material limits of as many related elements or dimensions as practicable should be incorporated in the GO gauge, whereas the minimum material limit of each related element or dimension may be gauged only by individual minimum material limit gauges or gauging methods.NOTE2Checking with a solid threaded NOT GO ring gauge does not correspond to the Taylor principle. For non-rigid machined pieces, the departure from the Taylor principle is of less importance because of the flexibility of the pieces.

The values of d, d1 and d2 shall be as given inTable1.

NOTE2The values specified inTable3 andTable4 for pitch, P, and tolerance on basic pitch diameter, T d2, are identical with those given inTable1.

Tolerance zones are shown inFigure7.

D.1.2 Entry of the thread, incomplete threads, even if they are chamfered, are still sharp enough to break or deform. In order that checking will not be affected, it is recommended that the incompletely formed part of the thread be removed (seeFigure4) or, if this is not possible, that a chamfer to the thread root of27°30′ be applied (seeFigure5).

D.2.1.1.2 The length of the thread on the gauge shall be at least80 % of the thread length of the engaging part or component (i.e. the thread length of, for example, a nut).D.2.1.2 Check plugs

NOTEThe GO and NOT GO check plugs for the solid threaded GO ring gauge are used to check the limits of the pitch diameter of a new gauge. The wear check plug is used to ascertain that the pitch diameter of the solid threaded GO ring gauge has not exceeded the wear limit. It embodies the pitch diameter of the solid threaded GO ring gauge at the prescribed limit of wear.

GO, NOT GO and wear check plugs for ring gauges for

class A and class B external threads shall be in accordance withD.2.1.1.1.D.2.2 NOT GO side

D.2.2.1 Gauges

D.2.2.1.1 Solid threaded NOT GO ring gauges and NOT GO screw calliper gauges for class A external threads shall be in accordance-withTable3

andTable4. Ring gauges and calliper gauges for class B external threads shall be in accordance withTable4 andTable5. Thread profiles shall be shown inFigure8.

The values of d, d1 and d2 shall be as given inTable1.

NOTE

Tolerance zones are shown inFigure9.

Figure4 — Start of complete thread

Figure

5 — Chamfer of start of thread

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BS2779:1986

Table3 — Dimensions for GO and NOT GO gauges and their check plugs for class A external

threads and for GO gauges and their check plugs for class B external threads

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111

/16 and 1/8a/4 and 3/8

107

15

10

9910101313

1717

22

1313

1818

125142180217217

1520202525

1012121515

/2 up to and including 7/81 up to and including221/4 up to and including441/2 up to and including6

20202424

991313

17172121

23232828

168millimetres, increased by the following.

(d1 +0.134 + TR/2) ± TR/2 = d1 +0.142 ±0.0075 [seeFigure6(a)].

9

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BS2779:1986

Table4 — Other values for GO and NOT GO gauges and their check plugs for class A

and class B external threads as a function of the pitch, P

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Figure7 — Relative positions of pitch diameter tolerance zones for GO ring gauges

and their check plugs

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Figure8 — Thread profiles of NOT GO ring gauges and their check plugs

and calliper gauges

Table5 — Dimensions for

NOT GO gauges and their check plugs for class B external threads

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BS2779:1986

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shall have a length of thread of at least three turns of thread. Each anvil of the NOT GO screw calliper gauge shall be so designed that it contacts the

machined piece thread on no more than two flanks [seeFigure3(a) and (b)]. On fine pitch gauges, these flanks shall be situated not more than three pitches apart.

D.2.2.2 Check plugs and setting plugsD.2.2.2.1 Check plugs for NOT GO ring gauge

gauge.

Setting plugs shall be in accordance withD.2.2.1.1. Each setting plug shall have at least three complete threads.

D.3 GO and NOT GO plug gauges

The gauges shall be in accordance withTable6 andTable7. Thread profiles shall be as shown inFigure10.

NOTETolerance zones are shown inFigure11.NOTEThe GO and NOT GO check plugs for the solid threaded

NOT GO ring gauge are used to check the pitch diameter limits of The values of D, D1 and D2 shall be as given a new gauge. The threaded GO check plug makes sure that the

clearance diameter of the gauge is not too small. The wear check inTable1.

plug is used to check whether the pitch diameter of the gauge has The length of thread on the GO plug gauge shall be exceeded the wear limit. It embodies the pitch diameter of the

at least80% of the thread length of the engaging threaded NOT GO ring gauge at the prescribed limit of wear.GO, NOT GO and wear check plugs for ring gauges for

class A and class B external threads shall be in

accordance withD.2.2.1.1.

part or component (i.e. the thread length of, for example, a nut). The NOT GO plug gauge shall have a length of thread of at least three complete threads.

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Table6 — Dimensions for threaded GO and NOT GO plug gauges

D2PL

PLNGGOLicensed Copy: AUB User, na, Sun Mar 25 13:38:08 GMT+00:00 2007, Uncontrolled Copy, (c) BSI

111

/16 and 1/8a/4 and 3/8

/2 up to and including 7/8

107125142180217217

8813131818

101012121515

101013131717

141419192323

1 up to and including2

21/4 up to and including441/2 up to and including6

168GOmillimetres, increased by the following:

(D –0.134 – TPL/2) ± TPL/2 = D –0.139 ±0.005 (seeFigure10)

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Table7 — Other values for GO and NOT GO plug gauges as a function of the pitch, P

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Figure11 — Relative positions of pitch diameter tolerance zones

for GO and Not Go plug gauges

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BS2779:1986

Publications referred to

BS21, Specification for pipe threads for tubes and fittings where pressure-tight joints are made on the threads (metric dimensions).

ISO228, Pipe threads where pressure-tight joints are not made on the threads2).Part1 Designation, dimensions and tolerances.Part2 Verification by means of limit gauges.

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2) Referred to in the foreword only.

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BSI

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BSIistheindependentnationalbodyresponsibleforpreparingBritishStandards.ItpresentstheUKviewonstandardsinEuropeandattheinternationallevel.ItisincorporatedbyRoyalCharter.Revisions

ersofBritishStandardsshouldpossessthelatestamendmentsoreditions.

ItistheBSItoimprovethequalityofourproductsandservices.Wewouldbefindinganinaccuracyorambiguitywhileusingthis

BritishinformtheSecretaryofthetechnicalcommitteeresponsible,theidentityofwhichcanbefoundontheinsidefrontcover.Tel:02089969000.Fax:02089967400.

BSIoffersmembersanindividualupdatingservicecalledPLUSwhichensuresthatsubscribersautomaticallyreceivethelatesteditionsofstandards.Buyingstandards

OrdersforallBSI,internationalandforeignstandardspublicationsshouldbeaddressedtoCustomerServices.Tel:02089969001.Fax:02089967001.

Inresponsetoordersforinternationalstandards,itisBSIpolicytosupplytheBSIimplementationofthosethathavebeenpublishedasBritishStandards,rmationonstandards

BSIprovidesawiderangeofinformationonnational,EuropeanandinternationalstandardsthroughitsLibraryanditsTechnicalHelptoExportersService.VariousBSIelectronicinformationservicesarealsoavailablewhichgivedetailsonallitsproductsandservices.ContacttheInformationCentre.Tel:02089967111.Fax:02089967048.

SubscribingmembersofBSIarekeptuptodatewithstandardsdevelopmentsandreceivesubstantialdiscountsonthepurchasepriceofstandards.FordetailsoftheseandotherbenefitscontactMembershipAdministration.Tel:02089967002.Fax:02089967001.Copyright

CopyrightsubsistsinallBSIpublications.BSIalsoholdsthecopyright,intheUK,ofthepublicationsoftheinternationalstandardizationbodies.ExceptaspermittedundertheCopyright,DesignsandPatentsAct1988noextractmaybereproduced,storedinaretrievalsystemortransmittedinanyformorbyanymeans±electronic,photocopying,recordingorotherwise±withoutpriorwrittenpermissionfromBSI.Thisdoesnotprecludethefreeuse,inthecourseofimplementingthestandard,ofnecessarydetailssuchassymbols,andsize,typeorgradedesignations.IfthesedetailsaretobeusedforanyotherpurposethanimplementationthenthepriorwrittenpermissionofBSImustbeobtained.

Ifpermissionisgranted,thetermsmayincluderoyaltypaymentsoralicensingagreement.DetailsandadvicecanbeobtainedfromtheCopyrightManager.Tel:02089967070.

Licensed Copy: AUB User, na, Sun Mar 25 13:38:08 GMT+00:00 2007, Uncontrolled Copy, (c) BSI

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