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Bsi bs a 299 1989 (2000) iso 5857 1988

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BRITISH STANDARD AEROSPACE SERIES BS A 299 1989 ISO 5857 1988 Specification for Procurement of alloy steel protruding head bolts with strength classification 1 250 MPa and MJ threads Reproduced by IHS[.]

BRITISH STANDARD AEROSPACE SERIES Specification for Procurement of alloy steel protruding head bolts with strength classification 250 MPa and MJ threads Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy BS A 299:1989 ISO 5857:1988 BS A 299:1989 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Aerospace Standards Policy Committee (ACE/- ) to Technical Committee ACE/1 upon which the following bodies were represented: Civil Aviation Authority (Airworthiness Division) Electronic Engineering Association Ministry of Defence Society of British Aerospace Companies Limited This British Standard, having been prepared under the direction of the Aerospace Standards Policy Committee, was published under the authority of the Board of BSI and comes into effect on Amendments issued since publication 31 October 989 © BSI 01 - 2000 The following BSI references relate to the work on this standard: Committee reference ACE/1 Draft for comment 79/80725 DC ISBN 580 17460 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy Amd No Date of issue Comments BS A 299:1989 Contents Page Committees responsible Inside front cover National foreword ii Scope and field of application References Definitions Quality assurance Requirements Figure — Head structure and grain flow 14 Figure — Distortion in fillet area 15 Figure — Grain flow in thread 15 Figure — Non- permissible laps, seams and surface irregularities 16 Figure — Permissible laps, seams and surface irregularities 16 Figure — Metallurgical specimens 17 Table — Technical requirements and test methods Table — Qualification testing requirements for bolt samples Table — Summary of qualification and acceptance tests Table — Surface discontinuities and contamination Table — Minimum tensile, double shear and stress durability loads for qualification and acceptance tests 10 Table — Qualification and acceptance values for tension fatigue test 10 Table — Thread discontinuities — Maximum depth of permissible faults 10 Table — Classification of defects 11 Table — Sampling plans for visual inspection and inspection of dimensional characteristics 12 Table — Sampling plans for the inspection of mechanical and metallurgical characteristics 12 Table 1 — Variable sampling for tensile test (alternative method) Publications referred to © BSI 01 - 2000 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy 13 Inside back cover i BS A 299:1 989 National foreword This British Standard, which has been prepared under the direction of the Aerospace Standards Policy Committee, is identical with ISO 5857: 988 “Aerospace — Alloy steel protruding head bolts with strength classification 250 MPa and MJ threads — Procurement specification ” published by the International Organization for Standardization (ISO) Cross-references International Standard Corresponding British Standard ISO 2859- : 974 Sampling procedures for inspection by attributes Part : 972 Specification for sampling plans indexed by acceptable quality level (AQL) for lot-by-lot inspection BS 6001 (Technically equivalent) Statistical terminology Glossary of terms relating to probability and general terms relating to statistics ISO 3534: 977 BS 5532 Part : 978 (Identical) ISO 5855- 2: 981 BS 6293 MJ threads for aerospace construction Specification for dimensions for bolts Part 2: 982 and nuts (Identical) ISO 6508: 986 BS 891 Method for Rockwell hardness test Testing of metals Part : 962 (Technically equivalent) The Technical Committee has reviewed the provisions of ISO 6507- , to which reference is made in the text, and has decided that they are acceptable for use in conj unction with this standard A related British Standard to ISO 6507- : 982 is BS 427 “Method for Vickers hardness test ” Part : 961 “Testing of metals ” It is envisaged that a British Standard corresponding to ISO 7961 will be published A British Standard does not purport to include all the necessary provisions of a contract Users of British Standards are responsible for their correct application Compliance with a British Standard does not of itself confer immunity from legal obligations Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages to 8, an inside back cover and a back cover This standard has been updated (see copyright date) and may have had amendments incorporated This will be indicated in the amendment table on the inside front cover ii Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy © BSI 01 - 2000 BS A 99: 989 3.3.2 S cop e and fie ld of ap p lication se am This International Standard specifies the characteristics and quality assurance requirements open surface defect resulting from extension of the for bolts with protruding heads, made of alloy steel, material having a tensile strength classification 3.3.3 of 250 MPa and MJ threads, and intended for use lap in aerospace construction surface defect caused by folding over metal fins or This International Standard applies to bolts as sharp corners and then rolling or forging them into defined above, provided that reference is made to the surface this International Standard in the product standard 3.3.4 or definition document inclusions non- metallic particles originating from the material Re fe re nce s Sampling procedures for inspection by attributes — Part 1: Sampling plans indexed by acceptable quality level (AQL) for lot-by-lot inspection ) ISO 2859- , ISO 3534, Statistics — Vocabulary and symbols Aerospace construction — MJ threads — Part 2: Dimensions for bolts and nuts ISO 5855- 2, Metallic materials — Hardness test — Vickers test — Part 1: HV to HV 00 ISO 6507- , Metallic materials — Hardness test — Rockwell test (scales A – B – C – D – E – F – G – H – K) ISO 6508, ISO 7961 , 2) Aerospace — Bolts — Test methods D e finitions manufacturing process These particles may be isolated or arranged in strings 3.4 simp le rando m samp ling the taking of n items from a population of N items in such a way that all possible combinations of n items have the same probability of being chosen 3) 3.5 critical de fe ct a defect that, according to j udgement and experience, is likely to result in hazardous or unsafe conditions for individuals using, maintaining or depending upon the considered product, or that is likely to prevent performance of the function of a maj or end item 3) 3.6 3.1 maj or d e fe ct p ro ducti on b atch quantity of finished bolts manufactured, using the same process, from a single material cast (single heat of alloy), having the same basic part a defect, other than critical, that is likely to result in a failure or to reduce materially the usability of the considered product for its intended purpose number and diameter, heat- treated together to 3.7 the same specified condition and produced as one mino r d e fe ct 3) continuous run a defect that is not likely to reduce materially the 3.2 usability of the considered product for its intended insp e ction lot quantity of bolts from a single production batch with the same part number which completely defines the bolt purpose, or that is a departure from established specification having little bearing on the effective use or operation of this product 3) 3.8 samp ling p lan D iscontinuitie s 3.3.1 crack a plan according to which one or more samples are taken in order to obtain information and possibly to reach a decision 3) rupture in the material which may extend in any direction and which may be intercrystalline or transcrystalline in character 1) 2) 3) At present at the stage of draft (Revision, in part, of ISO 2859: 974 ) At present at the stage of draft Definition taken from ISO 3534: 977 (ISO 3534 is currently being revised by ISO/TC 69, © BSI 01 - 2000 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy Applications of statistical methods ) BS A 299:1 989 3.9 limiting quality (LQ) Acceptance inspections and tests shall be carried out by the manufacturer, or under his responsibility The manufacturer is responsible for the quality of the bolts manufactured in a sampling plan, a quality level which corresponds to a specified and relatively low probability of acceptance: for the purposes of this 4.2 Qualification inspection and test International Standard, a 10 % probability of conditions acceptance (LQ10) It is the limiting lot quality Qualification inspections and tests (requirements, characteristic that the consumer is willing to accept methods, of bolts) are specified in Table with a4)low probability that a lot of this quality would They shallnumbers be carried out on occur — each type and diameter of bolt, 3.1 — 25 bolts selected from a single inspection lot by acceptable quality level (AQL) simple random sampling a quality level which in a sampling plan corresponds The test programme may possibly be reduced, or the to a specified but relatively high probability of qualification of a bolt be granted, without inspection acceptance or testing: any such decision shall be based on the it is the maximum per cent defective (or the results obtained on similar types and diameters of maximum number of defects per hundred units) bolts provided that the design and manufacturing that, for purposes of sampling inspection, can4) be conditions are identical considered satisfactory as a process average The inspections and tests shall be repeated on any bolt if the manufacturing conditions have changed Quality assurance Table indicates the allocation of bolt specimens for 4.1 General the inspections and tests 4.1 Approval of manufacturers Qualification inspections and tests are summarized in Table The manufacturer shall conform to the quality assurance and approval procedures in effect in the 4.3 Acceptance inspection and test conditions purchaser’s country: the purpose of these Acceptance inspections and tests (requirements, procedures is to ensure that a manufacturer has a methods, numbers of bolts) are specified in Table 1; quality system and the capability for continuous they shall be carried out on each production batch or production of bolts complying with the specified inspection lot Bolts from the batch or lot to be tested quality requirements shall be selected by simple random sampling The granting of an approval of the manufacturer is Each bolt may be submitted to several inspections a function of the Certification Authorities, or their or tests appointed representative, who may be the prime The bolts to be subjected to destructive inspections contractor or tests may be those on which non-destructive 4.1 Qualification of bolts inspections or tests have been carried out The purpose of qualification inspections and tests of If a more stringent inspection is deemed necessary, bolts is to check that the design and manufacturing all or part of the qualification inspections and tests conditions of a bolt allow it to satisfy the may be performed during the acceptance inspection requirements of this International Standard and testing In this case, the number of bolts The granting of qualification of a bolt is a function of submitted to these inspections and tests is the the Certification Authorities in the purchaser’s same as that submitted for qualification inspections country, or their appointed representative, who may and tests be the prime contractor Production batches or inspection lots declared 4.1 Acceptance of bolts unacceptable after the acceptance inspections and tests shall be submitted for re-inspection or The purpose of acceptance inspections and tests re-testing only after all defective units have been of bolts is to check, as simply as possible, using a removed and/or defects have been corrected method which is inexpensive and representative of actual conditions of use, with the uncertainty inherent in statistical sampling, that the bolts satisfy the requirements of this International Standard 4) Definition taken from ISO 3534:1977 (ISO 3534 is currently being revised by ISO/TC 69, Applications of statistical methods.) Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy © BSI 01-2000 BS A 299:1989 Twice the normal samp le s ize s hall b e us ed for Requirements re- ins p ecting or re- testing the attrib utes caus ing initial rej ection; the s ame accep tance level s hall b e us ed The requirements of this International S tandard are given in Tab le and, unles s otherwis e s p ecified, they ap p ly to b olts ready for us e Unless otherwis e Accep tance ins p ections and tests are s ummarized in Tab le sp ecified, the tes t temp erature shall b e the amb ient temp erature Thes e requirements comp lement the requirements of all other standards or sp ecifications referenced in the p roduct standard or in the definition document of the b olt © BS I - 00 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy BS A 99: 989 Tab le — Te chnical re quire me nts and te st me thod s Insp e ctio n and te st C lau se No 5.1 5.2 C haracte risti c Mate rials D ime nsio ns Te chni cal re qui re me nt me tho d In accordance with the product As stated in the standard or definition document material specification In accordance with the Standard gauging requirements of the product standard or definition document 5.3 Manufacturing 5.3.1 Forging Q/A a S amp le siz e Q 22 A Table and Table The heads of the bolts shall be formed by a hot or cold forging process before heat treatment In the case of hot forging, the The equipment used equipment shall be such that an shall be approved adequate temperature is guaranteed throughout the production batch 5.3.2 Heat treatment The forged blanks shall be heat treated to produce the properties required by the product standard or definition document Blanks shall not be hardened more than twice 5.3.3 Machining The amount of material removed See 5.5.1 See 5.5.1 from the bearing surface of the head and the shank of the heat- treated blanks shall be as little as practicable consistent with the removal of surface contamination, production of a smooth surface and maintenance of optimum grain flow around the under- head fillet radius as shown in Figure 5.3.4 Stress-relieving After grinding and before thread and fillet rolling, bolts shall be stress- relieved at a temperature higher than 90 ° C and 20 to 30 ° C below the final tempering temperature for at least h 5.3.5 Cold rolling The fillet radius shall be cold rolled after heat treatment and machining so as to remove all visual signs of machining and to create superficial cold working; this may cause distortion which shall not exceed the values shown in Figure 2; this requirement is not applicable to fully threaded screws or bolts with a nominal diameter less than MJ5 5.3.6 Threads To be formed by a single rolling process after all heat treatment (e g after hardening, tempering, stress- relieving, etc ) a Q = qualification inspection and test conditions (4 ) A = acceptance inspection and test conditions (4 ) Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy © BSI 01 - 2000 BS A 99: 989 Tab le — Te chnical re quire me nts and te st me thod s C lause No 5.3.7 C haracte ri stic Surface roughness Insp e cti o n and te st Te chnical re qu i re me nt me tho d In accordance with the p roduct s tandard Vis ual comp aris on or definition document method or Q/A S amp le si z e Q A Tab le thumb nail comp aris on 5.3.8 Surface coating and Tab le method In accordance with the p roduct s tandard S ee ap p licab le or definition document coating Q A Tab le s p ecification and Tab le 5.4 Me chanical p rop e rtie s 5.4.1 Tensile strength In accordance with the minimum tens ile S ee IS O 961 loads s p ecified in Tab le Q A Tab le , In the event of the b olt grip length b eing column B shorter than twice the nominal s hank or Tab le 1 diameter, this tes t shall b e rep laced b y a 5.4.2 Double shear strength hardnes s tes t In accordance with the values s p ecified S ee IS O 961 Q Before surface coating is ap p lied, the S ee IS O 65 - Q hardnes s at the end of the thread s hall b e and I S O 65 08 A Tab le , in Tab le In the event of the b olt grip length b eing shorter than twice the nominal s hank diameter, this tes t shall b e rep laced b y a 5.4.3 Hardness hardnes s tes t Rockwell: /43 H RC 5.4.4 Tension fatigue strength column A or Vickers : 80/43 H V Life: S ee IS O 961 — mean value 65 0 cycles — individual value 45 0 cycles Q 10 A Tab le , column B 000 cycles max Frequency: Loads : 40 H z s ee Tab le Unb roken b olts s hall b e rendered unusab le These requirements are only ap p licab le to b olts with diameters greater than MJ and with a grip length greater than twice 5.4.5 Stress durability the diameter In accordance with the load values sp ecified in Tab le for h E ach cas t of shall b e destroyed Q A S ee note and material b y diameter to b e tes ted S ee I S O 61 Bolts that have b een sub j ected to this tes t 5.5 NO TE Tab le 0, column B Me tallurgical p ro p e rtie s © BS I - 00 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy BS A 99: 989 Tab le — Te chnical re quire me nts and te st me thod s C lause No 5.5.1 C haracte risti c Te chni cal re qui re me nt Insp e cti o n and te st me tho d Head-to-shank Flow lines in the fillet area Specimens shall be taken grain flow and immediately below the from the finished bolt fillet work surface shall closely conform (see Figure 6) The sections effect to the fillet contour to be examined shall be (see Figure ) subj ected to an appropriate See Figure for breaks in the macroscopic etchant flow line Macroscopic examination If there is doubt about the of a longitudinal section at acceptability of the grain flow a suitable magnification or fillet work effect, the (X1 to X20) Q/A S amp le siz e Q A Table 0, column B acceptability shall be decided by the results of the acceptance fatigue test 5.5.2 Thread grain The grain flow shall be flow and work continuous and shall follow effect the general thread contour Macroscopic examination Q A Table 0, column B with the maximum density at the bottom of the root radius (see Figure 3) 5.5.3 Microstructure The finished bolts shall show Specimens shall be taken no signs of overheating, from the finished bolt decarburization, (see Figure 6) The sections carburization, nitrogenization to be examined shall be or intergranular oxidation in subj ected to an appropriate excess of the limits specified microscopic etchant in Table Microscopic examination at Q A Table 0, column B a magnification of X1 00 In cases of doubt, micro- hardness testing of the shank shall be carried out using a load of 50 g Bolts are acceptable if the difference in Vickers micro- hardness, when measured in a zone between 0, 075 and , mm from the surface, is within 45 points 5.5.4 Discontinuities The bolts shall not show any Magnetic inspection by discontinuity equal to or both longitudinal and greater than the limitations circular methods The specified in this International combined method is Standard (see Table 4) Care permissible shall be exercised to avoid In cases of doubt, confusing cracks with other microscopic examination at discontinuities a magnification of X1 00 Cracked bolts and those shall be carried out having discontinuities Q 25 A Magnetic: Table and Table Microscopic examination: Table 0, column B transverse to the axis (i e at an angle of more than ° to the longitudinal axis) shall be rej ected and destroyed Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy © BSI 01 - 2000 BS A 99: 989 Tab le — Te chnical re quire me nts and te st me thod s C lau se No 5.5.4.1 5.5.4.2 5.5.5 5.6 C haracte ri sti c Te chni cal re qu i re me nt Insp e cti o n and te st me tho d Q/A S amp le si z e Head and shank See Table for limits of Thread Grinding burns Prod uct ide ntification acceptance Acceptance limits (see Figure and Figure 5): — in the unloaded part of the fillet, above the pitch diameter, see Table 7; — at the crest of the threads, see Table — values to be increased by half the difference between the actual measured diameter and the minimum external thread diameter (see ISO 5855-2); — a slight irregularity in the form of the crests in relation to the basic profile is acceptable (see Figure 5) Before coating, the bolts shall See ISO 7961 show no signs of grinding burns Q A Table 10, column A 25 Marking in accordance with Visual inspection the product standard or definition document Bolts to be “package-marked” shall be packed and identified in accordance with and Q A Table and Table The bolts shall be packed in Visual inspection such a way as to prevent any damage or corrosion occurring in the course of handling, transportation and storage Each basic package shall only contain bolts with the same part number and the same inspection lot number Each basic package shall Visual inspection carry a label on which the complete part number, quantity, production batch number and inspector’s stamp have been legibly recorded A 100 % A 100 % 5.7 7.1 7.2 D e live ry Packaging Labelling © BSI 01-2000 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy BS A 299:1 989 Table — Qualification testing requirements for bolt samples Bolt sample number Type of test Defined in 10 11 12 Uncoated 13 14 15 16 17 18 19 20 21 22 23 24 25 C oated Non-destructive D imensions Surface roughness × × × × × × × × × × × × × × × × × × × × × × 5.2 5.3.7 × × × × × × Surface coating 5.3.8 D iscontinuities 5.5.4 × × × × × × × × × × × × × × × × × × × × × × × × × 5.6 × × × × × × × × × × × × × × × × × × × × × × × × × Product identification Destructive Tensile strength D oub le shear strength Hardness Tension fatigue strength Stress durability × × × × × 5.4.1 5.4.2 × × × × × × × × × 5.4.3 × × × × × × × × × × 5.4.4 × × × 5.4.5 Head- to- shank 5.5.1 × × × × 5.5.2 × × × × Microstructure 5.5.3 × × × × Grinding burns 5.5.5 grain flow and fillet work effect Thread grain flow and work effect Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy ì ì ì â BSI 01 - 000 BS A 99: 989 Tab le — S ummary of qualification and acce p tance te sts S amp le si z e fo r Typ e o f te st D e fi ne d in Dimensions Surface roughness Surface coating Tensile strength Double shear strength Hardness Tension fatigue strength Stress durability Head-to-shank grain flow and fillet work effect Thread grain flow and work effect Microstructure Discontinuities 5.2 5.3.7 5.3.8 5.4.1 5.4.2 5.4.3 5.4.4 5.4.5 5.5.1 5.5.2 5.5.3 5.5.4 Grinding burns Product identification Packaging Labelling 5.5.5 5.6 7.1 7.2 a qu alificatio n 22 3 5 10 4 25 25 — — te sts acce p tance te sts Table and Table Table and Table Table and Table Table 10, column B or Table 11 — Table 10, column A Table 10, column B Table 10, column B Table 10, column B Table 10, column B Table 10, column B Magnetic: Table and Table Microscopic examination: Table 10, column B Table 10, column A Table and Table 100 % 100 % a The same test sample may be used for more than one test provided that none of the characteristics of the sample is altered during the test procedure Tab le — S urface discontinuitie s and contamination Dimensions in millimetres Maxi mu m d e p th no rmal to su rface fo r b o lts having a Lo catio n Pe rmissib le d isco ntinu ity no mi nal d iame te r u p to mm Heat-to-shank fillet and root of thread Shank diameter and bearing surface of head Non-bearing surface of head Any other location © BSI 01-2000 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy No discontinuities No surface contamination Seams not extending into head-to-shank 0,12 fillet or root of thread No surface contamination Laps, seams and inclusions 0,25 Decarburization — partial 0,1 — total Decarburization — partial 0,1 — total mm and ab o ve 0,15 0,3 0,1 0,2 BS A 99:1 989 Tab le — Minimum te nsile, doub le she ar and stress durab ility loads for qualification and acce p tance te sts Thre ad Te nsile stre ngth te st D iame te r 10 12 14 16 18 20 22 24 Load kN Pitch mm mm 0,7 0,8 1 1,25 1,25 1,5 1,5 1,5 1,5 1,5 11,9 19,12 27,19 38,67 52,1 81,4 121,4 164,5 219,5 282,4 353,2 431,8 502,1 C ross-se ctional are a mm 9,517 15,296 21,753 30,93 41,682 65,136 97,128 131,562 175,613 225,949 282,571 345,478 401,68 D oub le she ar stre ngth te st Load kN 18,85 29,45 42,4 57,7 75,4 118 170 231 302 382 471 570 678 C ross-se ctional are a mm2 12,566 19,635 28,274 38,484 50,265 78,54 113,1 153,9 201,1 254,5 314,2 380,1 452,4 a The cross-sectional area for the stress durability shall be the same as for the tensile strength test S tre ss durab ility te st a Load kN 8,99 14,55 20,56 29,23 39,4 61,6 91,8 124,3 166 213,5 267 326,5 379,6 Tab le — Qualification and accep tance value s for tension fatigue test Thre ad D iame te r mm 10 12 14 16 18 20 22 24 H igh load ±2% Low load kN kN Pitch 0,8 1 1,25 1,25 1,5 1,5 1,5 1,5 1,5 mm 8,8 12,5 17,8 24 37,4 55,8 75,7 101 129,9 162,5 198,6 231 ±2% 0,88 1,25 1,78 2,4 3,74 5,6 7,6 10,1 13 16,3 19,9 23,1 Tab le — Thre ad discontinuities — Maximum dep th of p ermissib le faults (see 5.5.4.2 ) Dimensions in millimetres Thre ad p itch 0,5 0,7 0,8 1,25 1,5 10 0,06 0,08 0,09 0,12 0,15 0,18 0,24 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy D e p th © BSI 01-2000 BS A 299:1 989 Table — Classification of defects Category of defect Acceptable quality level (AQL) Major “A” 0,065 % Major “B” 1% Minor “A” 2,5 % Minor “B” 4% © BSI 01-2000 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy Characteristics Magnetic flaw detection Thread size Shank diameter Grip length Fillet radius: distortion and dimensions Drilled holes missing when required Surface roughness (visual) Burrs and tool marks Surface coating Identification Depth or lightening hole in head Thread form Incomplete threads Squareness between head-bearing surface and shank Straightness of shank Overall length Head diameter Lightening hole diameter Drilled hole location and diameter Wrenching configuration Concentricity of head and shank Coaxiality of shank and thread pitch diameter Chamfer on thread end Hexagon head: chamfer and washer face Collar height Head height 11 BS A 299:1989 Table — Sampling plans for visual inspection and inspection of dimensional characteristics Production batch size 91 to 91 to 151 to 281 to 501 to 201 to 201 to 10 001 to 35 001 to 150 001 to Acceptance number (Ac) and limiting quality (LQ10) in accordance with the acceptance quality level (AQL) AQL 0,065 % AQL % AQL 2,5 % AQL % LQ10 LQ10 LQ10 LQ10 Ac Ac Ac Ac % % % % Sample size 150 150 280 500 200 200 10 000 35 000 150 000 500 000 13 20 32 50 80 125 200 315 500 800 — — 16 G G G G G G G G G G G E G G G E 10 — 1,2 G 0,49 E 7,6 6,5 5,4 4,6 3,7 3,1 — — 10 14 21 — — 18 16 13 11 9,4 7,7 6,4 5,6 — — 10 14 21 — 25 20 18 14 12 10 — — E E Use the sampling plan above (sample size and Ac) Use the sampling plan below (sample size and Ac) NOTE The data given in Table are based on single sampling plans for a standard inspection, as specified in ISO 2859-1 (Table 2-A and Table 6-A) A 100 % inspection should be performed when the sample size is as large as or larger than the batch size Other sampling plans specified in ISO 2859-1 may be used (double or multiple sampling), but these shall be chosen in such a way as to ensure an equivalent quality level As regards those manufacturers who carry out an inspection during the manufacturing process (inspection on a machine and/or inspection between operations), the sampling plan for the final inspection shall be compiled in such a way that the overall inspection plan shall guarantee an equivalent quality level E G Table 10 — Sampling plans for the inspection of mechanical and metallurgical characteristics Production batch size Up to 500 501 to 200 201 to 35 000 Above 35 000 12 Sample size Non-destructive Destructive tests tests A B 13 20 32 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy 5 Acceptance number 0 0 © BSI 01-2000 BS A 299:1989 Table 11 — Variable sampling for tensile test (alternative method) Production batch size Acceptable quality level approximately AQL % Combined First sample sample Sample size Total Sample number K K a Under 51 51 to 300 301 to 500 First 4 Second 12 First Second 5 10 15 First Second 6 12 18 First 501 to 300 Second 7 14 21 First 301 to 200 Above 200 K r t 2, 42 , 35 — — — , 72 2, 21 0, 89 — — — , 74 2, 22 0, 94 — — — 1,7 2, 32 1,1 — — — , 78 8 2, 48 0, 99 — Second 16 24 — — , 81 First 10 10 2, 34 , 31 — Second 20 30 — — 1,8 Evaluate each sample by tensile test as follows: First sample: Accept if X KS WM – a Rej ect if Take second sample if batch is doubtful; evaluate as follows: Second sample: Accept if X KS WM t – t t Rej ect if X KS – r X KS t – t t < M < M Definition of terms: X K K is the average of a, r and K t X individual values in the first sample; S are coefficients of , which is the best estimate of standard deviation, and are used to determine acceptance or rej ection of the batch represented by the sample; where N CX CX is the number of parts in the first sample, M X ( is the sum of squares of X values, )2 is the square of the sum of X values; is the minimum tensile value according to Table 5; is the average of t X t individual values in the combined samples; where N CX CX t is the number of parts in the combined sample, t ( t is the sum of squares of X t values, )2 is the square of the sum of © BSI 01 - 2000 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy X t values 13 BS A 99: 989 NOTE Cut grain acceptable in the zone defined by specified in the product standard) ] Z dimensions [Z max = R max (where R max is the maximum fillet radius Figure — H e ad structure and grain flow 14 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy (see 5.5.1 ) © BSI 01 - 2000 BS A 99: 989 Dimensions in millimetres A B o lt no minal d iame te r max B C max max 1,5 1,5 1,5 1,5 2, 10 12 2, 0, 03 0, 025 3, 14 3, 16 3, 18 4, 20 4, 22 4, 24 4, Figure — D istortion in fille t are a Figure — Grain flow in thre ad © BSI 01 - 2000 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy (see (see 3.5) 5.5.2 ) 15 BS A 99:1 989 Figure — Non-p ermissib le laps, se ams and surface irre gularities Figure — Pe rmissib le laps, seams and surface irregularitie s 16 Reprodu ced by I H S u n d er l i cen se wi th BSI - U n trol l ed Copy (see (see 5.5 4.2 ) 5.5.4.2) © BSI 01 - 2000

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