SPECIFICATION DOCUMENT FOR ALLOY STEEL …...SPECIFICATION DOCUMENT FOR ALLOY STEEL BOLTS AND SCREWS Table of contents Section 1 Scope Section 2 Threaded fasteners and applicable documents

VSSC:FPS:ASS:2011

DOCUMENT NO. VSSC:FPS:ASS:2011 ISSUE NO: 1 DECEMBER 2011 SECURITY UNRESTRICTED CONTROL UNCONTROLLED

SPECIFICATION DOCUMENT FOR ALLOY

STEEL BOLTS AND SCREWS

Table of contents

Section 1 Scope Section 2 Threaded fasteners and applicable documents

2.1 Introduction 2.2 Types of fasteners 2.3 Classification of fasteners 2.4 Applicable / Reference documents 2.5 Relevant part drawings for design, dimensions

and tolerances

Section 3 Selection of material 3.1 Material classification 3.2 Technical requirements 3.3 Melting route 3.4 Acceptance criteria for raw material 3.5. Confirmatory check requirements 3.6. Material data sheet

Section 4 Manufacturing

4.1 General 4.2 Head forming 4.3 Heat treatment 4.4 Head to shank finishing 4.5 Thread forming 4.6 Shank straightness 4.7 Squareness between head bearing surface and shank 4.8 Surface roughness 4.9 Identification 4.10 Surface coating 4.11 Cleaning 4.12 Surface condition

Section 5 Product testing

5.1 General 5.2 Macro examination 5.3 Micrographic examination 5.4 NDE for discontinuities 5.5 Micro hardness test 5.6 Tensile testing 5.7 Sustained load verification test 5.8 Other tests

Section 6 General requirements

6.1 General 6.2 Manufacture 6.3 Sampling 6.4 Product conformance report 6.5 Packing 6.6 Labeling

6.7 Receipt inspection

Section 7 Quality requirement plan

ANNEX 1 AQL and inspection level ANNEX 2 Sampling requirements ANNEX 3 Standard part drawings

Section 1 ______________________________________________________________

Scope

This document specifies the minimum and essential requirements that must be met in the manufacture and control of aerospace quality bolts and screws for launch vehicle systems with thread diameters 1.6mm up to 50mm.

Section 2 ______________________________________________________________

Threaded Fasteners and Applicable documents 2.1 Introduction

This document defines the minimum requirements for the manufacturing, inspection and quality control of aerospace quality bolts and screws of alloy steel material, for use in temperature up to 2350C, having threads in accordance with ISO metric threads. This document also covers acceptance procedures for fasteners, which are already developed and cleared for production (Operational Phase) and qualification and acceptance procedures for fasteners that are to be developed and taken up for production (Qualification Phase).

2.2 Types of Fasteners

The types of bolts and screws covered in this document are the following:

2.2.1 Hexagon socket head cap bolts 2.2.2 Hexagon socket head cap screws 2.2.3 Hexagon head bolts 2.2.4 Hexagon head screws 2.2.5 Slotted 900 counter sunk head screws 2.2.6 Cruciform, 1200 countersunk head screws 2.2.7 Slotted cheese head screws 2.2.8 Hexagon socket 900 counter sunk head bolts 2.2.9 Hexagon socket 900counter sunk head screws 2.2.10 Cruciform 1200 counter sunk head bolts

2.3 Classification of Fasteners

2.3.1 Fasteners are classified into the following classes as given in Table-1, based on

the Ultimate Tensile Strength of the material used for fastener manufacturing.

Table-1

2.4 Applicable /Reference Documents 2.4.1 NFL

NF L05-220 ISO metric thread profile.

NF L05-224 ISO metric thread tolerances.

Class Ultimate tensile stress (MPa) II 1100 III 1250 IV 1550

2.4.2 MIL

MIL-I-6868 Inspection process, Magnetic particle.

MIL-PRF-46010F Lubricant, solid film, heat cured, corrosion inhibiting. 2.4.3 AFNOR

AFNOR 9160 C / General conditions of acceptance and use of wrought EN 2480 steel used in aeronautical constructions.

2.4.4 SAE-AMS-C-8837 Coating, Cadmium (vacuum deposited). SAE-AMS-QQ-P-416B Plating, Cadmium (Electrodeposited). AMS 2427 Aluminium IVD coating

AMS-2630B Ultrasonic Examination of rods.

2.4.5 ASTM ASTM F568-95 Specification for Tensile test wedge angle.

ASTM E112 Standard test method for determining average grain

size.

ASTM F606 Standard test methods for determining the mechanical properties of externally and internally threaded fasteners, washers and rivets.

ASTM E 1417-95a Standard practices for Liquid penetrant examination.

ASTM E 381 Macro Examination of fastener material. ASTM E 45 Micro Examination of fastener material.

2.4.6 ISO ISO 6506 Metallic materials hardness test- Brinell test. ISO 6508 Metallic materials hardness test- Rockwell test.

ISO 6507/1/2 Metallic materials hardness test- Vickers test.

ISO 3353 Aerospace construction: Rolled-run out & level threads.

ISO 3452 Non destructive testing-Penetrant inspection. ISO 3453 Non destructive testing-Liquid Penetrant Inspection. ISO 6892 Metallic materials- tensile testing at ambient

temperature.

ISO 2859/1 Sampling plan indexed by AQL for lot-by-lot inspection

ISO 3951 Sampling procedures and charts for inspection by

variables for percent non-conforming. ISO 6892 Metallic materials-Tensile testing at ambient

temperatures. ISO 6157/3 Fasteners-surface discontinuities—part 3:Bolts,

screws and studs for special requirements. ISO R468 Surface Roughness. 2.4.7 ESA

ESA PSS-01-746 Issue-1 General requirements for threaded fasteners.

2.4.8 MVIT-LVIG-QCD-02/98 Cadmium plated, MOS2 coated with loctite.

2.5 Relevant part drawings for design, dimensions and tolerances

2.5.1 The design, dimensions and tolerances of the bolts and screws shall conform to the standard part drawings specified below (refer Annexure-3):

Sl. No.

Standard Part No.

Type of fastener

1 LF1152 Hexagon Socket Head Cap Bolts 2 LF1151 Hexagon socket head cap screws 3 FR 1150 Hexagon head bolts 4 FR 1060 Hexagon Head Screws 5 FR 1055 Slotted 900 Counter sunk head screws 6 FR 1050 Cruciform1200 counter sunk head screws 7 FR 1054 Slotted cheese head screws 8 FR 1155 Hexagon socket 900 counter sunk head bolts 9 FR 1051 Hexagon socket 900 counter sunk head screws 10 FR 1156 Cruciform 1200 Counter sunk head bolt

2.5.2 By agreement, minor variations in the design, dimensions and tolerances of the

bolts and screws may be permitted to suit the specifications of the manufacturer.

Section 3 ______________________________________________________________

Selection of material

3.1 Material Classification

The bolts and screws shall be made from alloy steels as per the classification given below. The selection of material shall depend upon the axial tensile stress rating requirements specified in the purchase order and listed in Table-2.

Table 2

Class Tensile stress (MPa) Specification of alloy steel

II 1100 30 NCD 16 III 1250 35 NCD16 IV 1550 E 40 CDV 20

3.2 Technical requirements

Table-3 gives general technical requirements for these raw materials. For detailed

specification please refer to the Material data sheet or AIR 9160C.

Table 3

Class Tensile strength

(MPa)

Property requirements

Material Specification

(Recommended material)

UTS (MPa)

0.2%PS (MPa)

%El

(GL=5.65√S) Impact (J/cm2)

Hardness

II 1100 1080-1230 ≥ 880 ≥10 70 321-360 HB 35 – 39 HRC

30 NCD 16

III 1250 1230-1380 ≥1030 ≥8 50 363-401 HB 39-43 HRC

35 NCD 16

IV 1550 1500-1700 ≥1300 ≥9 40 45-48 HRc E 40 CDV 20

3.3 Melting route

Primary melting shall be through either Induction or Electric furnace followed by secondary refining process either by ESR or VAR as applicable.

Air melted and vacuum degassed material is also acceptable for class III fasteners provided it meets the gas contents as per 3.4.1.1

3.4 Acceptance criteria for material

The raw materials (ingot stage and rod/wire stage) intended for the manufacture of

fasteners shall undergo the following tests and shall meet the acceptance criteria stipulated in the appropriate specification given in the Material data sheet.

3.4.1 Ingot stage 3.4.1.1 Chemical composition

Chemical composition shall meet the applicable material specification given in the Material data sheet. The samples shall be taken at 3 locations (Top, Middle and Bottom) after homogenization/ annealing.

The gas levels shall meet the following requirements:

Gas H2 O2 N2 Acceptance level (ppm) ≤ 2 ≤ 40 ≤ 80

Alternatively one sample at the ingot stage shall be analysed for gas content and two samples shall be analysed during receipt inspection and the values shall meet the acceptance criteria mentioned above.

3.4.1.2 Macro Examination

Macro examination shall be done as per ASTM – E 381, on the entire cross section of the ingots, by taking samples from Top and Bottom of each ingot. The macro structure shall be free from any harmful defects like porosities, segregation, shrinkage, cracks etc. The macro evaluation shall be done after sufficient mechanical working (ingot break down), annealing and discarding the ends.

3.4.2 Rod/ Wire stage 3.4.2.1 The raw materials in the form of rod/ wire shall undergo the following tests and

results shall be acceptable as per the standard specified. The supply condition of rods/ wires shall be in annealed or spheroidised condition. Each lot shall be qualified.

Lot: A lot is defined as material of same cast and produced as one continuous run, free from any interruptions or changes that could result in a variation in the quality of the product.

3.4.1.3 Chemical composition shall meet the applicable specification stipulated in the Material data sheet.

3.4.1.4 Micro examination: Grain size shall be evaluated, as per the standard ASTM – E 112 and the grain size shall be 5 or finer. Alternatively at the fastener stage the grain size shall be ASTM no. 6 or finer. The supply condition shall also be confirmed in microstructure.

Micro examination shall be done as per ASTM – E 45 and the inclusion rating shall be as per the following specification.

Type –A Type – B Type – C Type - D

Thin

Heavy

Thin

Heavy

Thin

Heavy

Thin

Heavy

Acceptance level 1.5 1.0 1.5 1.0 1.5 1.0 1.5 1.0

3.4.1.5 Ultrasonic examination

All the rods shall be 100% ultrasonically examined (either by contact or immersion) at an intermediate stage or at the final stage of the raw material. The acceptance criteria shall be as per AMS – 2630B, Class-A.

3.4.1.6 Mechanical properties:

Hardness: Annealed hardness shall be ensured on the rods/wires.

Material 30 NCD 16 35 NCD 16 40CDV20 Hardness ≤ 270 HB ≤ 295 HB ≤ 235 HV 30

Tensile testing: Though the supply condition is annealed, the mechanical properties shall be proven on the samples heat treated as per the applicable heat treatment cycle given in the data sheet. Three specimens shall be tested for each lot and all the three samples shall meet the appropriate specification requirements given in the data sheet. In case of failures, retest shall be done on double the number of specimens from the same lot and all the specimens shall meet the specification requirements.

In the event of failures in retest, the cause shall be investigated and the samples from the lot shall be re-heat treated if required. If the specimens fail to meet the specification requirements even after re-heat treatment, the lot shall be rejected.

3.5 Confirmatory check requirements 3.5.1 Party shall identify each coil size, heat number and batch number with

manufacturers identification tag and correlate with raw material test certificates. 3.5.2 As a confirmatory check, for wire diameter up to M10, one sample coupon from

beginning of each coil shall be taken, heat treated and tested for (a) Chemical (b) UTS (c) Hardness

3.5.3 For wire diameter M12 and above one sample coupon from beginning of each coil

shall be taken, heat treated and tested for (a) Chemical (b) UTS (c) 0.2% proof stress (d) % Elongation (e) Hardness (f) Impact strength

3.6 Material Data sheets

Material Data Sheet NO: 01

30 NCD 16

Chemistry C Si Mn Cr Ni Mo V W S P Nb Ti 0.26 0.33

0.10 0.40

0.20 0.60

1.20 1.50

3.30 4.30

0.30 0.60

--- --- ≤

0.020

≤

0.025 --- ---

Supply condition Annealed

Heat treatment Cycle Hardening -- 850 ± 10 ºC, Oil quenching. Tempering -- 585 ± 5 ºC.

Mechanical properties (Ø ≤ 40mm) - Hardened and Tempered condition

UTS (MPa) 1080-1230 0.2% PS (MPa) ≥ 880 %El ≥ 10 %RA ≥ 45

Hardness HRC --- HB 321- 360

Impact Strength (J/cm2) ≥ 70 Shear test (MPa) --- Grain size ≥ ASTM 5

Material Data sheet NO: 02

35 NCD 16


0.15 0.40

0.30 0.60

1.60 2.00

3.50 4.20

0.25 0.60

--- --- ≤

0.020

≤

0.025 --- ---


Heat treatment Cycle

Hardening -- 875 ± 10 ºC. Quench media: up to 75mm -Air cooling >75mm - Oil quench Tempering -- 550-580 ± 5 ºC – 3hrs. Air cooling Spheroidising Cycle: Air cooling from 8800C + prolonged soaking at 6500C for 40 hrs + furnace cooling.

Mechanical properties (Ø ≤ 75mm) - Hardened and Tempered condition

UTS (MPa) 1230-1380 0.2% PS (MPa) ≥ 1030 %El ≥ 8 %RA ≥ 40

Hardness HRC 39-43 HB 363- 401

Impact Strength (J/cm2 ) ≥ 50 Shear test (MPa) --- Grain size ≥ ASTM 5

Material Data sheet NO: 03

E 40 CDV 20


0.80 1.00

0.20 0.40

4.75 5.25

--- 1.20 1.40

0.40 0.60

--- ≤

0.010

≤

0.015 --- ---


Heat treatment Cycle

Pre heating --- 620-870ºC / 30min. Hardening --- 1000-1020ºC , Air cooling. Tempering - I --- 545-555ºC / 2hrs. Tempering - II -- 580-620ºC / 2hrs. (Tempering – III -- If necessary).

Mechanical properties - (Ø ≤ 40mm) Hardened and Tempered condition UTS (MPa) 1500-1700 0.2% PS (MPa) ≥ 1300 %El ≥ 9 %RA ≥ 40

Hardness HRC 45 – 48 HV 449 – 495

Shear test (MPa) --- Grain size ≥ ASTM 5

Section 4 ______________________________________________________________

Manufacturing 4.1 General

4.1.1 This section is related to the manufacture of threaded fasteners. The

manufacturer shall have a Quality Assurance System, and in accordance with this, due care shall be taken during all stages of production and fasteners shall be inspected during each step of the manufacturing process. Conformance with the technical requirements of this specification shall be evaluated at all stages of production.

4.2 Head forming 4.2.1 The heads of the Bolts/ Screws shall be formed through cold forging for sizes up to

M12 and a hot or cold forging for size above M12 before heat treatment. The socket on head may be machined or forged.

4.3 Heat treatment 4.3.1 The headed forged blanks shall be heat treated using applicable heat treatment

cycle as per the material specifications to achieve the minimum tensile strength requirements as specified in the standard part drawing.

4.3.2 Before heat treatment, calibration of the furnace, thermocouples and controllers

shall be ensured as per the calibration procedures approved by VSSC. 4.3.3 Headed forged blanks shall be heat treated in a qualified furnace (temperature

uniformity of ± 5°C up to 800°C and ± 10°C above 800°C) to produce required mechanical properties. Production parts shall be heat treated as one batch.

4.3.4 During heat treatment, process cycle shall be ensured. Also three specimens shall be put along with the charge during heat treatment.

4.3.5 After the heat treatment, the following tests shall be conducted on the heat-treated

wires / rods to ensure that the correct heat treatment process is followed. 4.3.6 UTS and hardness for all the specimens for corresponding to fasteners of size up

to M10 4.3.7 UTS, 0.2% proof stress, % Elongation, impact, %reduction in area and hardness

for wire / rod specimens corresponding to fasteners of size M12 and above. 4.3.8 Samples of fasteners M5 or larger shall be tested for hardness on the end opposite

to that of the head after full heat treatment but before head to shank fillet rolling and thread rolling.

4.3.9 If mechanical test results/ retest results as per procedure of any batch do not

conform to requirement specified for the material, re-heat treatment of the batch or blanks should be done. Re-heat treatment of blanks shall not exceed twice.

4.4 Head to shank finishing

4.4.1 After heat treatment, the shank and bearing surface of the head of the blanks may be wet ground such that the amount of metal removal shall be minimum and grain flow around the under head radii is maintained.

4.4.2 The head and the head to shank area shall show continuous grain flow as shown

in Figure-1 .Cut grain lines may exist in the A area of Figure-1 with the maximum permissible values listed in Table-4.

Fig. 1 Head structure and grain flow

Table-4

Nominal Diameter

(mm) (Major

Diameter)

3 4 5 6 7 8 10 12 14 16 18 20 22 24 27 30

Maximum permissible

A value (mm)

0.7 0.8 0.9 1.2 1.2 1.2 1.4 1.6 1.6 2.0 2.0 2.0 2.0 2.0 2.0 2.0

4.4.3 The head to shank fillet radius shall be cold worked (rolling), sufficiently after heat

treatment to remove evidence of machining in the radius area. No machining or etching shall be done on fillet radius after cold working (rolling).

4.4.4 The fillet radius profile shall be smooth and blend into the other surfaces. Cold

working of head to shank fillet may cause distortion of fillet area. 4.4.5 Distortion of the head to shank fillet due to cold working shall not exceed 0.05 mm

above or below the profile lines at points indicated at A and B in Figure-2.

4.4.6 The distorted area shall not extend beyond the dimension C indicated in figure-2 and listed in Table-5.

Fig.2 Head to shank fillet rolling

Table-5

Nominal diameter (mm)

(Major diameter) 3 4 5 to 7 8 to 10 12 to 16 18 to 24 >24

C maximum (mm) 1.00 1.40 1.60 2.40 3.20 4.00 4.80

4.5 Thread forming 4.5.1 Threads shall be formed by one single rolling process after final heat treatment.

Machined threads shall not be permitted. Any attempt to increase the length of an existing thread by either rolling or machining shall be unacceptable.

4.5.2 Thread of large diameter fasteners may be machined oversize and rolled in order

to avoid lap. 4.5.3 The thread profile and tolerances shall conform to ISO metric threads as per

NFL05-220 & NFL05-224 standards. Allowance shall be provided for coatings, so as to maintain the intended fit after coating.

4.5.4 The thread run out portion shall be such as to ensure a progressive and regular

junction with the shank to avoid a step change in section as specified in ISO 3353. 4.5.5 All measurements shall be carried out with calibrated instruments and gauges. 4.6 Shank straightness 4.6.1 The permissible deviation of the straightness of the shank on the total fastener

length is indicated in Figure-3 and listed in Table-6.

Fig. 3 Shank straightness definition

Table 6

Nominal Diameter

(mm)

Permissible maximum straightness deviation of the fastener shank including the threaded portion from the straight per 10 mm fastener length (mm)

3 to 8 0.03 10 to 20 0.025

>20 0.02 4.7 Squareness between head bearing surface and shank 4.7.1 Any out of squareness of head bearing surface, relative to thread axis, shall be

within 0.08mm. 4.8 Surface roughness 4.8.1 The values of surface roughness, before surface coating, shall not exceed the

values listed in Table 7. The surface roughness shall be determined by visual and fingernail comparator method (ISO R468).

4.8.2 In the case of discrepancy, a profilometer shall be used, as far as the surface is

accessible. Table 7

Feature

Roughness Height rating maximum, Ra (µm)

General fasteners

Titanium fasteners

Bearing surface of head 0.8

0.8 Shank Head to shank fillet 0.4 Thread run out Thread root Thread sides Others 3.2 3.2

4.9 Identification

4.9.1 The identification of the fasteners for above M8 shall be marked, on the upper face

or side of the head with depressed characters of rounded root form and not greater than 0.25 mm in depth.

4.9.2 For below M8, fasteners shall be identified with tags as a batch.

4.9.3 Property class and manufacturer shall be indicated in the identification. 4.10 Surface coating 4.10.1 The bolts and screws of class II and III shall be coated with Cadmium in

accordance with SAE-AMS-QQ-P416B, type II, class 2 specification. Such

fasteners shall be hydrogen relieved after plating at 190°C for 23 hours minimum. Salt spray test as periodic test to be done only after a time gap of 24 hrs after the coating process. Alternatively the fasteners shall be coated with ion vapour deposition of Aluminium in accordance with AMS 2427 & MOS2 coated as per MIL-PRF-46010F.

4.10.2 The bolts and screws of class IV shall be coated by vacuum deposition of

Cadmium in accordance with SAE-AMS-C-8837, type II, class 3 specification or ion vapour deposition of Aluminium in accordance with AMS 2427 & MOS2 coated as per MIL-PRF-46010F.

4.10.3 Coating thickness shall be inspected by gauging or by putting specimens. In case

of any dispute micrographic examination can be resorted to. 4.10.4 If called for, the fasteners shall be provided with additional coating of molybdenum

disulfide dry film lubricant in accordance with MIL-PRF-46010F specification. 4.11 Cleaning 4.11.1 The fasteners shall be clean, free of oxides and metal contaminants. 4.12 Surface condition 4.12.1 The fasteners shall be free from burrs, tool marks, scales and seams.

Section 5 ______________________________________________________________

Product testing 5.1 General

5.1.1 This section deals with Product testing methods such as Macro, Micro, NDE, Micro

hardness, Tensile testing, sustained load verification test and other tests etc that are essential for product qualification.

5.2 Macro Examination

5.2.1 Macro examination (on samples) shall be carried out to cover the entire

longitudinal cross section of the fastener (head through thread axis) and the samples shall be examined at 10X or greater magnification. Flow lines in the head to shank fillet shall be smooth and blend in to the other surface. The grain flow in the threads shall be continuous and follow the thread contour with maximum density at the bottom of root radius shown in Fig- 4. at 50X magnification.

Fig. 4 Grain flow in thread

5.2.2. Metallurgical specimens shall be taken from the finished bolts/screws as shown in

Fig.5.

Fig. 5 Metallurgical specimen

5.3 Micro Examination

5.3.1 The samples made as above shall be examined at X100 magnification.

5.3.2 The microstructure shall be free from voids, inclusions, cracks or gross alloy segregation. The fasteners shall not show signs of oxidation, carburisation, and surface decarburisation as well as presence of untempered martensite.

5.3.3 The grain size shall be uniform and have index ≥6 as per ASTM E112. 5.4 NDE for discontinuities

5.4.1 Selected samples of the fasteners prior to any surface treatment shall be subjected

to fluorescent liquid penetrant or magnetic particle inspection (according to ISO 3452/ 3453 or ASTM E1417-95a and MIL-I-6868 respectively). Inspection results shall be evaluated according to ISO 6157/3 (with exception of annexure).

5.4.2 The finished bolts/screws shall be magnetically inspected by both longitudinal and

circular methods. The combined method is permissible.

5.4.3 Parts showing indications, which are considered cause for rejection, will be subjected to micro examination at a suitable magnification (100X).

5.4.4 The limits of acceptance for seams and inclusions are given in Table-8 and Fig.6, 7

and 8. Cracks are not permitted. Bolts/screws having discontinuities transverse to axis (ie. at an angle of more than 100 to the longitudinal axis) shall be rejected.

Table 8

Surface discontinuities and contamination

Location Permissible discontinuities Maximum depth normal to surface

Bolt/screw nominal diameter Up to 16 mm 18 mm and above

Head-to-shank fillet, root of threads

No discontinuities and no surface contamination

0.00 0.00

Shank diameter and bearing surface of head

Seams not extending into head to shank fillet or root of threads

0.12 0.15

Non-bearing surface of head (surface of head

not in contact with any other surface)

Laps, seams and inclusions 0.25 0.30

Any location Complete or partial

decarburisation 0.10 0.20

Note: Depth of defect equals 20% of basic thread depth plus ½ the difference of actual diameter and minimum major diameter.

Fig. 6 Crest lap imperfections

Fig.7 Non permissible laps, seams and surface irregularities.

Fig.8 Permissible laps, seams and surface irregularities.

5.4.5 Faults with depth 20% of the basic thread height (Table-9) are permissible on the

thread crest and on that part on the non-loaded flank, which is situated above the pitch diameter.

5.4.6 Slight deviation from the thread contour is permissible at the crest of the threads as shown in the Fig.6.

Table 9

Thread discontinuities– maximum depth of permissible faults Thread pitch Depth (mm)

(20% of basic thread depth) 0.5 0.06 0.7 0.08 0.8 0.09 1.0 0.12 1.25 0.15 1.50 0.18 2.00 0.24

5.4.7 NDE shall be performed by inspectors qualified to ASNT level-II or equivalent. 5.5 Micro hardness test (For class III & IV fasteners only) 5.5.1 Micro hardness test of the cross section of the bolts/ screws shall be used to check

for correct heat treatment, excessive decarburisation or recarburisation. Hardness reading at the core and at 0.13 mm from the surface shall be within the limits specified in the applicable material standard. Alternatively estimation of Decarburization layer by metallographic methods are also acceptable.

5.5.2 Knoop micro hardness reading with a one (1) Newton force shall be taken on a

cross section of bolts/screws used for metallurgical examination. Difference between the micro hardness reading at 0.13 mm and the readings at 0.03, 0.05, 0.08 mm from the surface shall not exceed forty (40) points on any one specimen.

5.5.3 Micro hardness reading shall not be taken adjacent to the exterior wrenching surface of the bolts/screws.

5.6 Tensile testing

5.6.1 Proof load testing : Samples of fasteners shall be proof tested to 75% for the minimum tensile load given in Table 10,10.1 and 10.2. Proof load testing shall be according to ASTM F606. Load to be retained for 15 sec. and gauge check or length measurement shall be done after testing.

5.6.2 Samples of fasteners shall be tensile tested in fully finished form, if a protruding head with a grip length ≥ the value specified in the table given below. Countersunk head fasteners with overall length ≥ three times the nominal diameter or with a minimum length of 18mm also shall be tensile tested.

M3 M4 M5 M6 M8 M10 M12 M14 M16 M18 M20 M27 M30

10 12 12 14 20 25 30 35 40 45 45 2.5D 2.5D

5.6.3 The fracture of fasteners during tensile test shall occur only in the shank or thread

for the protruding head fasteners. Failure in the head to shank fillet is a nonconformance.

5.6.4 Tensile testing shall be according to ISO 6892 and shall meet specified Ultimate

tensile load = UTS X [π/4 X ((d2+d3)/2) 2] where d2 and d3 are the nominal pitch and minor diameters respectively.

5.6.5 The finished bolts/screws shall develop the minimum tensile loads specified in

Table-10, Table 11 and Table 12. Table 10

Minimum Tensile load (Class II-1100 Mpa)

Thread Diameter

Pitch

Tension Cross section (mm2)

Minimum Tensile load at Proof load at

Protruding head (KN)

Counter sunk head (KN)



3 0.5 5.03 5.5 4.4 4.13 3.3 4 0.7 8.78 9.7 7.7 7.23 5.78 5 0.8 14.20 15.6 12.5 11.7 9.38 6 1.0 20.10 22.1 17.7 16.58 13.28 8 1.0 39.2 43.1 34.5 32.33 25.88 10 1.25 61.6 67.8 54.2 50.85 40.65 12 1.25 92.1 101.3 81.0 75.98 60.75 16 1.50 167.00 183.7 147.0 137.78 110.25 20 1.50 272.00 299.2 239.4 224.4 179.55 24 2.00 284.00 422.4 337.59 316.8 253.19 27 2.00 496.00 545.60 436.5 409.2 327.38

Table 11 Minimum Tensile load (Class III-1250 Mpa)

Thread Diameter

Pitch







3 0.5 5.03 6.3 5.0 4.73 3.75 4 0.7 8.78 11.0 8.8 8.25 6.6 5 0.8 14.20 17.8 14.2 13.35 10.65 6 1.0 20.10 25.1 20.1 18.83 15.08 8 1.0 39.20 49.0 39.2 36.75 29.4 10 1.25 61.60 77.0 61.6 57.75 46.2 12 1.25 92.10 115.1 92.1 86.33 69.08 16 1.50 167.0 208.2 167.0 156.15 125.25 20 1.50 272.0 340.0 272.0 255 204 24 2.0 384.0 480.0 384.0 360 288 27 2.0 496.0 620.0 496.0 465 372 30 2.0 621.20 776.49 621.20 582.37 465.90

Table 12

Minimum Tensile load (Class IV-1550 Mpa)

Thread Diameter

Pitch







3 0.5 5.03 7.8. 6.2 5.85 4.65 4 0.7 8.78 13.6 10.9 10.2 8.18 5 0.8 14.20 22.0 17.6 16.5 13.2 6 1.0 20.10 31.2 24.9 23.4 18.68 8 1.0 39.20 60.8 48.6 45.6 36.45 10 1.25 61.60 95.5 76.4 71.63 57.3 12 1.25 92.10 142.8 114.2 107.1 85.65 16 1.50 167.0 258.9 207.0 194.18 155.2 20 1.50 272.0 421.6 337.3 316.2 252.98 24 2.0 384.0 595.2 476.2 446.4 357.15 27 2.0 496.0 768.8 615.0 576.6 461.25

5.6.6 Loading shall be parallel to fastener axis. At least two complete threads shall be

kept not engaged in the threaded part of the jig. Speed of crosshead movement shall not exceed 25mm/ minute and test shall not be completed in <15s.

5.6.7 Product level testing to be done on all fasteners meeting the length requirement as per clause 5.6.2

5.7 Sustained load verification test / Wedge torque test 5.7.1 Wedge torque test to be done for all batches of fasteners. Wherever length is not

sufficient, sustained load test to be done.

5.7.2 Samples of fastener shall be lubricated with Molybdenum disulfide and tightened on a part with demonstrated hardness at least 45HRC to a torque T = 0.10 X D X F

where D is the nominal diameter of fastener, and F = 0.75 X UTS X [π/4 X ((d2+d3)/2) 2] where d2 and d3 are the nominal pitch and minor diameters respectively. The fastener shall sustain the load for 24 hours.

5.7.3 Fastener tested shall be acceptable in DP or Fluorescent penetrant test as per ISO 6157/3 before and after sustained load test.

5.8 Other tests

5.8.1 Any other tests to be done if specified by designer.

Section 6

______________________________________________________

General requirements 6.1 General

6.1.1 This section deals with the general requirements; sampling, product conformance

report, packing and labeling that are to be implemented by the manufacturer during the manufacturing stage and at the final qualification stage of the fasteners.

6.2 Manufacture 6.2.1 The manufacturer shall have all the facilities required for the realization, inspection

and testing of the fasteners.

6.2.2 Any subcontracting of the work if resorted to, shall be after thorough evaluation of

the party’s capability and approval. Inspection, quality control and testing at the subcontractor’s end shall be carried out by the manufacturer or independent reputed third party agencies under the responsibility of the manufacturer.

6.2.3 The manufacturer shall have an independent inspection and quality control system within the company.

6.2.4 The manufacturing of fasteners shall be as per an approved manufacturing process and quality control plan.

6.2.5 The manufacturer of fastener shall certify the compliance with QA requirements specified by VSSC. In the case of indigenous fasteners, VSSC representative shall provide surveillance during critical stage inspection identified in the QC plan. Imported fasteners shall be certified by reputed third party agencies after witnessing testing at manufacturer’s site.

6.2.6 The dies for thread rolling shall be qualified dimensionally for thread profile prior to

starting production.

6.2.7 Qualification of a trial batch of fasteners shall be done prior to starting production

of fasteners with a new thread size. 6.3 Sampling

6.3.1 Random samples shall be taken from a batch of fasteners wherever sampling tests

are called for. A batch of fastener may be considered as those fasteners of the same size and diameter, fabricated by the same process from material of same heat, heat treated as one batch and processed and produced as one continuous run. If cadmium plating batch size is lower than the heat treatment batch size, samples shall be drawn representing all cadmium plating batches meeting the total sampling quantity requirements.

6.3.2 Sampling shall be as per ISO standards 2859/1 and 3951.The AQL, inspection

level and sampling requirements for different features are given in Annexure 1 & 2.

6.3.3 Fasteners under development shall be inspected under tightening inspection category.

6.3.4 Any batch found nonconforming, for dimensional features with AQL 1.5% and

above can be resubmitted. Resubmission shall be only after 100% inspection. Such fasteners shall be separately identified as a resubmitted batch indicating the reason for original rejection.

6.3.5 Results of resubmitted batches shall be recorded separately from the records of

batches offered for original inspection.

6.4 Product conformance report

6.4.1 Each batch of fasteners shall be supplied with a Product Conformance Report, which shall contain the following minimum details: raw material supplier’s name, raw material test certificate, date of manufacturing, purchase order, batch identification, specification reference, mechanical properties, other inspection and test results.

6.5 Packing

6.5.1 The bolts/screws shall be packed in such a way so as to prevent any damage or

corrosion occurring in the course of handling, transportation and storage. 6.5.2 Each basic package shall only contain bolts/screws with the same part number and

the same lot number. 6.5.3 Each batch/lot shall be packed in sealed polythene bag/containers in order to avoid

moisture and corrosion. 6.5.4 The external thread of the fasteners for M8 and above shall be covered with plastic

sheath to avoid thread damage. 6.5.5 Each individual package of fasteners shall be provided with the outside marking

ensuring traceability 6.6 Labeling

6.6.1 Each basic package shall carry a label on which manufacturer’s name, trade mark,

the complete part number, quantity, the lot number and inspection acceptance shall be legibly marked.

6.6.2 An assortment of unit packages may be packed in large cartons. Cartons shall bear

appropriate designation of items quantity, manufacturers trademark, purchase order reference etc. Package shall meet commercial handling requirements.

6.7 Receipt inspection

6.7.1 All fasteners received at VSSC shall be verified for compliance to the Product

conformance record by physically verifying the crates for identification. QC shall verify the results provided in the Product Conformance Record for adequacy and compliance to the specification.

6.7.2 Inspection shall be repeated after receipt at VSSC for all fasteners realized without

direct surveillance by VSSC, on sampling basis. Receipt inspection shall cover gauging for dimensions, identification on fastener head, chemical test to verify type of material, tensile test, hardness test, sustained load verification test (for M8 and above), thickness of plating or coating and visual inspection.

6.7.3 Number of samples shall be that for reduced inspection at same initial AQL level,

except for tensile and sustained load tests. Normal inspection level S2 with AQL 2.5% shall be used for tensile and sustained load tests.

6.7.4 After inward inspection, tested samples shall be disposed and remaining accepted

fasteners shall be placed in a separate cover with identification tag of the following details:

Size & property class, batch no., quantity supplied, quantity available, date of fastener receipt and receipt inspection date.

Section7 ______________________________________________________________

Quality Requirement plan

Details of Qualification / Acceptance tests required

Category

Imported Fasteners

Imported material and Indigenous

manufacture

Indigenous material and manufacture

Ingot stage

Chemical composition & Gas content

Verify Manufacturer’s Test Certificate.


��

Macrostructure --- -- ��

Rod/ wire stage

Chemical composition


��

Macrostructure -- �� Microstructure – Grain

size and Inclusion rating

-- ��

Ultrasonic test -- �� Mechanical properties on samples (Tensile,

Impact and Hardness) ��

Fastener stage

Macro of longitudinal section


��

Microstructure-Inclusion rating & Decarburisation

��

Mechanical properties on fastener samples (Tensile, Impact and

Hardness)

��

Magnetic particle test ��

Dimensional inspection ��

D.P.Test ��

Inward inspection

after receipt – As per

sampling plan

Dimensional �

Ensure traceability w.r.t test certificate.

Ensure traceability w.r.t test certificate.

Chemical composition �

Mechanical properties (Tensile, Impact and

Hardness) �

Microstructure-Inclusion rating

�

Macro – Flow lines �

Annexure 1

AQL and inspection levels

Feature AQL Inspection level Sampling plan

Hardness after heat treatment 0.65% Normal inspection, level II

ISO 2859

Workmanship

Identification 2.5%

Normal inspection, level II

ISO 2859

Surface roughness

2.5% Scale & excessive seam Burrs & tool marks

4%

Dimensional inspection

Thread size 0.65%

Shank diameter Head to shank fillet

1% Thread run out Plain shank length Overall length

1.5%

Head angle & bearing surface for counter sunk head Head bearing surface Squareness of head bearing surface to shank

1.5%

Concentricity of head shank to thread shank Location, diameter & depth of driving feature

2.5%

Straightness of shank Head geometry Thread chamfer

4% Other dimensions

Macro & micrography 2.5% Normal inspection, level S2

ISO 2859

Micro hardness on section 2.5% Normal inspection, level S2

ISO 2859

Tensile test 1%

Normal inspection, level I, ‘s’ method for min. & max. UTS

ISO 3951

Sustained load test 2.5% Normal inspection level S1

ISO 2859

NDE 0.065% Normal inspection, level II

ISO 2859

Coating thickness 2.5% Normal inspection, level II

ISO 2859

SAMPLING REQUIREMENTS Annexure 2 Code Letters:

Lot or batch size Inspection level

S1 S2 II

2 to 8

A A A

9 to 15

A A B

16 to 25

A A C

26 to 50

A B D

51 to 90

B B E

91 to 150

B B F

151 to 280

B C G

281 to 500

B C H

501 to 1200

C C J

1201 to 3200

C D K

3201 to 10000

C D L

10001 to 35000

C D M

35001 to 150000

D E N

150001 to 500000

D E P

500001 to over

D E Q

Single Sampling Plan for Normal Inspection Sample size code letter

Sample size Acceptable Quality level (Normal inspection) 0.065 0.65 1 1.5 2.5 4

AC RC AC RC AC RC AC RC AC RC AC RC

A B C

2

0 1

0 1

0 1

0 1

0 1

3

5

D E F

8

0 1

1 2

1 2 2 3

13

20

G H J

32

1 2

1 2 2 3

1 2 2 3 3 4

2 3 3 4 5 6

3 4 5 6 7 8

50

80

K L M

125

2 3

3 4

5 6

3 4 5 6 7 8

5 6 7 8

10 11

7 8

10 11

14 15

10 11

14 15

21 22

200

315

N P Q

500

1 2 2 3

7 8

10 11 14 15

10 11 14 15 21 22

14 15 21 22

21 22

800

1250

R

2000 3 4 21 22

= Use first sampling plan below arrow. If sample size equals or exceeds, lot or batch size, carry out 100% inspection.

= Use first sampling plan above arrow.

Single Sampling Plan for Tightened Inspection Sample size code letter

Sample size Acceptable Quality level (Tightened inspection) 0.065 0.65 1 1.5 2.5 4


A B C

2

0 1

0 1 1 2 2 3

0 1

3

5

D E F

8

0 1

1 2

13

20

G H J

32

0 1

1 2

1 2 2 3 3 4

2 3 3 4 5 6

50

80

K L M

125

1 2 2 3

3 4

2 3 3 4 5 6

3 4 5 6

8 9

5 6

8 9 12 13

8 9 12 13 18 19

200

315

0 1

N P Q

500

1 2

5 6

8 9 12 13

8 9 12 13 18 19

12 13 18 19

18 19

800

1250

R S

2000

3150

2 3 18 19

= Use first sampling plan below arrow. If sample size equals or exceeds, lot or batch size, carry out 100% inspection. = Use first sampling plan above arrow.

Single Sampling Plan for Reduced Inspection Sample size code letter

Sample size Acceptable Quality level (Reduced inspection) 0.065 0.65 1 1.5 2.5 4


A B C

2

2

2

0 1

0 1

0 1

0 1

0 1

D E F

3

5

8

0 1

0 2

0 2 1 3

G H J

13

20

32

0 2

0 2 1 3

0 2 1 3 1 4

1 3

1 4

2 5

1 4 2 5 3 6

K L M

50

80

125

1 3

1 4 2 5

1 4 2 5 3 6

2 5 3 6

5 8

3 6

5 8

7 10

5 8 7 10

10 13

N P Q

200

315

500

0 2 1 3

3 6

5 8 7 10

5 8

7 10

10 13

7 10 10 13

10 13

R

800 1 4 10 13

= Use first sampling plan below arrow. If sample size equals or exceeds, lot or batch size, carry out 100% inspection. = Use first sampling plan above arrow; If Ac has been exceeded, but RC has not been reached, accept the lot, but

revert to normal inspection.

Double sampling plan for normal inspection Sample

size code letter

Sample Sample size

Cumulative sample

size

Acceptable quality level (normal inspection) 0.065 0.65 1.0 1.5 2.5 4.0

Ac Rc Ac Rc Ac Rc Ac Rc Ac Rc Ac Rc

A

B First Second

2 2

2 4

*

C First Second

3 3

3 6

*

D First Second

5 5

5 10

*

E First Second

8 8

8 16

* 0 2 1 2

F First Second

13 13

13 26

* 0 2

1 2 0 3 3 4

G First Second

20 20

20 40

0 2 1 2

0 3 3 4

1 4 4 5

H First Second

32 32

32 64

0 2 1 2

0 3 3 4

1 4 4 5

2 5 6 7

J First Second

50 50

50 100

0 2 1 2

0 3 3 4

1 4 4 5

2 5 6 7

3 7 8 9

K First Second

80 80

80 160

0 3 3 4

1 4 4 5

2 5 6 7

3 7 8 9

5 9 12 13

L First Second

125 125

125 250

* 1 4 4 5

2 5 6 7

3 7 8 9

5 9 12 13

7 11 18 19

M First Second

200 200

200 400

2 5 6 7

3 7 8 9

5 9 12 13

7 11 18 19

11 16 26 27

N First Second

315 315

315 630

3 7 8 9

5 9 12 13

7 11 18 19

11 16 26 27

P First Second

500 500

500 1000

0 2 1 2

5 9 12 13

7 11 18 19

11 16 26 27

Q First Second

800 800

800 1600

0 3 3 4

7 11 18 19

11 16 26 27

R First Second

1250 1250

1250 2500

0 4 4 5

11 16 26 27

Double sampling plan for tightened inspection Sample

size code letter

Sample Sample size

Cumulative sample

size

Acceptable quality level (tightened inspection) 0.065 0.65 1.0 1.5 2.5 4.0


A

B First Second

2 2

2 4

C First Second

3 3

3 6

*

D First Second

5 5

5 10

*

E First Second

8 8

8 16

*

F First Second

13 13

13 26

* 0 2

1 2 G First

Second 20 20

20 40

* 0 2

1 2 0 3 3 4

H First Second

32 32

32 64

0 2 1 2

0 3 3 4

1 4 4 5

J First Second

50 50

50 100

0 2 1 2

0 3 3 4

1 4 4 5

2 5 6 7

K First Second

80 80

80 160

0 2 1 2

0 3 3 4

1 4 4 5

2 5 6 7

3 7 11 12

L First Second

125 125

125 250

0 3 3 4

1 4 4 5

2 5 6 7

3 7 11 12

6 10 15 16

M First Second

200 200

200 400

* 1 4 4 5

2 5 6 7

3 7 11 12

6 10 15 16

9 14 23 24

N First Second

315 315

315 630

2 5 6 7

3 7 11 12

6 10 15 16

9 14 23 24

P First Second

500 500

500 1000

3 7 11 12

6 10 15 16

9 14 23 24

Q First Second

800 800

800 1600

0 2 1 2

6 10 15 16

9 14 23 24

R First Second

1250 1250

1250 2500

0 3 3 4

9 14 23 24

S First Second

2000 2000

2000 4000

Double sampling plan for reduced inspection

Sample size code

letter

Sample Sample size

Cumulative sample

size

Acceptable quality level (reduced inspection) 0.065 0.65 1.0 1.5 2.5 4.0


A B C

*

*

*

D First Second

2 2

2 4

*

E First Second

3 3

3 6

* 0 2 0 2

F First Second

5 5

5 10

* 0 2

0 2 0 3 0 4

G First Second

8 8

8 16

0 2 0 2

0 3 0 4

0 4 1 5

H First Second

13 13

13 26

0 2 0 2

0 3 0 4

0 4 1 5

0 4 3 6

J First Second

20 20

20 40

0 2 0 2

0 3 0 4

0 4 1 5

0 4 3 6

1 5 4 7

K First Second

32 32

32 64

0 3 0 4

0 4 1 5

0 4 3 6

1 5 4 7

2 7 6 9

L First Second

50 50

50 100

* 0 4 1 5

0 4 3 6

1 5 4 7

2 7 6 9

3 8 8 12

M First Second

80 80

80 160

0 4 3 6

1 5 4 7

2 7 6 9

3 8 8 12

5 10 12 16

N First Second

125 125

125 250

1 5 4 7

2 7 6 9

3 8 8 12

5 10 12 16

P First Second

200 200

200 400

0 2 0 2

2 7 6 9

3 8 8 12

5 10 12 16

Q First Second

315 315

315 630

0 3 0 4

3 8 8 12

5 10 12 16

R First Second

500 500

500 1000

0 4 1 5

5 10 12 16

=Use first sampling plan below arrow. If sample size equals, or exceeds, lot size, carry out 100% inspection. =Use first sampling plan above arrow. * =Use corresponding single sampling plan (or alternatively use double sampling plan below where available) Ac =Acceptance number. Rc =Rejection number. Note: If after the second sample, Ac has been exceeded, but RC has not been reached, accept the lot, but revert to normal inspection.

NORMAL INSPECTION, LEVEL 1, “S” METHOD

Lot size Level I

ACCEPTABLE QUALITY LEVEL (AQL) 1%

NORMAL TIGHTENED

Sample size

K K

2-8 3 1.45 1.65

9-15 3 1.45 1.65

16-25 3 1.45 1.65

26-50 4 1.45 1.65

51-90 5 1.53 1.65

91-150 7 1.62 1.75

151-280 10 1.72 1.84

281-500 15 1.79 191

501-1200 20 1.82 1.96

1201-3200 25 1.85 1.98

3201-10000 35 1.89 2.03

10001-35000 50 1.93 2.08

35001- 150000 75

1.98

2.12

150001-500000 100 2.00

2.14

>500001 150 2.03

2.18

Annexure-3

HEXAGON SOCKET HEAD CAP SCREWS LF-1151

1. Dimensions: Table No.1

D

Nominal P

Pitch A B C E H

J Max.

K +0.1

M r

3 0.5 2.5 +0.060 +0.020

3 2.2 5.5 1.3 +0.4 +0.0

0.5 0.9 0.8 0.2

to 0.4

4 0.7 3.0 4 2.9 7.0 2.0 1.4 1.0

5 0.8 4.0 +0.105 +0.030

5 3.8 8.5 2.7 0.8

1.6 6 1.0 5.0 6 4.5 10.0 3.3

+0.5 +0.0

2.0 1.2 0.5 to 0.7

8 1.0 6.0 8 6.2 13.0 4.3

1.2 2.4 1.5 10 1.25 8.0

+0.130 +0.040

10 7.9 16.0 5.5 +0.7 +0.0

0.6 to 0.8

12 1.25 10.0 12 9.9 18.0 6.6 +0.9 +0.0

16 1.5 14.0 +0.230 +0.050

16 13.9 24.0 8.8 1.6

3.2 1.8

0.8 1.0

20 1.5 17.0 20 17.9 30.0 10.7 +1.1 +0.0

1.0 1.2

24 2.0 19.0 +0.280 +0.060

24 20.0 36.0 12.9 +1.1 +0.0

2.0 1.0 1.2

2. Threads: ISO Metric thread profile according to NFL 05-220 thread rolling. 3. Tolerance: (a) On threads 4h according to NFL 05-224.

(b) Perpendicularity of the bearing surface of the head w. r. t. the axis: Diameter (D) 3 to 6 8 to 10 12 to 24

⊥ 0.15 0.20 0.25

(c) Perpendicularity of sides with respect to bearing face of head: Diameter (D) 3 to 8 Above 8

⊥ 0.1 (max) 0.2(max)

(d) Flatness of bearing surface: ≤ 50µm

4.Surface roughness: Bearing surface of head, head to shank fillet, thread run out, thread

root, thread sides (before coating): Ra< 0.8 µm

Other surface: 3.2µm

5. Property class: (a) 1100 Mpa Tensile min (Class II) (b) 1250 Mpa Tensile min (Class III) (c) 1550 Mpa Tensile (Class IV)

6. Surface protection: a) Class II & III – Cadmium plating (Electro deposit) and Moly

disulphide dry film lubricant - CEM.

7. Preferred length: Table No.2

8. Identification: Below M8, fastener shall be identified with tag. Above M8, property class and manufacturer shall be indicated on the upper face or the side of the head with the depressed characters of rounded root form and not greater than 0.25 mm depth.

9. Supply condition: Acceptance shall be as per specification

VSSC/SR/QDMF/GEN/183/2006.

Dia M3 M4 M5 M6 M8 M10 M12 M16 M20

Le

ngth

6 6 10 8 8 12 12 16 20 25 30 10 10 16 16 20 25 30 35 40 12 12 20 20 25 30 35 40 45

HEXAGON SOCKET HEAD CAP BOLTS LF-1152

1.Dimension: Table No.1

D Nominal

h12 P

Pitch A B h13 C E H

J Max

K +0.1

M r

3

-0.00 -0.10

0.5 2.5 +0.06 +0.02

3 -0.00 -0.14

2.2 5.5 1.3

+0.0 +0.4

0.3 0.9 0.8

0.2 0.4

4 0.7 3.0 4

-0.00 -0.18

2.9 7 2 1.4 1.0

5 0.8 4.0

+0.105 +0.030

5 3.8 8.5 2.7

0.8

1.2

1.6

6

1.0 5.0 6 4.5 10.0 3.3 +0.0 +0.5

2.0 1.2 0.5 0.7

8 -0.00 -0.15

1.0 6.0 8 -0.00 -0.22

6.2 13 4.3

2.4 1.5 10 1.25 8.0 10 7.9 16 5.5 +0.0 +0.7 0.6

0.8 12

-0.00 -0.18

1.25 10.0 12 -0.00 -0.27

9.9

13.9

18 6.6 +0.0 +0.9

16 1.5 14.0 +0.230 +0.050

16 24 8.8 1.6

3.2 1.8

0.8 1.0

20

-0.00 -0.21

1.5 17.0 20 -0.0 -0.33

17.9 30.0 10.7 +0.0 +1.1

1.0 1.2

24 2.0 19.0 +0.280 +0.060

24 20.0 36.0 12.9 2.0

2. Threads: ISO Metric thread profiles according to NFL 05-220 thread rolling. 3. Tolerance: (a) On threads 4h according to NFL 05-224. (b) Concentricity of head w.r.t. shank:

Diameter (D) 3 to 6 8 to 15 16 to 24 Concentricity 0.15 0.2 0.3

(c) Concentricity of hexagon side w.r.t. bearing face of head:

Diameter (D) 3 to 6 8 to 12 16 to 24 Concentricity 0.15 0.27 0.33

(d) Perpendicularity of bearing surface of head w.r.t. the axis: 0.08

(e) Flatness of the bearing surface ≤ 50 µm 4.Surface Roughness: Bearing surface of head, Shank, head to shank fillet, thread run out,

thread root, thread sides (before coating): Ra< 0.8µm

Other surface: 3.2 µm 5. Property class: (a) 1250 Mpa Tensile min (Class III)

(b) 1550 Mpa Tensile min (Class IV) 6. Surface protection: (a) Class III – Cadmium plating (Electro deposit) and Moly disulphide

dry film lubricant-CEM. (b) Class IV – Cadmium plating (Vacuum deposit) and Moly disulphide dry film lubricant-CVM.

7. Preferred length: Table No.2

Diameter M3 M4 M5 M6 M8 M10 M12 M16 M20 M24

Le

ngth

35 40 45 50 25 30 45 50 60 25 30 30 35 50 60 70 16 16 30 35 35 40 60 70 80 60 20 20 35 40 40 45 70 80 90 70 25 25 40 45 45 50 80 90 100 80 30 30 45 50 50 60 90 100 120 100 35 35 50 60 60 70 100 120 150 120

8. Identification: Below M8, fastener shall be identified with tag. Above M8, property

class and manufacturer shall be indicated on the upper face or the side of the head with the depressed characters of rounded root form and not greater than 0.25 mm depth.

9. Supply condition: Acceptance shall be as per specification VSSC/SR/QDMF/GEN/183/2006.

Length Y, U, L

Table No.3

12 Y U L 24 11 35 24 16 40 24 21 45 24 26 50 24 36 60 24 46 70 24 56 80 24 66 90 24 76 100

10 Y U L 22 8 30 22 13 35 22 18 40 22 23 45 22 28 50 22 38 60 22 48 70

16 Y U L 28 17 45 28 22 50 28 32 60 28 42 70 28 52 80 28 62 90 28 72 100 28 92 120

20 Y U L 32 18 50 32 28 60 32 38 70 32 48 80 32 58 90 32 68 100 32 88 120 32 118 150

6 Y U L 16 9 25 16 14 30 16 19 35 16 24 40 16 29 45 16 34 50 16 44 60

8 Y U L 18 12 30 18 17 35 18 22 40 18 27 45 18 32 50 18 42 60

4 Y U L 12 4 16 12 8 20 12 13 25 12 18 30 12 23 35

5 Y U L 14 11 25 14 16 30 14 21 35 14 26 40 14 31 45 14 36 50

D : 3 Y U L 10 6 16 10 10 20 10 15 25 10 20 30 10 25 35

HEXAGON HEAD BOLTS FR 1150

1.Dimensions: Table No.1

D P Pitch

A B C

E Min

r F Nom h12 h12 h13 J13 J14

3

-0.0 to

–0.1

0.5 5.5 -0.12 -0.0

± 0.9 2.5

±0.125

2.2 6.0 0.2 to 0.4

1

4 0.7 7.0 -0.0 to

–0.15

±0.11

2.5 2.9 7.7 1

5 0.8 8.0 3.0 3.8 8.8 1.2

6 1.0 10

-0.0 -0.22

3.5

±0.15

4.5 11.1 0.5 to 0.7

1.5

8 -0.0 to

–0.15

1.0 13 -0.0 to

-0.27 ±0.135

4.5 6.2 14.5 1.8

10 1.25 17 5.0 7.9 19.0 0.6 to 0.8

1.8

12 -0.0

-0.18

1.25 19

-0.0 -0.33

±0.165

6.0 9.9 21.3 2.0

16 1.5 24 7.5

±0.18

13.9 26.9 0.8 to 1.0

2.0

20 -0.0

-0.21 1.5 30 9.0 17.9 33.7

1.0 to 1.2

2.0

VSSC:FPS:15W:2011 46

2. Threads: ISO Metric thread profile according to NFL 05-220 thread rolling.

3. Tolerance: (a) On threads 4h according to NFL 05-224. (b) Concentricity of head w.r.t. shank:

A 5.5 7 to 10 13 & 17 19 to 30 Concentricity 0.12 0.15 0.18 0.21

(c) Perpendicularity of bearing face w.r.t. axis: 0.3 max (d) Perpendicularity of hexagon side’s w.r.t. bearing surface: Diameter (D) 3 to 8 Above 8

⊥ 0.1 (max) 0.2 (max)

4. Surface Roughness: Bearing surface of head, head to shank fillet, thread run

out, thread root, thread sides (before coating): Ra< 0.8

µm


5. Material: Alloy Steel heat treated (a) 1100 Mpa Tensile min. (Class II) (b) 1250 Mpa Tensile min. (Class III) (c) 1550 Mpa Tensile min. (Class IV)

6. Surface Coating: (a) class-II&III: Cadmium plate (Electro Deposit) and

Moly die sulfide dry film lubricant code: CEM (b) Class-IV: Cadmium plate (Vacuum Deposit) and

Moly disulfide dry film lubricant code: CVM 7. Preferred Length: Table No.2

Diameter M3 M4 M5 M6 M8 X1 M10X1.25

M12 X1.25

M16X1.5

M20X1.5

Le

ngth

35 20 40 45 50 20 25 30 45 50 60

10 25 30 30 35 50 60 70 16 16 30 35 35 40 60 70 80 20 20 35 40 40 45 70 80 90 25 25 40 45 45 50 80 90 100 30 30 45 50 50 60 90 100 120 35 35 50 60 60 70 100 120 150 75


8. Identification: Below M8, fastener shall be identified with tag. Above

M8, property class and manufacturer shall be indicated on the upper face or the side of the head with the depressed characters of rounded root form and not greater than 0.25 mm depth.

9.Supply condition: Acceptance shall be as per specification

VSSC/SR/QDMF/GEN/183/2006. Length U, Y, L Table No.3

D : 3 Y U L 8 2 10 10 6 16 10 10 20 10 15 25 10 20 30 10 25 35

4 Y U L 12 4 16 12 8 20 12 13 25 12 18 30 12 23 35

5 Y U L 14 6 20 14 11 25 14 16 30 14 21 35 14 26 40 14 31 45 14 36 50

6 Y U L 16 4 20

16 9 25 16 14 30 16 19 35 16 24 40 16 29 45 16 34 50 16 44 60

10 Y U L 22 8 30 22 13 35 22 18 40 22 23 45 22 28 50 22 38 60 22 48 70

8 Y U L 19 11 30 19 16 35 19 21 40 19 26 45 19 31 50 19 41 60 19 56 75

12 Y U L 24 11 35 24 16 40 24 21 45 24 26 50 24 36 60 24 46 70 24 56 80 24 66 90 24 76 100

16 Y U L 28 17 45 28 22 50 28 32 60 28 42 70 28 52 80 28 62 90 28 72 100 28 92 120

20 Y U L 33 17 50 33 27 60 33 37 70 33 47 80 33 57 90 33 67 100 33 87 120 33 117 150


HEXAGON HEAD SCREWS 1060

1.Dimensions: Table No.1

D Nomin

al

P Pitch

A h13

A-0.3 h14

B j14

C E r F

3 0.5 5.5

-0.00

-0.18

5.2

-0.00

-0.30

2.5 ±0.125

2.2 6.0 0.2 to 0.4

1.0

4 0.7 7 -0.00

-0.22

6.7 -0.00

-0.36

2.5 2.9 7.7 5 0.8 8 7.7 3.0 3.8 8.8 1.2

6 1.0 10 9.7 3.5

±0.15

4.5 11.1

0.5 to 0.7

1.5

8 1.0 13 -

0.00 -

0.27

12.7 -

0.00 -

0.43

4.5 6.2 14.5

1.8

10 1.25 17 16.7 5.0 7.9 19.0

0.6 to 0.8

1.8

12 1.25 19 -

0.00 -

0.33

18.7 -

0.00 -

0.52

6.0

±0.18

9.9 21.3

2.0

16 1.5 24 23.7 7.5 13.9 26.9

0.8-1.0

2.0

20 1.5 30 29.7 9.0 17.9 33.7

1-1.2 2.0

2. Threads: ISO Metric thread profile according to NFL 05-220

thread rolling.

3. Tolerance: (a) On Threads 4h in accordance with NFL 05-224.


(b) Concentricity of the head w.r.t. the shank (Ref. Drg)

(c) Perpendicularity of the bearing face w.r.t. axis:

(d) Perpendicularity of hexagonal sides w.r.t. bearing face:

(e) Flatness of bearing surface: ≤ 50 µm

4. Surface Roughness: Bearing surface of head, head to shank fillet, thread run out, thread root, thread sides (before coating): Ra <.

0.8µm



6. Surface Coating: (a) class-II&III: Cadmium plate (Electro Deposit) and Moly di sulfide dry film lubricant code: CEM

(b) Class-IV: Cadmium plate (Vacuum Deposit and Moly disulfide dry film lubricant code: CVM

7.Preferred length:

Table No.2

Dia

M3

M4

M5

M6

M8

X1

M10 X1.2

5

M12 X1.2

5

M16

X1.5

M20

X1.5

Length

6 6 10

8 8 12 12 16 20 25 30

10 10 16 16 20 25 30 35 40

12 12 20 20 25 30 35 40 45


M8, property class and manufacturer shall be indicated

A 5.5 7 to 10 13 & 17 19 to 30 Concentricity 0.22 0.15 0.18 0.21

Diameter (D) 3 to 6 8 to 10 12 to 20

⊥ 0.15 0.2 0.25

Diameter (D) 3 to 6 8 to 10 12 to 20

⊥ 0.15 0.20 0.25


on the upper face or the side of the head with the depressed characters of rounded root form and not greater than 0.25 mm depth.



SLOTTED 90°°°° COUNTERSUNK HEAD SCREWS FR-1055


1. Dimension:

Table No. 1

2. Threads: ISO Metric thread profile according to NFL 05-220 thread rolling. 3. Tolerance: (a) On Threads 4h in accordance with NFL 05-224.

(b) Tolerance on 90° CSK is 0° -2°

(c) Perpendicularity of head surface to the axis shall be ±1° (d) Angularity of head bearing surface w.r.t. shank shall be with in 2IT14. (e) Tolerance for length shall be with in js16.

4. Surface Roughness: Bearing surface of head, head to shank fillet, thread run

out, thread root, thread sides (before coating): Ra <.

0.8µm


5. Material: Alloy Steel heat treated

D P A B F G J L

min 3 0.5 6 1.5 0.8 0.8 0.5 5 4 0.7 8 2.0 1.0 1.0 0.6 6 5 0.8 13 2.5 1.2 1.2

0.8 8

6 1.0 12 3.0 1.6 1.5 10 8 1.0 10 4.0 2.0

2.0 1.0 12

10 1.25

20 5.0 2.5 1.2 16


(a) 1100 Mpa Tensile min. (Class II) (b) 1250 Mpa Tensile min. (Class III)

(c) 1550 Mpa Tensile min. (Class IV)

6. Surface coating: (a) class-II&III: Cadmium plate (Electro Deposit) and Moly di sulfide dry film lubricant code: CEM (b) Class-IV: Cadmium plate (Vacuum Deposit) and Moly disulfide dry film lubricant code: CVM

7. Preferred Length:

Table No.2 Dia Length M3 5 6 8 1

0 12

16

M4 6 8 10

12

16

20

25

30

M5 8 10

12

16

20

25

30

35

40

45

50

M6 10

12

16

20

25

30

35

40

45

50

M8 12

16

20

25

30

35

40

45

50

M10

16

20

25

30

35

40

45

50

60

70



9. Supply Condition: Acceptance shall be as per specification


CRUCIFORM 120°°°° COUNTERSUNK HEAD SCREWS FR-1050


Note : Cruciform depth shall conform to NFL 22070 Fillet radius shall conform to NFL 05 200

1. Dimension:

Table No.1 D

Nominal h12

P Pitch

A h12

B h13

-0.0 -0.5 C

E Cruciform nominal

dia

1.6 -0.0 -0.1

0.35 3.2 -0.0 -

0.12

0.54

0.95 0.05 to

0.10

1.6 2 0.4 4.0 0.65 1.25 2 3 0.5 6.0 1.0 2.1 3 4

-0.0 -

0.12

0.7 8.0

-0.0 -

0.15

1.3

-0.0 -

0.14

2.9 0.1 to 0.2

4 5 0.8 10.0 1.6 3.8 5

6 1 12.0 1.9 4.5 0.2 to 0.25

6

8 1 16.0 2.5 6.2 0.25 to 0.35

8

2.Threads: ISO Metric thread profile according to NFL 05-220

thread rolling.

3.Tolerance: (a) On Threads 4h according to NFL 05-224.


(b) Concentricity of the angular face of the axis: 0.2 (max)

(c) Concentricity of cruciform to the axis: 0.2 (max) 4. Surface Roughness: Bearing surface of head, head to shank fillet, thread run

out, thread root, thread sides (before coating): Ra <

0.8µm


5. Material: Alloy Steel heat treated (a) 1100 Mpa Tensile min. (Class II)

(b) 1250 Mpa Tensile min. (Class III) (c) 1550 Mpa Tensile min. (Class IV)

6. Surface Coating: (a) class-II&III: Cadmium plate (Electro Deposit) and Moly die sulfide dry film lubricant code: CEM (b) Class-IV: Cadmium plate (Vacuum Deposit) and Moly disulfide dry film lubricant code: CVM

7. Preferred Length: Table No.2

Size Length 1.6 3 4 5 6 8 10 12 16 2 4 5 6 8 10 12 16 20 3 5 6 8 10 12 16 20 25 4 6 8 10 12 16 20 25 30 5 8 10 12 16 20 25 30 32 35 6 10 12 16 20 25 30 32 35 40 8 12 16 20 25 30 32 35 40 45 50



9.Supply condition: Acceptance shall be as per specification



SLOTTED CHEESE HEAD SCREWS FR-1054



thread rolling.

3. Tolerance: (a) on Threads 4h according to NFL 05-224. (b) Perpendicularity of support face w.r.t shank: 0.08 (max)

4. Surface Roughness: Bearing surface of head, head to shank fillet, thread run out, thread root, thread sides (before coating): Ra< 0.8

µm


Size D

Pitch D1 h14

K h13

n D2 max

T

r min

Min max Min max 3 0.5 5.5 2 0.86 1.0 3.6 0.9 1.15 0.1 4 0.7 7.0 2.6 1.06 1.20 4.7 1.2 1.5 0.2 5 0.8 8.5 3.3 1.26 1.51 5.7 1.5 1.8 0.2 6 1.0 10.0 3.9 1.66 1.91 6.8 1.8 2.2 0.25 8 1.0 13.0 5.0 2.06 2.31 9.2 2.3 2.8 0.4 16 2.0 21.0 8.0 3.3 3.06 18.4 3.6 3.8 0.8


5. Material: Alloy Steel heat treated (a) 1100 Mpa Tensile min. (Class II) (b) 1250 Mpa Tensile min. (Class III)

(c) 1550 Mpa Tensile min. (Class IV) 6. Surface Coating: (a) Class-II&III: Cadmium plate (Electro Deposit) and

Moly di sulfide dry film lubricant code: CEM (b) Class-IV: Cadmium plate (Vacuum Deposit and Moly disulfide dry film lubricant code: CVM

7. Preferred length:

Table No.2 8. Identification: Below M8, fastener shall be identified with tag. Above




Size Length M3 6 8 10 12 16 20 25 30 35 40 M4 6 8 10 12 16 20 25 30 35 40 50 M5 8 10 12 16 20 25 30 35 40 50 M6 10 12 16 20 25 30 35 40 50 M8 12 16 20 25 30 35 40 50 M16 20 25 30 35 40 50


HEXAGON SOCKET COUNTERSUNK HEAD BOLTS FR-1155

1. Dimensions: Table No. 1

Size Pitch D2 h14

b C

Nom e

s D12

k Nom

r Min

t IT 14

M5 0.8 10 16 0.3 3.5 3 2.8 0.2 2.3 M6 1.0 12 18 0.3 4.7 4 3.3 0.3 2.5 M8 1.0 16 22 0.4 5.8 5 4.4 0.5 3.5 M10 1.25 20 26 0.5 7.0 6 5.5 0.5 4.4 M12 1.25 24 30 0.5 9.4 8 6.5 1 4.6

2. Threads: ISO Metric thread profile according to NFL 05-220 thread rolling.

3. Tolerance: (a) On Threads 4h in accordance with NFL 05-224.

(b) Tolerance on CSK 90° shall be 0° -2° (c) Concentricity of head w.r.t. shank shall be with in

2IT13.

(d) Perpendicularity of the head surface w.r.t. axis: ±1° (e) Angularity of head bearing surface w.r.t. shank shall be 2IT13. (f) Parallelism of hexagon socket w.r.t. axis shall be

with in 2IT13.


(g) Tolerance on length shall be with in js16.

4. Surface Roughness: Bearing surface of head, shank, head to shank fillet, thread run out, thread root, thread sides (before

coating): Ra <. 0.8µm



6.Surface Coating: (a) class-II&III: Cadmium plate (Electro Deposit) and

Moly di sulfide dry film lubricant code: CEM (b) Class-IV: Cadmium plate (Vacuum Deposit and

Moly disulfide dry film lubricant code: CVM 7 Preferred Length:

Table No.2 Dia Length

M5 8 10

12

16

20

25

30

35

40

50

M6 10

12

16

20

25

30

35

40

50

M8 12

16

20

25

30

35

40

50

M10

16

20

25

30

35

40

50

60

70

M12

20

25

30

35

40

50

60

70






HEXAGONAL SOCKET 90° COUNTERSUNK HEAD SCREWS FR-1051

1. Dimension:

Table No. 1 Size d1

Pitch d2 h14

X Max

c nom

z max

S D12

K nom

r Min

t IT 14

M4 0.7 8 1.4 0.3 0.7 2.5 2.3 0.2 1.8 M5 0.8 10 1.6 0.3 0.8 3 2.8 0.2 2.3 M6 1.0 12 2.0 0.3 1.00 4 3.3 0.3 2.5 M8 1.0 16 2.0 0.4 1.25 5 4.4 0.5 3.5 M10 1.25 20 2.50 0.5 1.50 6 5.5 0.5 4.4 M12 1.25 24 2.50 0.5 1.75 8 6.5 1 4.6


thread rolling.

3. Tolerance: (a) On threads 4h according to NFL 05-224.

(b) Tolerance on CSK 90° shall be 0° -2° (c) Perpendicularity of head surface w.r.t. the axis:±1°

(d) Parallelism of hexagon socket w.r.t. axis shall be with in 2IT13 (e) Tolerance on length shall be with in js16.


4. Surface Roughness: Bearing surface of head, shank, head to shank fillet, thread run out, thread root, thread sides (before

coating): Ra <. 0.8 µm

Other surface: 3.2 µm


6. Surface Coating: (a) class-II&III: Cadmium plate (Electro Deposit) and

Moly die sulfide dry film lubricant code: CEM (b) Class-IV: Cadmium plate (Vacuum Deposit and

Moly disulfide dry film lubricant code: CVM 7. Preferred Length:

Table No.2 Dia d1

Length

M4 8 10 12 16 20 25 30 35 40 50 M5 8 10 12 16 20 25 30 35 40 50 M6 10 12 16 20 25 30 35 40 50 M8 12 16 20 25 30 35 40 50 M10 16 20 25 30 35 40 50 60 70 M12 20 25 30 35 40 50 60 70






CRUCIFORM 120°°°° COUNTERSUNK HEAD BOLT FR-1156

Note : Cruciform depth shall conform to NFL 22070 Fillet radius shall conform to NFL 05 200


Nominal Dia D

Pitch P

A h12

B h13

C E

3 0.5 6.0 1.0 2.1 0.1-0.2

4 0.7 8.0 1.3 2.9 0.1-0.2

5 0.8 10.0 1.6 3.8 0.1-0.2

6 1 12.0 1.9 4.5 0.2-0.25

8 1 16.0 2.5 6.2 0.25-0.35

Note: X=2 times the diameter (D) including run out.


thread rolling.

3. Tolerance: On threads 4h according to NFL 05-224.


4. Surface Roughness: Bearing surface of head, shank, head to shank fillet, Thread run out, thread root, thread sides (before

coating): Ra< 0.8 µm


5.Material: Alloy Steel heat treated (a) 1100 Mpa Tensile min. (Class II) (b) 1250 Mpa Tensile min. (Class III) (c) 1550 Mpa Tensile min. (Class IV)

6.Surface Coating: (a) class-II&III: Cadmium plate (Electro Deposit) and

Moly di sulfide dry film lubricant code: CEM (b) Class-IV: Cadmium plate (Vacuum Deposit) and

Moly disulfide dry film lubricant code: CVM 7.Preferred Length:

Table No.2 Size

D Length

3 8 10 12 14 16 4 10 12 14 16 18 20 5 10 12 14 16 18 20 22 24 6 14 16 18 20 22 24 8 16 18 20 22 24



