Fasteners

  • fasteners
  • fasteners2
  • Bolts-Nuts
  • Screws

BOLTS:

STUD BOLTS, HEX HEAD BOLTS, SOCKET HEXAGON HEAD SCREW ANCHOR BOLTS, U-BOLTS, J BOLTS, MUSHROOM HEAD SQUARE NECK BOLTS , T- HEAD BOLTS , WING SCREW , EYE BOLT , EYE BOLT, FOUNDATION BOLTS, STRUCTURAL BOLTS.

WASHER:

PLAIN WASHER , PLAIN BIG & SMALL OD WASHER , SPRING LOCK WASHER , SPRING WASHER HEAVY DUTY , TOOTH WASHER , STAR WASHER , TAB WASHER WITH ONE & TWO TAB

NUTS:

HEXAGON NUTS , HEXAGON COUPLING NUTS , HEXAGON THIN NUT , SQUARE NUT , HEXAGON CASTLE NUTS , SELF LOCKING NUT , HEXAGON DOMED CAP NUTS.

SCREW:

PAN HEAD SLOTTED SCREWS , CHEESE HEAD SLOTTED SCREWS , COUNTERSUNK HEAD SLOTTED SCREWS , COUNTERSUNK RAISED HEAD SLOTTED SCREWS , PAN PHILLIPSE HEAD SCREW , COUNTERSUNK PHILLIPSE RAISED HEAD SCREWS , SLOTTED CHEESE TRIM HEAD MACHINE SCREWS , SOCKET HEAD ALLEN CAP SCREWS , ALLEN COUNTERSUNK SOCKET HEAD CAP SCREWS , SOCKET HEAD SHOULDER SCREWS , SOCKET HEAD CAP SCREW LOW HEAD , HEXAGON SOCKET SET SCREW WITH FLAT POINT , HEXAGON SOCKET SET SCEWS WITH CONE POINT , HEXAGON SOCKET SET SCREW WITH DOG POINT , HEXAGON SOCKET SET SCREWS WITH DOG POINT , HEXAGON SOCKET SET SCREWS WITH CUP POINT , IMPRIAL SOCKET CAP SCREWS .

Fasteners

A Fastener is a hardware device that mechanically joins or affixes 2 or more objects together. In general fasteners are used to create non-permanent joints. These joints can be removed or dismantled as and when required and without damaging the joining components.

Fasteners are usually made from Stainless Steel, Carbon Steel and Alloy Steel.

Fasteners are fitting and tightening products such as Screw, Bolt, Nuts and Washer.

Just like all other products made from Stainless, Copper and Alloy Steel. Fasteners also have their standards and chemical compositions and they are mentioned below.

Chemical composition for Fasteners

CLASS MATERIAL AND TREATMENT C C P S B TEMPERING TEMP. [C]
MIN MAX MAX MAX MAX
4.6 CARBON STEEL QUENCHED AND TEMPERED – 0,20 0,05 0,06 0,003 –
4.8 CARBON STEEL QUENCHED AND TEMPERED – 0,55 0,05 0,06 0,003 –
5.6 CARBON STEEL QUENCHED AND TEMPERED 0,13 0,55 0,05 0,06 0,003 –
5.8 CARBON STEEL QUENCHED AND TEMPERED 0,13 0,55 0,05 0,06 0,003 –
6.8 CARBON STEEL QUENCHED AND TEMPERED – 0,55 0,05 0,06 0,003 –
8.8 CARBON STEEL WITH ADDITIVES (E.G. B, MN OR CR) QUENCHED AND TEMPERED 0.15 (D) 0.4 0.025 0.025 0.003 425
CARBON STEEL QUENCHED AND TEMPERED 0.25 0.55 0.035 0.025
10.9 CARBON STEEL WITH ADDITIVES (E.G. B, MN OR CR) QUENCHED AND TEMPERED 0.15 (D) 0.35 0.025 0.025 0.003 340
CARBON STEEL QUENCHED AND TEMPERED 0.25 0.55 0.025 0.025 0.003 425
CARBON STEEL WITH ADDITIVES (E.G. B, MN OR CR) QUENCHED AND TEMPERED 0.20 (D) 0.55 0.025 0.025
ALLOY STEEL QUENCHED AND TEMPERED (G) 0.2 0.55 0.025 0.025
12.9 ALLOY STEEL QUENCHED AND TEMPERED (G) 0.28 0.5 0.025 0.025 0.003 380

 

(D) IN CASE OF PLAIN CARBON BORON STEEL WITH A CARBON CONTENT BELOW 0.25% (LADLE ANALYSIS), MIN MANGANESE 0.6% FOR 8.8 AND 0.7% FOR 10.9

(G) ALLOY STEEL SHALL CONTAIN ONE OF THE FOLLOWING ELEMENTS: CHROMIUM 0.30%, NICKEL 0.30%, MOLYBDENUM 0.20%, VANADIUM 0.10%

Mechanical properties of screws and studs

No. Mechanical properties property classes
4,6 4,8 5,6 5,8 6,8 8.8 8,8 9,8 10,9 12,9
d<16 mmᵃ d>16 mmᵇ d<16 mm
1 Tensile strength, Rm, MPa nom. ° 400 500 600 800 900 1000 1200
min. 400 420 500 520 600 800 830 900 1040 1220
2 Lower proof stress ReL ᵈ, MPa nom. ᶜ 240 – 300 – – – – – – –
min. 240 – 300 – – – – – – –
3 Yield strength, Rp0.2, MPa nom. ᶜ – – – – – 640 640 720 900 1080
min. – – – – – 640 660 720 940 1100
4 Yield strength at 0.0048 d for whole screw, Rpf, MPa nom. ᶜ – 320 – 400 480 – – – – –
min. – 340ᵉ – 420ᵉ 480ᵉ – – – – –
5 Proof stress, Spᶠ, MPa nom. 225 310 280 380 440 580 600 650 830 970
Stress during proofing load testing ᴼ 0,94 0,91 0,93 0,90 0,92 0,91 0,91 0,90 0,88 0,88
6 Elongation after fracture (test specimen), A, % min. 22 – 20 – – 12 12 10 9 8
7 Contraction after fracture (test specimen), Z, % min. – 52 48 48 44
8 Elongation after fracture, Af (whole screw) min. – 0,24 – 0,22 0,20 – – – – –
9 Ductility in event of head soundness test Inget brott
10 Vickers hardness, HV min. 120 130 155 160 190 250 255 290 320 385
F ≥ 98 N max. 220ᵍ 250 320 335 360 380 435
11 Brinell hardness, HBW min. 114 124 147 152 181 238 242 276 304 366
F = 30 D² max. 209ᵍ 238 304 318 342 361 414
12 Rockwell hardness, HRB min. 67 71 79 82 89 –
max. 95,0ᵍ 99,5 –
Rockwell hardness, HRC min. – 22 23 28 32 39
max. – 32 34 37 39 44
13 Surface hardness, HV 0.3 max. – h h, i h, j
14 Min. height of non-decarburised zone, min. – ½ H1 ⅔ H1 ¾ H1
E, mm
Max. depth of complete decarburisation, max. – 0,015
G, mm
15 Reduction in hardness after re-annealing, HV max. – 20
16 Fracture torque, MB,Nm min. – regarding to ISO 898-7
17 Impact strength, Kᵥᵏ˴ˡ, J min. – 27 – 27 27 27 27 m
18 Surface defects ISO 6157-1ⁿ ISO
6157-3