GN 6339

Washers for heavy duty applications

SKU: 8285 Category:
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Technical Drawing

Product Details

Standard Elements Main dimensions for threaded bolts Weight
Description d1 H13 D h13 d2 H13 l1 ±0.2 L ±0.2
GN 6339-6.3-12-2.5-BT 6.3 12 7 0.6 2.5 M6
GN 6339-6.3-17-3-BT 6.3 17 7 1 3 M6
GN 6339-8.4-16-2.5-BT 8.4 16 9.5 0.75 2.5 M8
GN 6339-8.4-21-4-BT 8.4 21 9.5 1.5 4 M8
GN 6339-10.4-20-3-BT 10.4 20 11.5 0.75 3 M10
GN 6339-10.4-25-4-BT 10.4 25 11.5 1.5 4 M10
GN 6339-12.5-24-3.5-BT 12.5 24 14 1 3.5 M12
GN 6339-12.5-30-6-BT 12.5 30 14 2 6 M12
GN 6339-14.5-28-3.5-BT 14.5 28 16 1 3.5 M14
GN 6339-14.5-36-6-BT 14.5 36 16 2 6 M14
GN 6339-16.5-30-4-BT 16.5 30 18 1 4 M16
GN 6339-16.5-40-6-BT 16.5 40 18 2 6 M16
GN 6339-18.5-34-5-BT 18.5 34 21 1.5 5 M18
GN 6339-18.5-44-8-BT 18.5 44 21 2.5 8 M18
GN 6339-20.5-37-5-BT 20.5 37 23 1.5 5 M20
GN 6339-20.5-44-8-BT 20.5 44 23 2.5 8 M20
GN 6339-22.5-40-5-BT 22.5 40 25 1.5 5 M22
GN 6339-22.5-50-8-BT 22.5 50 25 2.5 8 M22
GN 6339-24.5-44-5-BT 24.5 44 27 1.5 5 M24
GN 6339-24.5-50-10-BT 24.5 50 27 3.5 10 M24
GN 6339-28-50-6-BT 28 50 31 1.5 6 M27
GN 6339-28-60-10-BT 28 60 31 3.5 10 M27
GN 6339-31-56-6-BT 31 56 34 1.5 6 M30
GN 6339-31-68-10-BT 31 68 34 3.5 10 M30
GN 6339-37-66-7-BT 37 66 40 2 7 M36
GN 6339-6.3-12-2.5-GO 6.3 12 7 0.6 2.5 M6
GN 6339-6.3-17-3-GO 6.3 17 7 1 3 M6
GN 6339-8.4-16-2.5-GO 8.4 16 9.5 0.75 2.5 M8
GN 6339-8.4-21-4-GO 8.4 21 9.5 1.5 4 M8
GN 6339-10.4-20-3-GO 10.4 20 11.5 0.75 3 M10
GN 6339-10.4-25-4-GO 10.4 25 11.5 1.5 4 M10
GN 6339-12.5-24-3.5-GO 12.5 24 14 1 3.5 M12
GN 6339-12.5-30-6-GO 12.5 30 14 2 6 M12
GN 6339-14.5-28-3.5-GO 14.5 28 16 1 3.5 M14
GN 6339-14.5-36-6-GO 14.5 36 16 2 6 M14
GN 6339-16.5-30-4-GO 16.5 30 18 1 4 M16
GN 6339-16.5-40-6-GO 16.5 40 18 2 6 M16
GN 6339-18.5-34-5-GO 18.5 34 21 1.5 5 M18
GN 6339-18.5-44-8-GO 18.5 44 21 2.5 8 M18
GN 6339-20.5-37-5-GO 20.5 37 23 1.5 5 M20
GN 6339-20.5-44-8-GO 20.5 44 23 2.5 8 M20
GN 6339-22.5-40-5-GO 22.5 40 25 1.5 5 M22
GN 6339-22.5-50-8-GO 22.5 50 25 2.5 8 M22
GN 6339-24.5-44-5-GO 24.5 44 27 1.5 5 M24
GN 6339-24.5-50-10-GO 24.5 50 27 3.5 10 M24
GN 6339-28-50-6-GO 28 50 31 1.5 6 M27
GN 6339-28-60-10-GO 28 60 31 3.5 10 M27
GN 6339-31-56-6-GO 31 56 34 1.5 6 M30
GN 6339-31-68-10-GO 31 68 34 3.5 10 M30
GN 6339-37-66-7-GO 37 66 40 2 7 M36

Additional information

Chamfer angle α = 70° ± 2°

This relatively large angle is necessary when using hexagon headed bolts, which usually have a tapered transfer from shank to head (the so-called trumpet) to avoid fouling of the washer.

Chamfer edge F

The extended chamfer side F as seen from d<SUB>2</SUB> creates with d<SUB>1 </SUB>an edge the so-called trumpet of the transfer from shank to head of the bolt, so that the smallest radial clearance prevails. Even with the smallest angle of 68° and the lower dimension of d<SUB>2 </SUB>and d<SUB>1 </SUB>the radial clearance of all bolts to DIN EN is still sufficient.

Chamfer face diameter d2

This dimension is, together with the chamfer angle α 70° and the inside diameter d<SUB>1</SUB>, the most important dimension of these heavy duty washers. Diameter d<SUB>2</SUB> is actually, even in the lower tolerance range, larger than the max. contact under head diameter on a bolt. This will ensure that the chamfer of d<SUB>2</SUB> of the hardened washer will not be pressed into the underhead radius causing an indentation on the bolt which would damage the bolt.

Features and applications

The influence of a washer on the quality of the screwed connection is very often understimated. With washers GN 6339, high quality preloaded screwed connections can be established. A high static clamping force can be reached avoiding loss of tension.<BR>At a specified preloaded clamping force it is often possible to use thinner bolts. This can result in a better ratio between clamping distance and bolt diameter to minimise the danger of failure.<BR>The case hardened smooth bolt head/screw contact face leads to a lower and more constant friction coefficient even when continuous clamping and releasing operations are required.<BR>Washers GN 6339 are only suitable for machine construction bolts of classes 8.8 / 10.9 / 12.9, and not for steel bolts DIN 6914.

Inside diameter d1

The inside diameter d<SUB>1 </SUB>is kept as small as possible ensuring that the bolt is inserted centrically into the washer. The choice of a matching pair of bolt and washer with least radial clearance is important in order to avoid a mismatch between chamfer diameter d<SUB>2 </SUB>and the max. contact area diameter of the bolt head.

Lead height h2

This is the height of the cylindrical part of the internal diameter d<SUB>1</SUB>, h<SUB>2</SUB> should be as high as possible in relation to the pitch of the thread of the bolt.

Material

– Version <STRONG>BT</STRONG>: case hardened black oxide steel, material-no. 1.7227, fine machined and fine ground, tensile strength Rm = 1220 – 1400 N/mm<SUP>2</SUP>.<BR>- Version <STRONG>GO</STRONG>: case hardened steel treated GEOMET 500, material-no. 1.7227, fine machined and fine ground, tensile strength Rm = 1220 – 1400 N/mm<SUP>2</SUP>.

Outside diameter D

The outside diameter D of the lower refers to washers DIN 125 / ISO 7089, and the higher type to washers DIN 7349.

Washer thickness L

Washers GN 6339 are higher when compared with DIN washers (exception: DIN 7439 which is equal to the high type). A larger thickness leads to a stronger washer. As a result, bearing in mind the chamfer d<SUB>2</SUB>, a minimum height is established which ensures that the bolt thread will not be damaged when the bolt is tightened.

Additional Technical Drawing