# What tolerances does an extension spring have?

The different series follow different standards.

The properties of the wire material and production methods mean that dimensions and the physical constants can vary from production to production, which are all parameters that have an impact on the function of the extension spring.

A range:
The A Range consists of springs with 5 digits, ie: "31200"

All dimensions and forces in accordance with DIN 2097 (Grade 2). DIN 2097 defines the force as the determining parameter. The number of coils may therefore vary and is consequently not stated for these ranges.

Mean diameter (Dm) tolerances

Dm (mm)
From
To
0,63
1,00
1,00
1,60
1,60
2,50
2,50
4,00
4,00
6,30
6,30
10,00
10,00
16,00
16,00
25,00
25,00
31,50
31,50
40,00
40,00
50,00
50,00
63,00
63,00
80,00
80,00
100,00
100,00
125,00
125,00
160,00
160,00
200,00
Vikleforhold (Dm / d)
4 ⇒ 8
8 ⇒ 14
14 ⇒ 20
+ - 0,07
+ - 0,10
+ - 0,15
+ - 0,08
+ - 0,10
+ - 0,15
+ - 0,10
+ - 0,15
+ - 0,20
+ - 0,15
+ - 0,20
+ - 0,25
+ - 0,20
+ - 0,25
+ - 0,30
+ - 0,25
+ - 0,30
+ - 0,35
+ - 0,30
+ - 0,35
+ - 0,40
+ - 0,35
+ - 0,45
+ - 0,50
+ - 0,40
+ - 0,50
+ - 0,60
+ - 0,50
+ - 0,60
+ - 0,70
+ - 0,60
+ - 0,80
+ - 0,90
+ - 0,80
+ - 1,00
+ - 1,10
+ - 1,00
+ - 1,20
+ - 1,40
+ - 1,20
+ - 1,50
+ - 1,70
+ - 1,40
+ - 1,90
+ - 2,20
+ - 1,80
+ - 2,30
+ - 2,70
+ - 2,10
+ - 2,90
+ - 3,30

Total length (L0) tolerances

L0 (mm)
From
To
0,00
10,00
10,00
16,00
16,00
25,00
25,00
40,00
40,00
63,00
63,00
100,00
100,00
160,00
160,00
250,00
250,00
400,00
400,00
Coil ratio (Dm / d)
4 -> 8
8 -> 20
0,40
0,50
0,50
0,60
0,60
0,70
0,80
0,90
1,10
1,30
1,50
1,80
2,00
2,40
2,50
3,00
3,00
4,00
1,5% of L0
1,5% of L0

Range B: The B Range consists of springs with 11 digits, ie: E03600552000M

The tolerance of the external diameter and length is defined based on the tables below:

Mean diameter (Dm) tolerances

De (mm)
From
To
Tolerance
1,45
3,02
+ - 0,08
3,05
6,10
+ - 0,13
6,12
12,70
+ - 0,20
12,73
25,40
+ - 0,38
24,43
31,12
+ - 0,51
31,14
37,08
+ - 0,76
37,11
50,08
+ - 1,02

Total length (L0) tolerances

L0 length (mm)
From
To
Tolerance
3,05
25,40
+ - 0,79
25,41
38,10
+ - 1,58
38,11
88,90
+ - 3,18
88,91
152,40
+ - 4,78