Extruded Rubber Tolerances

The use of extruded seals is extremely diverse. You will find extrusions in many types of manufacturing processes for a variety of purposes. Applications include but are not limited to: door and window seals in the architectural environment and automotive, appliance and aircraft industries; bearing seals; bumpers; heater gaskets; radiator overflow tubing; vacuum cleaner belts; ladder foot grips, and cushions on bars or handles. The applications are endless and expanding rapidly with innovative engineering of extrudable materials.

Materials which can be extruded include dense and sponge rubber from a variety of compounds to meet your specific environment and application. These compounds include Nitrile, EPDM, Natural rubber, Neoprene, Viton®, Urethane, Silicone and many others. Whether your application requires a long or short run, Monroe Seals will service your needs with the appropriate compound. Extrusions can be diversified for use by many secondary operations such as cut lengths, vulcanized to be endless, and formed and notched to allow a variety of shapes and sizes of products.

Most extrusions are custom profiles which are tooled to meet your blueprint requirements. This is an extremely competitive method of manufacturing due to reasonable tooling costs. There are also standard cord (rod), tubing and channels available.

The tolerance tables in the following pages have been developed by the Rubber Manufacturers Association to assist in your design work.

TABLE 12. SUMMARY OF RMA DRAWING DESIGNATIONS EXTRUDED RUBBER PRODUCTS

RMA Class Dimensional Tolerance* Table 13 CutLength Tolerance* Table 16 SplicedLength Tolerance* Table 16 MandrelCured* Table 20
1 E1 L1 S1 EN1
2 E2 L2 S2 EN2
3 E3 L3 S3 EN3
4 - - - -

 

TABLE 13 - STANDARD CROSS-SECTIONAL TOLERANCE

RMA Class 1
High Precision
2
Precision
3
Commercial
Drawing Designation E1 E2 E3
 Dimensions (mm)        
Above Up To  
0 1.5 +/- 0.15 +/- 0.25 +/- 0.40
1.5 2.5 0.20 0.35 0.50
2.5 4.0 0.25 0.40 0.70
4.0 6.3 0.35 0.50 0.80
6.3 10 0.40 0.70 1.00
10 16 0.50 0.80 1.30
16 25 0.70 1.00 1.60
25 40 0.80 1.30 2.00
40 63 1.00 1.60 2.50
63 100 1.30 2.00 3.20

 

RMA Class 1
High Precision
2
Precision
3
Commercial
Drawing Designation E1 E2 E3
 Dimensions (in)        
Above Up to      
0 0.06 +/- 0.006 +/- 0.010 +/- 0.015
0.06 0.10 0.008 0.014 0.020
0.10 0.16 0.010 0.016 0.027
0.16 0.25 0.014 0.020 0.031
0.25 0.39 0.016 0.027 0.039
0.39 0.63 0.020 0.031 0.051
0.63 0.98 0.027 0.039 0.063
0.98 1.57 0.031 0.051 0.079
1.57 2.48 0.039 0.063 0.098
2.48 3.94 0.051 0.079 0.126

 

TABLE 16 - CUT LENGTH TOLERANCE FOR UN-SPLICED EXTRUSION

RMA Class 1
Precision
2
Commercial
3
Non-Critical
Drawing Designation L1 L2 L3
 Length (mm)        
Above Up to      
0 40 +/- 0.7 +/- 1.0 +/- 1.6
40 63 0.8 1.3 2.0
63 100 1.0 1.6 2.5
100 160 1.3 2.0 3.2
160 250 1.6 2.5 4.0
250 400 2.0 3.2 5.0
400 630 2.5 4.0 6.3
630 1000 3.2 5.0 10.0
1000 1600 4.0 6.3 12.5
1600 2500 5.0 10.0 16.0
2500 4000 6.3 12.5 20.0
4000   0.16% 0.32% 0.50%

 

 Drawing Designation      
 Length (in)      
Above Up to      
0 1.6 +/- 0.03 +/- 0.04 +/- 0.06
1.6 2.5 0.03 0.05 0.08
2.5 4.0 0.04 0.06 0.10
4.0 6.3 0.05 0.08 0.13
6.3 10.0 0.06 0.10 0.16
10.0 16.0 0.08 0.13 0.20
16.0 25.0 0.10 0.16 0.25
25.0 40.0 0.13 0.20 0.40
40.0 63.0 0.16 0.25 0.50
63.0 100.0 0.20 0.40 0.63
100.0 160.0 0.25 0.50 0.80
160.0   0.16% 0.32% 0.50%

 

TABLE 18 - SPLICED LENGTH TOLERANCES

RMA Class   1
(Precision)
2
(Commercial)
3
(Non-Critical)
Drawing Designations   S1 S2 S3
Millimeters
Above Up To
Inches  
Above Up To      
0 -10 + 0.13 + 0.25 + 0.28
10 -16 0.16 0.28 0.32
16 -25 0.20 0.32 0.36
25 -40 0.25 0.36 0.40
40 -63 0.32 0.40 0.45
63 -100 0.40 0.45 0.50
100 - Over 0.50 0.50 0.53

 

TABLE 20 - TOLERANCES ON INTERNAL DIMENSIONS OF MANDREL-SUPPORTED EXTRUSIONS

RMA Class   1
(Precision)
2
(Commercial)
3
(Non-Critical)
Drawing Designations   EN1 EN2 EN3
Nominal Dimensions(in Millimeters)        
Above Up To      
0 4 + 0.20 + 0.20 + 0.35
4 6.3 0.20 0.25 0.40
6.3 10 0.25 0.35 0.50
10 16 0.35 0.40 0.70
16 25 0.40 0.50 0.80
25 40 0.50 0.70 1.00
40 63 0.70 0.80 1.30
63 100 0.80 1.00 1.60
100 160 1.00 1.30 2.00
160   0.6% 0.8% 1.2%
Nominal Dimensions(in Inches)        
Above Up To      
0 0.16 + 0.008 + 0.008 + 0.014
0.16 0.25 0.008 0.010 0.016
0.25 0.40 0.010 1.014 0.020
0.40 0.63 0.014 0.016 0.028
0.63 1.00 0.016 0.020 0.032
1.00 1.60 0.020 0.028 0.040
1.60 2.50 0.028 0.032 0.051
2.50 4.00 0.032 0.040 0.063
4.00 6.30 0.040 0.051 0.079
6.30   0.6% 0.8% 1.2%

Are you looking for seals, rubber, o-rings & gaskets?

Submit an RFQ now!