Rubber used in the composition of bearings can be either natural (NR for "Natural Rubber") or synthetic, in which case the compound is generally a chloroprene polymer poly-chloroprene or CR for "Chloroprene Rubber".
The minimum thickness of a sheet, in accordance with EN 1337-3, may in no circumstance be under 5 mm, or over 25 mm.
Technical Features:
Description
A laminated elastomeric bearing is a "block of vulcanized Elastomer (…) reinforced internally by one or several steel plates, chemically glued (bonded) during vulcanization. (…). Elastomer is a macromolecular material that regains its shape and initial dimensions approximately after being submitted to significant deformation under the influence of a low stress variation".
External Forces being supported
Elastomeric bearings permit the simultaneous support of the following loads:
- Standard absorption of vertical loads
- Absorption of briefly applied external horizontal forces
- Horizontal movement in all directions through shear deformation
- Rotation of the bearing surfaces around all axes
Specifications
No | Property | Test Method | Unit | Test Result |
1 | Hardness | ASTM D/2240 | Shore A | |
2 | Tensile Strength |
ASTMD/412 | PSI-min | 1900 |
3 | Elongation at Break |
ASTM D/412 | % | 390 |
4 | Tear Strength |
ASTM D/624 | 1 b/in | 100 |
5 | Abrasion | DIN 53516 | mm3 | 120 |
5 | Compression Set @ 24hr | ASTM /D/395 | % | 25 |
6 | Brittleness | ASTM D/2137 | - | Durable |
7 | Specific Gravity |
- | Gr/cm3 | 1.35 |
8 | Ozone Resistance |
ASTM D/1171 |
After 72hrs @ at 40 deg C Exposure to 50 PPHM in Air |
No cracks |
9 | Heath Resistance |
Up to 100 deg C |
- | Result good to Excellent |
10 | Resistance to Oil based chemicals such as petrol & diesel |
- | - | Result good to Excellent |
Materials Specification
Steel shall conform to ASTM 240 Type 204 with 2B finish.
- Bolts, Nuts , washers and other hardware shall conform to ASTM 240
- Compound: Two types;
- NR Natural Rubber
- CR Chloral Rubber
Quality Control:
Bearings are important elements of structures, such as bridges and viaducts, ensuring that they operate correctly. The durability of the structure depends on their quality, as they are in a constant state of use.The life expectancy of bearings is the result both of their intrinsic qualities and of the care taken of them.
The quality of these products depends on expertise in the manufacturing process. Quality Assurance provisions should enable you the client to:
- Convey the quality required in terms of manufacturing methods
- Obtain the quality required
- Check that it has achieved the quality required
- Justify subsequently that it has been reached and checked.
- AssaFlex products are checked independently at certain intervals such as Esfahan’s Polytechnics or other reputable laboratories.
Quality control procedures will be implemented in the factory such as:
- Tests on samples taken in the factory in accordance with a prescribed test programme.
- Inspection of the ecstatic of the products
For Data sheets 1 CLICK HERE
For Data sheets 2 CLICK HERE
For details to chose Bearing pad sizes click the links below
Bearing Pads Circ-150-300mm | Bearing Pads Circu-350-500mm |
Bearing Pads Circ-600-800mm | Bearing Pads Circ-850-900mm |
Bearing Pads Rec-100-200mm | Bearing Pads-Rec 200-350mm |
Bearing Pads Rec 400-500mm | Bearing Pads Rec 600-800mm |