A manufacturer of heavy commercial vehicles has introduced Vesconite Bearings’ Vescoflex, a tough advanced elastomer, into vibration dampers used on its trucks and buses.
The move follows years of development between the vehicle manufacturer and Vesconite Bearings to create a more durable and cost-effective alternative to the rubber previously used in the vibration damper. The new damper is designed to withstand the demanding conditions encountered in heavy automotive applications while preventing the tearing and collapse that had affected the previous rubber component.
The manufacturer now supplies the Vescoflex-based damper as an OEM replacement part for some of its models. Vesconite Bearings produces the complete damper at its facilities and is supplying dampers to national branches of the vehicle manufacturer.
The damper consists of a unique washer design and bolts, with Vescoflex injection moulded around the components. The moulding process integrates the washers and bolts into the elastomer, helping to prevent the assembly from pulling apart under the repeated movement and vibration experienced in service.
This construction is an important part of the solution. The performance of the damper comes from both the properties of Vescoflex and the way the material is moulded around the mechanical components.
The material, Vescoflex, meanwhile provides a combination of elasticity, strength and resistance to mechanical damage that is suited to the application. It has an elongation at break of 800%, tensile strength of 41 MPa and compression modulus of 51 MPa. The material also has a reported 62% Bashore resilience and tear-strength (Split Die C) results of up to 12 MPa.
The material’s resistance to abrasion and oil adds to its suitability for demanding vehicle applications. Vesconite Bearings reports 100 mg/1,000 cycles in the specified Taber abrasion test and no change in modulus after seven days in ASTM Oil No. 3 at 100°C.
These properties are relevant to the failure modes experienced with the previous rubber damper. Vescoflex’s high tensile strength, tear resistance and oil and grease resistance help it withstand deformation, while its compression properties help it maintain its form under load.
For Vesconite Bearings, the application demonstrates how an engineered elastomer can be combined with component design to address a specific durability challenge in heavy commercial vehicles.
The long development period also illustrates the importance of working closely with an OEM when adapting an elastomeric component for demanding automotive service. Rather than simply changing the material, the two companies refined the complete damper to provide a simpler, more cost-effective component designed around the requirements of the vehicle.
