Automotive Case Studies

Vesconite Hilube bushings were used as suspension bushings in a modified 4×4 vehicle at the Dakar Rally. The polymer bushings were thoroughly tested prior to the rally. The gruelling 9,000km Dakar Rally is a multi-country South American endurance race through various terrains, including sand dunes, mountains and salt flats. Suspension bushings are considered important in vehicle safety, ride comfort and handling and also align suspension and steering components, paramount in the Dakar, in which vehicles travel at between 100 kph and 200 kph in all kinds of terrain over 15 days. In the Dakar 4×4 vehicle, the bushings were exposed to an oscillating movement with many cycles per minute taking place, and performed much better than the nylon-molybdenum bushings that they replaced.

To compare the performance of Vesconite and OEM bronze bushings, hanger and spring eye bushings in Vesconite and bronze were fitted to an RE 29 Leyland petrol tanker used in the Northern Cape, South Africa. Vesconite was fitted to the off road side, the side where bushing wear is generally highest. The bronze bushings were fitted to the road side.

Regular greasing of the hanger and spring eye bushings through the nipples should be carried out. But in practice lubrication is often neglected.

A high proportion of the roads used by the tanker in this trial were dirt roads. This means that the bushings were subjected to excessive dirt and dust. The tanker was in almost constant use, making the trial a severe one.

After two years the bushings on the tanker were inspected. The bronze bushings were completely worn out. As may be seen in the photograph some had worn through to the housing.

Severe pin wear and even housing damage occurred. All the pins had to be replaced.

The Vesconite bushings were still working well with less than 0,2mm (0.008″) wear measured.

Negligible pin wear was found on the Vesconite side and the pins could be reused.

Bronze could not survive the dirt, dust and infrequent greasing. The ability of Vesconite to withstand the effects of dust, dirt and a lack of grease is illustrated particularly well in this application.

A South African enthusiast imported a Raceco off-road racing car from the United States where it is manufactured and assembled.

Within four races, the four front radius suspension arm bushings had worn badly and damaged the mating shafts. The steering was adversely affected. The bushings had to be replaced and the shafts re-finished.

The acetal bushings were replaced with Vesconite bushings. The bushings successfully operated for a full season of six races without further attention other than lubrication.

Vesconite is also used on the back suspension, again successfully replacing the original imported bushings.

The advantages of using Vesconite in these applications are:

• Availability – produced in a wide size range of bushings for easy machining and replacement
• Competitive cost
• Longer life
• No shaft damage
• Minimum maintenance

South Africa – Vesconite flanged pivot bushings have been successfully installed and used on container trailers at the national rail utility. The Vesconite bushes, with a flange of 205 mm diameter and a bore of 165 mm, were fitted to the walking beam centre pivot bearing that equalises component parts of the rear axle bogies. This heavy duty application required a material which had high load carrying capacity, low friction, high wear resistance and good dimensional stability. Vesconite, with all these characteristics, was used on the trailers that are used to transport 12-m-long general purpose containers.

South Africa – Mechanical and aeronautical engineering students at the University of Pretoria, in South Africa, are using Vesconite bushings in their tyre test rig, located at the University’s Vehicle Dynamics Group. The rig consists of a shaft that is pushed axially through the bushes by an actuator. On the other end of the rig is a metal plate that is pushed against a tyre when it is tested. The rig currently tests small commercial vehicle tyres, but the intention is for the Vehicle Dynamics Group to test larger dump truck tyres.

Asia-Pacific / Australia-New Zealand – Vesconite and Vesconite Hilube bushings continue to be ordered by a large manufacturer and supplier of trailer axles in Australasia. The company converted to Vesconite and Vesconite Hilube bushings over a decade ago, having used nylon previously, and continues to order hundreds of bushings, advertising that it has partnered with global experts in truck and trailer technology to ensure savings in maintenance and downtime. The Vesconite and Vesconite Hilube bushings are wear resistant, operate quietly and do not delaminate or distort under high loads. The self-lubricating bushings outlive bronze or nylon and, for axle manufacturers, the bushings also offer the opportunity of extending the warrantee offered with axles.

Argentina – Vesconite Hilube bushings were used as suspension bushings in a modified 4×4 vehicle at the Dakar Rally. The polymer bushings were thoroughly tested prior to the rally. The gruelling 9,000km Dakar Rally is a multi-country South American endurance race through various terrains, including sand dunes, mountains and salt flats. Suspension bushings are considered important in vehicle safety, ride comfort and handling and also align suspension and steering components, paramount in the Dakar, in which vehicles travel at between 100 kph and 200 kph in all kinds of terrain over 15 days. In the Dakar 4×4 vehicle, the bushings were exposed to an oscillating movement with many cycles per minute taking place, and performed much better than the nylon-molybdenum bushings that they replaced.