Non-original spare parts may differ greatly from the parts installed on the device. Many manufacturers offer silent blocks or in other words polyurethane bushings, promising serious advantages over rubber ones. Let’s find out how true their statements are.
It is correct to call this part a rubber-metal hinge. It absorbs shock loads and vibrations due to the elasticity of the material used. This increases the service life of the vehicle and increases the level of comfort. The advantage of a polyurethane bushing over a traditional metal hinge is its simplicity, low price and maintenance-free design. The disadvantage is a shorter service life.
Their usage
Polyurethane bushings are used at the joints of suspension parts. They absorb the loads that occur during the operating stroke of levers, shock absorbers and stabilizers.
When replaced in a timely manner, rubber-to-metal joints improve vehicle handling, reduce steering wheel vibrations when driving over uneven surfaces, and also dampen noise and vibration. Failures manifest themselves in the rumble, squeaks and other unpleasant symptoms of wear on the chassis of the car.
Materials used
Most silent blocks are made from natural rubber. They do an excellent job of absorbing loads, but wear out quickly and often require replacement. Having noticed this problem, many manufacturers have decided to add polyurethane to the suspension.
Polyurethane is a durable synthetic material that is used in the production of soles for hiking shoes, protective films for car bodies, and even sound insulation for aircraft. In its pure form it is very hard, which has a bad effect on the driving performance of the car. Therefore, for the production of silent blocks, a composite consisting of a mixture of polyurethane and rubber is usually used.
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