trailing arm

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Post on 09-Jan-2016

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For calculationTrailing armTrailing arm has its own advantage which makes it different from other suspension arms. When it goes into droop wheel base decreases and when in bump wheel base increases. This is because the wheel moves in circular arc about the pivot axis when seen in side view. Semi trailing arm is parallel or with some angle to the cars longitudinal axis. It is of two type Trailing arm Semi trailing armTrailing arm When arm is parallel to the longitudinal axis of vehicle.Semi Trailing arm When arm is making some angle with longitudinal axis.These are used as rear suspension of vehicle. It is basically an arm which has one end that swivels on the sub frame attached to a spring, kind of like what you get on a motorbikes rear wheel. Its arm is quite bigger than other type of suspension arms. It is very much rigid at the wheel point which stops its false movement. There is no chance of camber gain or loss. It has low unsprung mass and made up of aluminium. When it is compared with double wishbone then, adjustments are definitely possible with either suspension type, only difference it makes is that it is much easier to adjust A-arms over trailing arms. Trailing arms get tricky if you want to be able to adjust camber, castor and toe.Pure trailing arm suspensions have a roll centre at ground level and instant centres at infinity resulting in as mentioned before no camber change and also a large amount of tire scrub. A semi-trailing arm suspension allows you to place the roll centre wherever you desire as well as placing the instant centre in a desirable place. This will allow you to have camber change and somewhat tune the camber curve based on analysis. Both the camber change and tire scrub will stay constant. The roll centre can also be placed in a position which allows for reaching a roll gradient that you desire. The semi-trailing arm maybe a little more complicate then a pure trailing arm but it is simpler than a double wishbone. Both pure trailing arm and semi-trailing arm suspensions put large loads of the connections between the chassis and the arm and if the bushing or bearing can deform, the result will be oversteer.For bushing Baja vehicles have always used Delrin Nylon for all the suspension bushings due to its durability and ease of machining. In the past it has been proven that Delran Nylon can withstand wear and provide very smooth connections. Different cheaper material like HDPE (High Density Polyethylene) bushings starts wearing resulting in compliance in the suspension mechanism connections. In order to avoid any risks, Bronze oil impregnated is used to make the bushings, this material has a much higher wear resistance yet at the same time it is much heavier.Another bushing material used isPOM (Polyoxymethylene). This material properties are- High abrasion resistance Low coefficient of friction High heat resistance Good electrical and dielectric properties Low water absorptionDelrin Properties- High tensile strength stiffness and creep resistance Significantly outperform higher resistance Allowing for thinner and lighter part design Offers outstanding low and high temperature performance Good colourability Good mating with metal and other polymer.