Axle Type Mechanical
According to its shape, the shaft can be classified on the common straight shaft, crank shaft as the main shaft of a piston engine. Flexible shaft to the transmission power so that there is little freedom for a change in direction. To plan a shaft, it – the following should be noted
a. Above the Axis powers Withstand Load
A transmission shaft can undergo torsional or bending load or a combination of twisting and bending as has been mentioned above. There is also a shaft receiving tensile or pressure loads such as propeller shaft – boat propellers or turbines, etc. Fatigue, impact or influence of stress concentration when the shaft diameter is reduced (stepped shaft) or if the shaft has a keyway, must be considered. A shaft should be planned to be strong enough to support the weight above.
b. Axis powers Adjusted With Various Machines
Although a shaft has sufficient strength but if bending or deflection puntirnya too large will result in non-carefully situations (on machine tools) or vibration and sound (eg turbine and gear box). Therefore in addition to the strength of the shaft, its strength should also be considered and adapted to the kind of machine that will be served shaft tersebuut.
c. Critical round
When the engine is increased suata round then in a certain round price can occur vibrations enormous. This round disebur critical round. It can terjaid on the turbine, piston motors, electric motors, etc. And may result in damage to the shaft and parts – other parts. If possible, the shaft should be planned in such a way that its rotation is lower than the critical rotation.
d. Corrosion
Materials – corrosion resistant materials (plastic termasauk) must be selected and the pump when the propeller shaft comes in contact with the corrosive fluid. Similarly to the shaft of threatened cavity, and the axes machines often stopped for long. Extent – a certain limit can also be done protection against corrosion.
e. Shaft Material
Shaft for general machinery a rule made of steel rod cold drawn and defines, carbon steel construction machines (called material SC) resulting from ingot which “kill” (steel dideoksidasikan with ferrosilicon and casted; the carbon content is assured) however, the material This kelurusannya somewhat less fixed and can reduce deformation due to stress less balanced for example, when given the keyway, because there are residual stresses in the terrace.
But the withdrawal of the cold makes the shaft surface becomes hard dankekuatannya grow. Price – the price contained in the table is obtained from percobbaan rod with a diameter of 25 mm; in this case it should be remembered that for the shaft diameter is much larger fdari 25 mm, the price – the price will be lower than at present in the table because of the influence of time.
Shaft – the shaft used to carry high speed and heavy loads are generally made of steel alloy with pengerasn skin that is highly resistant to wear and tear.
Axis – the axis that looks difficult as the crankshaft, cast iron castings nodal or others have been used. Table 3.2 Shaft Material
Some of them are nickel chromium steel, nickel chromium molybdenum steel, chrome steel, chrome molybdenum steel, etc. Notwithstanding the use of special alloy steel is not recommended if the only reason for high speed and heavy load. In such case to consider the use of carbon steel heat-treated appropriately to obtain the required strength. Empa steel (G3201, forged from ingots dikil and called material SF, the power guaranteed) are also often used.
