Machine Parts

(I).    High load carrying capacity. (II). High rigity. (III).                       Longer life (IV).                      Easy heat removal by oil leakage. (V).                         No variation of friction force because there is no metal to metal contact. (VI).                      Dust and metallic microelements are flashed away by oil forces. <![endif]--> Determine the actual diameter for drawing   a cup of 2- inch diameter having 2- inch depth and corner radius 1/6 – inch. If the material is 1/32 –inch thick also determine radius of Punch and Die.        Solution : Given data, d=2˝, h=2˝, r=1/10˝, t=1/32˝ The ratio   =   =32>20 D= 2 +4dh) = 2 +4*2*2) =4.47 ˝ According to the general rule for adding 1/8 to the blank diameter for each inch of cup diameter 2*1/8 =1/4  So, D=4.47+0.25=4.72˝ The radius is 4 times of the material th

 Difference between hydrostatic slide ways and hydrodynamic slide ways are given below Hydrostatic slide ways Hydrodynamic slide ways Liquid friction condition of the interface of mating surface are achieved by supplying under pressure. Liquid friction condition between sliding surfaces are achived due to Hydrodynamic action. Sliding bodies must not be inclined to each other. Sliding bodies must be inclined each other. Possiblity of all sliding speed including zero speed. Possiblity of high sliding speed. Used in high expensive machine. Used in low expensive machine. Example: Grinding programmed controled & coppying machine.  Example: verticle boring & planning machine.

  Condition of a shallow drawing operation :   “The cup is no deeper than half its diameter” is the condition of a shallow drawing operation. Double action draw die:   When the die is designed for a double action press with the blank holder fastened to the outer ram, which descends first and grip the blank then the die is known as double action draw die. The punch is fastened to the inner ram, which descends next to form the part.  The cup may be pushed through the die or ejected back through the die by use of a knockout actuated by an air cushion. The knockout may also be used to hold the blank firmly against the punch nose during the punch operation.