b'Plain Bearing Components I NCHComponentSelectionSelecting theCorrect ComponentsGuide Pins1. Calculate L using one of the following formulas:L = T - (U + Z) for assembly with sleeve bushingsL = T - (U + Z) - J + Efor demountable bushings2. For straight pins, select a length equal to L. If L is not a standardlength, choose a longer pin and cut to L, or choose a shorter lengthand recess the pin in the punch holder to L, making sure that theminimum press t length is at least equal to the pin diameter.3. For demountable pins, select a length so that K + F is as close aspossible to L without exceeding it.BushingsGuide Pin Length Selection 1. If the tools working stroke is short and there are no off-center loads,select the shortest bushing which will produce the desired operatingcondition. Turn to the selection chart on pages 26 and 27, nd thestroke, and read down that column until it intersects the operatingcondition you have selected. The bushing you need is listed on thatline.2. When rigidity and resistance to side load are required, use theselection chart to choose the longest bushing consistent with thedesired operating condition.CAUTION: Make sure the top of the bushing does not strike thepunch holder or the demountable pin clamp screw, either when thedie is new or die life is depleted. If it does, select the next shorterbushing.Cages1. The page 26-27 selection chart automatically gives you the correctcage. It is listed on the same line as the bushing you have selected.2. Different combinations of cages and bushings are possible, but thenthe selection chart does not apply. You will need to make a layout ofthe cage travel from the start of preload to bottom stroke. This guregives you the position of the guide pin, bushing, and cage at thestart of preload. From that point on, the cage travels half thedistance of the guide pin.17'