le ▁edge ▁of ▁the ▁hole . ▁Lub ric ation ▁area : ▁its ▁role ▁is ▁to ▁store ▁lub ric ant ▁which ▁is ▁condu ci ve ▁to ▁lub ric ate ▁drawing ▁materials ▁so ▁that ▁the ▁drawing ▁process ▁can ▁be ▁completed ▁successfully . ▁Working ▁area : ▁Working ▁area ▁is ▁the ▁pl ast ically ▁de form ing ▁area ▁for ▁drawing ▁materials . ▁L ength ▁and ▁cone ▁angle ▁are ▁the ▁two ▁factors ▁for ▁the ▁working ▁performance ▁of ▁this ▁area . ▁If ▁the ▁working ▁area ▁is ▁too ▁short , ▁excess ive ▁pressure ▁to ▁the ▁working ▁area ▁will ▁be ▁generated ▁by ▁the ▁metal ▁stretch ed . ▁For ▁the ▁above ▁reason , ▁the ▁tens ile ▁stress ▁increased ▁significantly , ▁resulting ▁in ▁the ▁acceler ated ▁wear ▁of ▁the ▁m old . ▁The ▁principles ▁for ▁the ▁selection ▁of ▁the ▁length ▁of ▁the ▁working ▁area ▁are ▁as ▁follows : ▁a . ▁The ▁working ▁area ▁used ▁for ▁stretch ing ▁soft ▁metal ▁wire ▁is ▁shorter ▁than ▁the ▁working ▁area ▁used ▁for ▁stretch ing ▁hard ▁metal ▁wire ; ▁b . ▁The ▁working ▁area ▁used ▁for ▁stretch ing ▁metal ▁wire ▁with ▁small ▁diameter ▁is ▁shorter ▁than ▁the ▁working ▁area ▁used ▁for ▁stretch ing ▁metal ▁wire ▁with ▁a ▁large ▁diameter ; ▁c . ▁The ▁working ▁area ▁worked ▁under ▁the ▁condition ▁of ▁wet ▁lub ric ation ▁is ▁shorter ▁than ▁the ▁working ▁area ▁worked ▁under ▁the ▁condition ▁of ▁dry ▁lub ric ation . ▁As ▁for ▁the ▁t aper ▁angle , ▁the ▁t aper ▁angle ▁is ▁smaller ▁when ▁stretch ing ▁steel , ▁while ▁the ▁cone ▁angle ▁should ▁be ▁larger ▁when ▁stretch ing