Inquiry (采购产品): spiral pipes I am student of metal forming engineering and I have a research about spiral pipes.I found your site as one of the best, but I have a question if you guide me to find some thing about that I will be so happy. my question: after manufacturing the spiral pipes( for gas and oil transfer) , they have a little error in the dimensions(about 1% in 56in), to improve them, some companies use the cold expanding method to decrease ovality shape but some times this action take the pipe to the more dimensional errors(about 3% )!!!!! I like to understand why this work isn't true?and which method do you prefer? and also if it is possible please intoduce me other methods of manufacture of pipes to pretty exact circumferential dimensions **** Hidden Message ***** farnoosh forouzan NZL Company: non E-mail: forouzan_iut@yahoo.com **** Hidden Message ***** forouzan_iut@yahoo.com
