stainless steel pipe compression fittings

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The forming of stainless steel pipe compression fittings is a relatively complicated production process, which needs to be welded according to the different uses and materials of the products. The forming of stainless steel compression fittings needs to be carried out according to certain procedures, and the forming needs to be gradually formed under a certain pressure. It is necessary to strictly abide by the corresponding process, otherwise the stainless steel pipe compression fittings produced may have certain quality problems. What is the single compression of the compression fittings? What is dual card pressure? What is the difference between them before?