Equipment and method for preparing polytetrafluoroethylene (PTFE) membrane by three-dimensional (3D) stretching

• Main Authors: HUANG BINXIANG, HUANG LEI, WU JIANLIN, MA TIAN, YANG YUAN, HAO XINMIN
• Format: Patent
• Language: Chinese; English
• Published: 04.01.2012
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

The invention relates to equipment and a method for preparing a polytetrafluoroethylene (PTFE) membrane by three-dimensional (3D) stretching. The equipment comprises a base-band feeding unit, a longitudinal stretching unit, a transverse expanding and stretching unit, a curing and shaping unit and a cooling unit. The equipment is characterized in that: an arc stretching unit is arranged between the longitudinal stretching unit and the transverse expanding and stretching unit, and the arc stretching unit comprises multiple thermotanks which are identical with the longitudinal stretching unit; each thermotank is internally equipped with multiple olivary roller wheels; each roller wheel has two thin ends and one thick middle part; an angle alpha between a central axis of each roller wheel anda tangential line of a convex part in the middle of each roller wheel is 0-75 degrees; and the angle alpha between the central axis of each roller wheel and the tangential line of the convex positionin the middle of each roll