PVC door and window 3-head welding machine 1. Main feature 1). Its three heads are contrlled by PC system and droved pneumatically. 2). Its movement stand adopts CM no-oil lubricating bearing and linear ball bearing ,so it is of high precision, easy operation and conveniet maintenance. 3). Its three heads can work individually combination of three heads. 4).One of the heads can weld various angles, which can meet the customers need of welding an arc and other special-shaped windows. 2.Main technique parameter