how to change collimating lens on SUP21S fiber laser welding gun

We official establish our factory in early 2010. At present our factory cover 12000 m2 with worker more than 120 staff. We produce CNC fiber laser cutting machine, CNC fiber laser welding machine, CNC fiber laser cleaning machine, CNC digital oscillating knife cutting machine, CNC CO2 laser machine, CNC router,etc. With more than 20 years industry experience in this field, we are famous for OEM/ODM manufacturer in China. We can design your machine, we can logo your own macine with different color, different style, different design, different functions. Machine quality is quite steady with reasonable market price. Among all old factories, our machine is of the highest cost effective. Software is easy and simple to operate. Aftersales documents is sufficient. Aftersales service is in time. Welcome to visit our factory Main produce CNC machines: etc.