Nanjing Useon Extrusion Equipment Co., Ltd.

EVA solar battery separator/film direct extrusion line had been tested successfully by the end of May

After PC sheet direct extrusion line, EVA film direct extrusion production line was our 2nd delivered complete direct sheet/film extrusion line in May 2010. This line was consisted of gravimetric feeding system, TDS75 twin screw extruders, gear pump, T-die, calenders, haul-off, winder, cutting system and in-line thickness tester. The final product of EVA film from this line supposes to serve as solar battery separator/film.
Comparing with traditional process that the resin will be pre-compounded in twin screw extruder and then put it into single screw extruder for molding extrusion, in-line compounding direct extrusion process is becoming more popular. There are a lot of remarkable advantages about direct extrusion process. It is summarized as two aspects, one is economic, and another is technology.
 You don’t have to buy pre-compounded pellets from market. Compounding process has been integrated with direct extrusion line;
 You don’t have to buy two lines for compounding and molding extrusion;
 Save materials turn-over time and energy consumption;
 Save labor cost for two stages process;
 Speed up your research circle: Your technicians can adjust formulations in-line any time, after then they can observe the results just tens of minutes later;
 Shorten thermal and shear history of raw materials: As the line integrated compounding and molding extrusion into once step so that the materials don’t have to be reprocessed again.
 Keep your knowhow confidential: As you control all formulations of each ingredient yourself, so you are not dominated by pre-compounded material suppliers any longer.
Although in-line compounding direct extrusion has many advantages, actually some of the materials that have benefitted from direct extrusion include, but are not limited to, filled olefins, TPE/TPO/TPV’s, polyesters, PVB, wood-fiber composites and so on, it is not so good to everyone. The complete line of in-line compounding direct extrusion is more complex than either twin screw extruder compounding pelletizing line or single screw extruder molding extrusion. You need knowhow about compounding of polymers. And the initial investment bar is also higher than single screw extruder molding extrusion.
As twin screw extruder is starved feeding, the fluctuation of feeding rate will result in extrusion pressure at die exit, so generally volumetric feeders are not acceptable in direct extrusion, you need gravimetric feeder for each ingredient. To shorten the L/D ration and establish stable extrusion pressure, gear pump is often introduced into direct extrusion line. These make the line a little bit more complex. You should balance your strength and weakness before your decision. However, in-line compounding direct extrusion is a kind of advanced extrusion process.
To learn more about in-line compounding direct extrusion, please feel free to contact us. Our team is glad to help you.