PVC foam board production equipment
PVC foam board production equipment production products are mainly used in packaging, construction, doors and windows, electronics, home decoration, electrical and other industries. Its advantages are good thermal stability, corrosion resistance, anti-aging and long service life.
The unit is composed of conical (parallel) twin-screw extruder, vacuum setting table, tractor, cutter, tripper, etc. The conical (parallel) twin-screw extruder and traction machine adopt AC frequency conversion speed regulation. Vacuum pump and traction motor are of high quality. According to the profile size and wall thickness, the tractor adopts the upper and lower track traction mode. The cutting machine can select saw blade type cutting, with length measuring device. The unit has reliable performance and high production efficiency.
The production line is divided into two types: automatic control and manual control, which can be produced on demand according to production needs.
Mold: the precise flow channel and reasonable foam cavity design of the mold can make the fluid disperse evenly and ensure the consistent extrusion speed of raw materials. Extruder: the use of hard tooth reducer, the advantages of long service life, high stability, low noise. It is reliable in quality and high in stability. Special screw and water cooling system are used to ensure the stability and output of the extruder.
Vacuum setting platform: high efficiency vacuum setting mold is used to ensure the profile molding degree and speed. The setting mold is made of high-quality mold steel, and the platform is made of 304 stainless steel plate. The platform is equipped with negative pressure vacuum dingna system, as well as water cooling system. Vacuum pump and water pump are all domestic famous brands.
Cutting machine: pneumatic control, special clamp and alloy blade are used to ensure the length of profile and the flatness of incision during profile cutting.
Traction machine: adopt the whole transmission system and special traction fixture to increase the stability of traction machine and prevent the traction machine from losing step.
Introduction to the vacuum pump used in the production of PVC foam board:
Liquid ring pump of over compression and under compression of phenomenon and solution
1. Over compression phenomenon: the closed small cavity does not reach the exhaust port, and the gas in it has reached the exhaust pressure (usually occurs in the large pump, and is easy to occur when the suction pressure is high);
2. Insufficient compression: the closed chamber is connected with the exhaust port, but the gas in it has not reached the exhaust pressure (usually occurs when the suction pressure is low).
All of the above phenomena are related to the change of suction gas pressure, while the position (compression ratio) of the two ports of the pump is fixed.
Bring problems: consume more power (waste energy), reduce the pumping efficiency of the pump.
Solutions to problems
1. A rubber ball valve is arranged in front of the exhaust port: when the gas in the small chamber reaches the exhaust pressure too early, the ball valve opens.
2. Adopt flexible exhaust valve design (patent) to avoid over compression. The flexible exhaust valve reduces the energy consumption of the pump by automatically adjusting the exhaust area. So as to achieve the best operation efficiency.
3. In design, the minimum suction pressure (limit pressure) is used to determine the compression ratio (exhaust port position) of the pump
Compression ratio = P out / P in = V in / V out
Design time: P in and out limit pressure