What is called water assisted injection mould?

Water injection is similar of gas-assisted injection molding process of two steps: first step, cavity is completely melt filling;In the second step,inject water form the empty cavity.

Water injection mould generally more expensive than the gas-assisted mold, the reason is that different steel used in the manufacture of moulds.Water used in the injection mould steel higher quality (strong nickel plating layer or titanium nitride coating for the protection of water injection mold from corrosion is essential).

Points for water assisted mould making:
1.The design of the water injection equipment must satisfy the conditions of close to gas-assisted injection molding.
2.Drainage compared with exclusion of nitrogen is more complex, needs to be done by gravity and ventilation with compressed gas "discharge" of plastic parts.
3.In order to prevent corrosion, water must not be in contact with the mould surface.
4.Water injection to high water injection capacity to ensure uniform wall thickness distribution and high surface quality.

Written by Tina
skype:anole-01
Mail:serve@sinomould.com

Difference between gas assisted and water assisted injection mold

Gas-assisted injection molding technology is used in the production of rod type components to reduce part weight and cycle time.As a very mature technology has been applied in plastic processing industry many years.And the technology is one of the most important application field of thick wall plastic parts production.Gas-assisted injection molding can also help greatly reduce or eliminate flat piece area of the wall thickness,deformation and shrinkage mark,so as to improve the quality of plastic parts.

Water assisted injection is water instead of nitrogen,will make the mold cavity surface quality better.Water of the thermal conductivity is about 40 times that of the nitrogen gas,heat capacity is four times that of nitrogen.In addition to the ordinary mold cooling,water injection will make plastic parts internal cooling, compared with gas,cooling time reduced 70%,ejection temperature reach to required much faster.At the same time,water is a kind of incompressible medium and low price.In addition to processing more parts,water injection to form more uniform wall thickness,reduces the residual wall thickness.

They are without any different in the machine use,but differ on the mold design and process control.Water assisted injection mould generally more expensive than the gas-assisted mold,the reason is that different steel used in the manufacture of moulds.Water injection molding steel material hardness more hard than gas-assisted injection mould.
Written by Tina
Skype:anole-01

Mail:serve@sinomould.com