Industry and solutions(Plating industry,Auto industry,Appliance industry)
Ø industries we served : 3C digital appliance , Home appliance , Automobile , Plating industry , Etc.
Ø Solution : Eliminate injection parts shrinkage , Welding line , Reduce cracks ,Floating fiber ,Flow mark , Stress mark and could eliminate hot runner mark and make injection part perfect.
Injection welding lines
Ø General injection moulding issues: Shrinkage , Sliver streak , Burn marks , Rough selvedge , Vent mark,Crack , Stress mark , Floating fiber , Warpage , Welding lines Etc.
Ø Crack , Stress mark , Floating Fiber , Warpage , Welding mark Etc. These issues can not be settled byinjection parameters adjustment or mold structure improvement , These issues could be settled by change moulding temperature only.
Ø Welding lines forming:For injection moulding , to meet injection moulding condition, Multi-direction runners are needed .During injection process, melt resin flows inside cavities, when melt resin meets the cold mold core. melt resin temperature drops gradually , at the final confluence, the melt resin does not fully coalesce due to temperature inconsistencies(below the TG point)
Rapid heating and cooling injection
Ø Working principle : 4 processing stages 1.Mold heating 2. Mold high temperature maintaining 3. Cooling and pressure maintaining 4. Miscellaneous media removal.
Ø High temperature and high pressure steam are blown into mold cavity , mold cavity temperature rises rapidly ,when temperature of mold cavity reach glass transition temperature(TG)instantly . injecting melt resin (As mold cavity is in high temperature , the flowability of resin is good in mold cavity and easy to integrate) into mould cavity , Then keep the pressure and cool down the mold (during the cooling down processing , vapor temperature control system simultaneously doing the miscellaneous media removal work for next production cycle) , after
cooling down work done and resin is moulded . Mold will be open and the part could be taken out , thus one high glossy part with perfect surface production completed
(Small mold ) 10---20 Sec. 20--35 Sec.
(Big mold) 20—30Sec 20----40Sec.
Advantage of rapid heating and cooling mold
Ø 1:Rapid heating an cooling molds need use heat-resisting and good conductivity steel to meet fierce temperature change.
Ø 2:Mold water ways should avoid using water proof ring , it is better water connectors directly connect to mold cores to reduce heat dispersion and guarantee safety during injection.
Ø 3:Inner surface of mold need very high finishing to ensure mirror effect surface of plastic part.
Ø 4:Waterways design inside mold should be reasonable and even distribution . and water ways quantity need ensure mold core's rapid heating and cooling.(Proper distance between waterways and mold core is very critical also)
Ø 5:Special attention to the maintenance of molds should be paid after injection production , molds should be kept dry and dust free
Rapid heating and cooling mold achieve mirror effect
Waterways should be designed along with the shape and even distribution.Part production total cycle time is 40 Sec.
Rapid heating and cooling injection technology features and advantages.
Ø 1.Eliminate welding line , Shrinkage mark and flow mark.
Ø 2.Enhance the gloss on the surface of parts , so as to achieve mirror , high-black and high gloss effect ,completely solve the plastic part shrinkage issue.
Ø 3.Improve the tensile , compressive strength and surface anti-scratch performance.
Ø 4. Reduce subsequent processing procedures(such as painting and electroplating) increase yield by 20-30%
Ø Eliminate floating fiber surface of glass fiber parts. Thin wall forming can improve of molding fluidity .Improve product quality and strength ,and reduce the injection cycle of thick wall moulding by more than 40%.
Ø 6. For electroplate parts, it can improve part mirror effect, eliminate the welding lines , reduce the crack mark of parts to be plated and the defective rate of plating production.
Ø 7.Eliminate parts stress mark, release internal stress of parts , improve rib marks of texture parts .
Ø 8. Reduce injection pressure and prolong injection machine's lifespan.
Ø 9.Eliminate hot runner mark and make injection part more perfect.
more information will be update next time!