General FAQs
Answer 1.
Answer 2
Answer 3
Support FAQs
| Possible Cause | Suggested Remedy |
| Overpacking material in mould | a. Decrease first stage injection pressure b. Decrease boost time c. Decrease injection forward time d. Decrease packing pressure e. Increase injection transfer position (to lower injection peak pressure) |
| Improper finish on mould | Draw polish mould to proper finish |
| Insufficient draft on cavities and sprue | Polish and provide maximum allowable draft |
| Knockout system poorly designed | a. Redesign knockout system for balanced ejection forces b. Review operation of knockout system, plates not opening in proper sequence |
| Core shifting and cavity misalignment | a. Realign cavities and cores b. Add interlocks to mould halves |
| Undercuts in mould and possible surface imperfections | a. Repair and polish b. If undercut is intentional, redesign or reduce |
| Non-uniform cavity pressure in multi-cavity mould | Redesign runners and gates for balanced filling of cavities |
| Moulded parts too hot for ejection | a. Increase cooling time b. Decrease melt temperature c. Decrease mould temperature |
| Moulded parts sticking to stationary half of mould | a. Redesign sprue puller b. Apply mould release c. Increase nozzle temperature d. If parts remain on wrong side of mould, undercut other side or try differential mould temperatures |
| Possible Cause | Suggested Remedy |
| Melt temperature too low | Increase melt temperature |
| Mould temperature too cold | Increase mould temperature |
| Injection pressure too low | a. Increase first stage pressure b. Increase boost time c. Increase injection speed |
| Insufficient feed | a. Increase shot size to maintain a constant cushion b. Inspect non-return valve for wear |
| Insufficient injection forward time | a. Increase injection forward time b. Increase injection rate |
| Entrapped air causing resistance to fill | a. Provide proper venting b. Increase number and size of vents |
| Restricted flow of material to cavity | a. Increase gate size b. Increase runner size c. Use nozzle with larger orifice |
| Unbalanced flow to cavity in multi-cavity mould | a. Increase gate size b. Redesign runner to provide balanced flow |
| Possible Cause | Suggested Remedy |
| Material too hot | a. Decrease melt temperature b. Decrease mould temperature c. Lengthen cycle time |
| Injection pressure too high | a. Decrease injection pressure b. Decrease boost time c. Decrease injection rate d. Increase transfer position (to lower injection peak pressure) |
| Excessive packing of material in cavities | Decrease packing pressure |
| Projected area too large for available clamping force | Use larger tonnage machine |
| Mould clamping pressure not properly adjusted | a. Increase clamping pressure b. Check mould parting line for obstruction c. Check platen parallelism |
| Uneven or poor parting line and mating surfaces | a. Remove mould, carefully inspect and repair parting lines, cavities and cores which do not have positive shut off b. Add support for mould cores and cavities |
| Non-uniform cavity pressure due to unbalanced filling | a. Balance/increase runner and gate sizes to obtain uniform filling b. Properly balance cavity layout for maintaining uniform cavity pressure |