Acceptance Standards Of A Good Mold (Ⅱ)

As I talked in last news, the acceptance standards of making a good mold, today I would like to talk about another 5 principles about the standards.

5. Gating system

*the location of gate shouldn't influence the product appearance and  assemble

*the runner cross section and length should design reasonably, under the premise of forming a whole product, should decrease the cross section and length to reduce the cooling time and waste material

*the shapes of branch runner in three plate mold should be trapezoid or half round

*the gate and runner should be machined according to the drawings, and to avoid using sander by hand

*there should be an extension before brance runner to act as cold slug well, if the transparent products, the deepth and diameter of cold slug well should meet design standard

*the sprue puller should be fixed firmly and Z shape backoff should be smooth

*the brance runner on the joint face should be round shape

6. Hot runner system

*the connect line of hot runner should distribute reasonably, and one-one correspondence for easy maintenance

*before installing, should security testing the hot runner, the insulation resistance to ground should more than 2MW

*the temperature control box, hot nozzle and hot runner should use standard component

*the connect between hot runner and heating plate or heating rod should be good, the heating plate should be fixed with screw or bolt to have well fits

*better to use J type thermocouple, and match with temperature control box

*every set of heating element should be controled by thermocouples with rational distribution 

*the hot runner is fixed by at least two locating pins or add bolt to fix it

*there should be heat insulated pad between hot runner and mold plate

*the error between setting temperature in temperature control box and actual display temperature should be less than ±5℃, and sensitive on temperature control

*the connecting line should be tied up, and covered by pressing plate

*should clearly marked if there are two same size sockets, the socket should be installed on elextricity board, and can'e exceed the mold plate

*there should have sheath on control line, and have no damage

*all connect wire should fixed correctly with good insulation performance, and can't expose outside the mold

*before mold assembly, all circuit should well done, and after assembly, should check again with multimeter

7. The molding part, joint face, air venting

*there shouldn't be any defect to influence the mold surface, such as unfairness, scallops, rust, etc.

*the gapa of four corner between insert and mold frame should be less than 1mm

*the joint face should be clean and tidy

*the depth of air venting duct should be less than excessive boundary value of plastic

*inserts should be fixed firmly, and round pieces should have standstill locking, there is no copper or iron plate under insert

*if the mold is multi-cavity with left & right, should marked L & R on the place which not influence the surface and assembly with 1/8 word size, if customers have their own requirements, should make according to theirs

*if the mold is multi-cavity with same pieces, should be marked with 1, 2, 3, etc.

*the joint face, the spoting face, the insert face should be design correctly

*the sealing part should accord with standard, middle-sized should be 10-20mm, big-sized should be 30-50m

*the texture and sand blast should meet customers requirements

*the product required high requirement surface, should take preshrunk measure on bolt

*if the depth of bolt is more than 20mm, should using pipe-jacking

*the wall thickness of product should be balance, and the tolerance should less than ±0.15mm

*the insert on lifter, silder and other place should be fixed firmly

8. Injection molding process

*the injection pressure should be less than 85% of rated maximum injection pressure

*the holding pressure should be less than 80% of actual maximum injection pressure

*the injection speed shouldn't exceed the 90% of rated maxmium injection speed 

*the clamping force should be less than 90% of rated clamping force of matched injection machine

*in the process of injection, it should be easy and safety when taking out the product and gate material

*for product with insert, it should be easy and fix on installing insert

9. Packing & delivery

*cleaning the mold and paint anti-rust oil

*applying lubricating oil in sliding parts

*the feeding hole on sprue bush should be blocked with lubricating grease

*should installing the mold locking pieces with standard pieces

*the spare parts should complete, with a detailed list

*the mouth of in and out of water, gas and electric should be sealed to avoid some dirty entering

*applying oil paint on mold surface or according to customers requirements

*packed mold with film to keep away from moisture and water, then putting in the firm wooden box

*the electrinic documents(product drawings, structure drawings, cooling&heating system drawings, hot runner drawings, detailed statement of spare parts, operation instruction, mold testing reports, etc.) should be all in readiness

*taking photos to record the mold packing and delivery

Aoxu holds the principle that insist on the standards to make good quality mold, so that our customers can trust us to give us perpetual orders. If you have any project on injection mold, you can contact Shine to get inquiry.

Email: [email protected]

Phone: +86 157 5766 8880