Runner/Gate (Check list for mold design)

 The column in this issue is the check list in the design of injection molding mold, runner/gate.


Injection molding molds must have runners and gates, which are used as channels for injecting the plastic used as the molding material into the mold after melting.


The following are design inspection items related to runners and gates.


(1) Is it necessary to do runner equalization?


(2) Does the diameter of the tip of the gate match the diameter of the injection nozzle of the molding machine?


(3) Does the thickness of the nozzle meet the flow requirements?


(4) Is the cross-sectional shape of the runner appropriate?


(5) What is the cross-sectional area of the flow channel?


(6) What is the average hydraulic radius of the runner?


(7) What is the weight of the runner?


(8) Do you need runner material?


(9) Is the relationship between the position of the runner material and the gate appropriate?


(10) Can the runner be demolded smoothly?


(11) Can the runner be pushed out smoothly?


(12) What is the method of taking out the runner? (free fall, take out the robot (direction))


(13) Is the gate position appropriate?


(14) Is the number of gates appropriate?


(15) Is the gate method appropriate?


(16) Can the location of the weld line be predicted?


(17) Can the location of dents be predicted?


(18) What is the cross-sectional size of the gate?


(19) Is the gate cutting method clear?


(20) Is it possible to perform quality control after gate cutting?


(21) How many injections is the design life of the gate?


(22) Does the gate part need to be pre-divided into separate parts?


(23) Is the machining dimension measurement method of the gate clear?


(24) What is the mold material of the gate part?


(25) What is the hardness of the gate part?

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