How does the auto parts mold factory design the door handle mold?

The quality of the inner door handles is particularly important to the auto parts mold factory.

The inner handles of car door locks are all electroplated or painted after injection molding to increase their aesthetics and improve the fit between the car handles and the car body and interior and exterior decorations. It is this demand that puts higher requirements on the molding quality of plastic parts, and polished chrome plating is required. The basic requirements for plastic parts are: smooth surface transition, no pores, weld marks, cold material marks and other defects that affect function and appearance are allowed.

The shapes of door handles in cars include long strips and buckle door handles, among which long strip door handles are preferred by most car OEMs. Long strip door handles are slender and are easier to be broken than buckle door handles of the same material. In terms of material selection, long strip door handles need to consider choosing materials with higher strength, such as electroplated PA; buckle door handles generally choose materials with lower strength requirements, such as electroplated PC/ABS.

Design details of the door handle mold in the auto parts mold factory

It is known that in most cases, the material of the door handle is PC/ABS, which is very suitable for electroplating and has a shrinkage rate of 1.005.

First, the designers of the auto parts mold factory need to analyze the shape of the outer handle of the automobile door lock and conduct a feasibility analysis on its injection mold structure.

According to the production volume and mold life required by the customer, decide which steel to use, set the number of mold cavities, and whether to use a hot runner.

Each car has four handles, so the handles are used in large quantities, and the mold is generally made of multiple cavities, such as 4 cavities.

Since the handle is made of PC/ABS, and in order to increase mechanical strength, the PC content is generally higher than ABS, so the molding temperature is higher, so a perfect cooling system needs to be designed.

The cooling system consists of pipes and screw plugs, pipe joints, sealing rings and spacers in the fixed and movable molds. The mold frame consists of the fixed mold plate, fixed mold base plate, movable mold plate, cushion block, push rod fixing plate, push plate, movable mold base plate, guide sleeve and guide column.

Heat treatment and surface treatment of mold parts

To ensure the dimensional accuracy and surface quality of the inner handle, the main parts of the mold, such as the fixed mold insert, the movable mold insert, the inclined slider, the smooth block, etc., are made of S136 steel with a heat treatment hardness of 50-54HRC, and the surface is coated. For general structural parts, the economy should be fully considered, and the actual use frequency of the mold and the final plastic parts batch should be flexibly processed. For example, the slider and the side core are all made of 718 or H13 for appropriate heat treatment.

Mold Trial and Improvement

For the inner handle mold with high requirements on size and appearance, factors such as shrinkage control, demolding angle and gate position can be predicted in advance through mold flow analysis in the early design of the mold, but the mold exhaust setting, overflow chute setting, mold temperature control and related injection molding parameter settings all need to be continuously adjusted and improved during the mold trial process.

Yuanfang Mold is auto parts mold factory. It also produces injection moulding products on a contract basis. Injection moulds are mainly for automobiles, home appliances, medical equipment, daily necessities, and front and rear bumpers, front and rear lights, internal and external handles, etc. in automotive parts.

The company has been established for nearly ten years and has accumulated rich experience in injection moulds from product concept design to process processing, mould structure, and injection moulding production. It has also made continuous innovations in the gate, runner, cooling water channel, internal and external core pulling, slider, molding cycle and other technologies of large moulds.