What are the basic characteristics of mould machining?

Mold Making refers to the processing of forming and blanking tools, in addition to shearing and die-cutting dies. Normally, a mould consists of an upper and a lower die. A steel plate is placed between the upper and lower dies and the material is formed under the action of a press. When the press is opened, the workpiece defined by the shape of the die is obtained or the corresponding scrap is removed. Workpieces as small as an electronic connector or as large as an automotive dashboard can be formed in a mould. A progressive die is a set of dies that automatically moves the machined workpiece from one station to another and obtains the formed part at the last station. The tooling process includes: cutting dies, blanking dies, compound dies, extrusion dies, four-slide dies, progressive dies, stamping dies, die-cutting dies, etc.

(1) High processing accuracy requirements A pair of moulds is generally composed of concave die, convex die and die frame, some may also be multi-piece collocation module. So the combination of upper and lower moulds, the combination of inserts and cavities, and the combination between modules all require high processing accuracy. The dimensional accuracy of precision moulds often reaches the μm level.

(2) Complex surfaces Some products such as car covers, aircraft parts, toys, household appliances, the shape of the surface is a combination of a variety of surfaces, therefore, the mould cavity surface is very complex. Some surfaces must be processed by mathematical calculation methods.

(3) Small batch sizes Moulds are not produced in large batches, and in many cases are often produced in a single batch.

(4) Many processes Milling, boring, drilling, reaming and threading are always used in the machining of moulds.

(5) Repetitive production The use of moulds has a life span. When the use of a mould exceeds its life, it must be replaced with a new mould, so the production of moulds is often repetitive.

(6) Imitation processing Sometimes there are neither drawings nor data in the production of moulds, and they have to be imitated according to the real object. This requires a high precision of imitation and no deformation.

(7) excellent mould material, high hardness The main material of the mould is mostly made of high quality alloy steel, especially the high life of the mould, often using Crl2, CrWMn and other Leyland steel manufacturing. This kind of steel from the blank forging, processing to heat treatment are strict requirements. Therefore, the preparation of the processing process should not be ignored, heat treatment deformation is also a problem that needs to be taken seriously in processing.

According to the above-mentioned many characteristics, in the selection of machine tools to meet the processing requirements as far as possible. Such as the function of the CNC system to be strong, machine accuracy to be high, rigidity, thermal stability to be good, with the imitation function.