SU780947A1 - Method of production injection mould inserts - Google Patents

Description

(54) METHOD OF MANUFACTURING INSERTS PRESS-FBRM The invention relates to foundry, in particular, to the technology of molds with thin-walled shell forming parts, and specifically to methods of fastening thin-walled inserts in the holder of molds. One of the most efficient areas of application is the fastening of the inserts made by the method of electroforming and plasma spraying. Molds with such inserts are used in the manufacture of the widest range of plastic products and other materials. . Methods are known for fastening an electroplating forming insert: mechanical, by soldering and Adhesive 13. Each of these methods is used with corresponding products of a non-wear configuration. However, mounting a talvanoplastic insert with a hard-faced profile is very difficult or impossible. Known methods of fastening the casing with balls and rods jf. But this method does not ensure uniform distribution of the load on the supporting surface from the side of the supporting layer. Moreover, the shells obtained by methods of electroforming and plasma spraying are characterized by the presence of irregularities and undercuts on the outer side of the insert. Experimental work on fastening complex galvanoplastic inserts of molds by pouring with different alloys with low melting temperature (before) or plastic compositions is known. H. With fusible alloy casting methods, the small hardness and strength of the support layer leads to premature wear of the insert due to shrinkage of the cast alloy the shear and cracking of the shells often occur, and the cost of low-melting alloys is also high. Methods for fastening inserts with plastic compositions (epoxy: compound) have the same drawbacks. In addition, the low thermal conductivity of the support layer worsens the pressing conditions, which reduces productivity and leads to premature wear of the insert.

The purpose of the invention is to increase the durability of the mold inserts by creating a uniform distribution over: the OnOiSHOro layer onto the bearing surface of the thin-walled shell with undercuts and simplifying the manufacture of the inserts.

This goal is achieved by the fact that under the action of the magnetic field of the undercut of the thin-walled form-m. the expanding shells are filled with balls, covered with a bonding material with solder, epoxy compound).

FIG. 1 shows schematically an installation for preheating the forming shell} in FIG. 2 shows a method for filling the undercuts of a shell and making a forming insert.

The proposed method of manufacturing the insert is carried out in the following technological sequence.

In a known manner (by electroplating or plasma spraying), a thin-walled forming shell 1 is produced according to the model, which is processed according to size 1 in accordance with the process dimensions of the process sleeve 2. The shell 1 with the previously treated non-working surface is placed in the process window 2 and assembled into the bath 3 sand 4.

The bath 3 with the shell 1 is heated to the melting point of the solder on the electric stove 5, after which it is installed on the magnetic stand 6. The bath 3 with sand 4 provides uniform heating of the shell 1 and allows heat to be stored for the time required for further technological operations.

Steel balls of 7 different fractions (1-4 mm in diameter) are prepared and maintained.

The serviced and heated balls 7 are poured into the cage 2. With ngshichii on the non-working surface of the shell 1 undercuts; The balls of 7 small fractions (01 mm) are pre-filled to fill them up. The balls 7 are distributed manually, and the magnetic field created by the stand 6 holds them both in the undercuts and on the vertical walls of the shell 1. Then, before alignment of the support, balls 7 of larger fractions fall asleep (f (2-4 v

The magnetic field of the stand b ensures that the balls 7 are packed tightly along the entire filling volume. For better compaction of the most udzhshenny from the surface of the shell 1 sl6e & Plate 7 uses a plate 8 with apertures of 01–2 mi to enter excess binder and a load 9 (weight of 2-3 kg).

After curing of the binder, a monolithic support layer is formed. The resulting forming insert, consisting of the technological casing of the shell and the support layer (from the balls and the plate), is removed from the magnetic stand 6, removed from the bath 3 and processed according to the dimensions of the mold cage window.

In this case, the fastening of the insert in the cage of the mold can be carried out both by the sides of the casing 2 (fastening the dovetail) and by bolts on the horizontal plate 8.

In the above process, a low melting alloy is used as a binder. Plastic compositions can also be used. This eliminates the operation of the shell heating in the sand bath and maintenance.

Using the proposed method of manufacturing mold inserts Compared to existing ones, it is possible to mount thin-walled shells with any difficult-shaping forming surface with undercuts on the anchor side of the shell (to obtain a strong solid cast layer providing mechanical strength and good thermal conductivity of the insert to ensure uniform load distribution shell on the supporting layer CHBO increases the resistance of the insert, as well as reduce the complexity of manufacturing Ensuring the strength and good thermal conductivity of the insert; to ensure an even load distribution of the working surface of the shell on the support layer, which increases the resistance of the insert, as well as reduces the laboriousness of manufacturing mold inserts by expanding areas of the progressive electroforming method instead of the traditional mechanical and mechanical processing of forming inserts with deep and embossed work surfaces.

Claims (1)

Invention Formula A method of manufacturing mold inserts, including the production of a thin-walled shell, its installation into the holder and the creation of a support layer of balls, characterized in that, to simplify manufacture and increase the durability of the mold inserts in operation, the holder with the thin-walled shell is mounted on the magnetic stand and the supporting the layer is formed in a magnetic field by placing balls coated with a binding material: then it is held until the binding material is cured with the subsequent filling of the cavity with normalized elements s.