Diaphragm gate

Diaphragm gate Gate employed in molding tubular or annular products. 

Figure 17 (1) Diaphragm gating system through primary lip. (2) Diaphragm gating system through dirt lip.

The diaphragm gate (Figure 4-3) is employed with axially symmetrical round articles. Initially, the melt is evenly distributed across the diaphragm gate and then flows uniformly into the cavity. This method prevents weldlines, which would occur, if several gates were used. This type of gate will subsequently have to be severed however. 

The fihngate (Figure 4-4) functions to the same principle as the diaphragm gate. It is used with flat moldings and assists cavity filling. (Leaves neither weld-lines nor other markings on the article s surface). 

Diaphragm gate dl-o- fram (web gate) n. In an injection or transfer mold, a gate that forms a complete thin web across the opening of the part, used in the molding of annular and tubular objects. 

Using the diaphragm gate (Figure 1.31), round products with high rotation precision can be produced. A post-machining process is needed to separate the runner. 

For single-impression moulds which are to be produced with a central orifice, this type of gating can be used to obtain imiform radial mould filling. The diaphragm gate is removed by a subsequent machining operation. It is shown in Figure 4.20. 

---