Analysis of the causes of appearance drag of injection products

The appearance of injection molding products is strained. Some companies call it Lahua. There are many deep cavity products such as chargers, routers, chassis and other products. It is also a particularly common thorny problem in the product injection molding process. It is one of the ten most difficult problems in the mold and injection molding industry. Glossy products will pull flowers, and those with textured sides will strain the textured surface. What is hidden in this? When it comes to the surface strain, the first thing the engineer thinks is that the draft angle on the side of the product is not large enough. In fact, the reasons for the appearance strain are mainly as follows:

1. Product draft angle problem

The main problem of the product is that the draft angle of the product is too small, causing the side of the product to be dragged. Corresponding to the different grain surface requirements on the side of the product, we already have relevant experience, and most engineers have the ability to judge the draft angle of what specification grain surface should have. Solving such problems must be avoided in the early product evaluation stage. If the customer's product does not allow enough draft angle, the mold engineer must not take risks, and must consider using other technical means such as mold mechanisms to avoid it.

connector mold

2.Die Design Issues

 Parting surface

For the treatment of rounded corners, product designers often go directly to the rounded corners on the product when designing products, which is actually an unreasonable design, because the draft angle at the contact between the rounded corners and the surface is close to zero, which is easy to pull flowers, so the mold design The teacher needs to modify the product, change it to polyline connection, and use the software's draft analysis to modify the draft angle to be enough.

Mold structure

Focus on the three-level positioning problem of the mold
The first-level positioning refers to the positioning of the mold guide posts.
Secondary positioning refers to the positioning of the mold base positioning block.
The three-level positioning refers to the precise positioning such as the tiger's mouth designed on the mold core.

pencil sharpener mold

3. Mould gate
When designing the mold, it is necessary to consider the gate design so as not to cause excessive pressure on the product and cause side strain on the product. The gate should be kept as far away as possible from the side bite surface, because the pressure at the gate is large and the pressure holding time is long, and the product has a large holding force. easy to strain

In short, considering the main factors that affect the sidewall of the product, the main factors that affect the bite of the surface of the product are the above. Only by taking each step carefully, the headache of dragging the product can be avoided.