In fact, there is no need for inserts in the ideal design. It is better to be machined at one time. However, some shapes are too complex to be machined, which is easy to be machined but not easy to be maintained. For example, if it is a bit damaged, only the inserts can be repaired. If it is a whole, if repair welding is required, other profile surfaces will be changed.
Some big mould enterprises have been pursuing no insert at the beginning, but in the end, it still needs specific situation and specific analysis. The biggest disadvantage of inserts is that they reduce the strength of the mould itself, but they can use different materials to increase the strength of the weak parts separately.
Let’s see what inserts are required:
1. Material saving: the fixed material of the back die is determined by the highest point. If it is only a single high part with regular shape, this block can be inlaid so that the fixed height can be fixed.
2. Convenient machining: EDM is the slowest and least accurate machining equipment, so in order to avoid EDM machining, insert is selected.
3. Convenient exhaust: especially for some deep bone positions, poor fluid discharge during EDM processing and poor exhaust during molding, inserts are often required.
4. Guaranteed accuracy: The grinding machine has the highest machining accuracy. Sometimes, in order to ensure the accuracy, the convenience of the grinding machine machining shall prevail.
5. Interchange requirements: Sometimes the customer requires the same product to change the tag position for interchangeable inserts.
6. Convenience and mould saving: some deep positions are quite inconvenient for mould saving, so inserts are made.
7. Easy die change: some positions are easy to be worn or the precision is too high. For the purpose of die change, inserts are made.
8. Heat dissipation considerations: this mainly refers to beryllium copper inserts.
In terms of processing efficiency. Some big moulds are inlaid into several small parts and processed separately to save time. Generally, inserts can be divided into two types: insert through and blind insert. For some small inserts, Y-CUT line cutting can be used for positioning with hanging platform. For some large inserts, such as those above 60X60, blind inserts can be adopted, with screws hanging. Processing is relatively difficult, but the strength of the mould is guaranteed.
Insert material: insert without abrasion, the material can be the same as the core material.
If there is a rub through insert, the material may be the same as the core material, except that the hardness is increased by 2 degrees, or a material of different hardness.
Then, when designing the hanging platform, pay attention to the processing difficulty and reference position, so as to facilitate wire cutting and grinding machine processing. Generally, the hanging platform can be designed as 5X2.0MM or 4X3MM.
The hanging platform shall be placed in the straight position of the insert. As shown in the figure
The hanging platform shall be shorter than the flat edge by 0.5-2.0 for the convenience of line cutting R angle.
When the insert is special-shaped and not suitable for hanging platform, it can be inserted directly with 1-2 degree inclination around. This is the taper insert.
