Biopsy forceps parts are medical equipment products, used to do gastroscope stomach tissue sampling test. The products molding line shrinkage rate (16.29%-17.10%), 3D shape is complex and burr requirement within 0.03 mm, high dimensional accuracy (0.015 mm), wall thickness, only 0.3 mm, the thinnest place of tolerance size requires 100% control, mould processing accuracy reached a quite high level. If parts use of traditional processing technology, production technology is complex,and the precision is low, cannot be a molding parts, needs to be done multiple processes, the production cost is high, even difficult to achieve high accuracy and consistency required by the design of parts.
Biopsy forceps parts
3D design model
The biopsy forceps parts by MIM process,Materials of 17-4 ph,Thermoplastic system according to 90% of the metal powder binder + 10% of thermoplastic materials. Core and cavity material requirements is higher, especially the hardness. Quenching hardness 60-60 HRC, eventually die life of more than 1 million times.
Injection molding defects control problem can be divided into two aspects, one is the molding temperature, pressure, time, relationship function set; On the other hand is populating the feed flow in the cavity. So the mold design is particularly important.