Whether it is a plunger injection machine or a screw type injection machine, the system is composed of four subsystems: injection, mold clamping, transmission and control. The following figure is an injection molding machine structure.

 

 

1, Injection System

Including the screw or plunger and cylinder feeding, heating device, nozzle, spreader (plunger injection machine) etc...

 

Take the screw injection machine as an example:

 

(1) Screw

In the powder extrusion process, the extruder also uses the screw device, but the injection machine screw and the extrusion screw are different:

 

A, The injection machine has both rotational and axial movement, while the extruder screw only rotates;

 

B, The ratio of the length to diameter and the compression ratio of the injection machine screw are smaller than the extruder screw;

 

Note: compression ratio: the ratio of the volume of the screw at the feed port to the volume of the last slot in the forming section.

 

(2) Barrel

Basically the same as the extruder barrel 

 

(3) Nozzle

The function of the nozzle is to increase the flow velocity of the melt so that it can fill the mold quickly. It can be divided into two types: open nozzle and closed nozzle. The former is simple in structure and small in pressure loss, but cannot prevent tape casting. Meanwhile, the latter is easy to use and can prevent casting, but the structure is complex and the pressure loss is great.

 

2, Clamping System

With enough clamping force, the clamping system plays the role of switch mold. It is composed of a fixed plate, a moving plate, a die cylinder and an ejection device. Among them, the ejector is used for demoulding of products. There are two kinds of hydraulic and mechanical.

 

3, Transimission Gear

The transmission mechanism of the injection machine mainly consists of motor, gear, cylinder and oil etc... The hydraulic circuit provides the drive for all action. It provides drive for movement throughout the hydraulic circuit.

 

4, Control System

It mainly consists of motor, switch and relay. It plays the role of motion control.

 

Powder injection molding materials is actually a high filling thermoplastics, the basic principle of which is the same as that of thermoplastic injection molding. Usually, the barrel temperature, mold temperature and injection pressure are higher in injection molding. 

Mixing is the process of adequately mixing the raw powder and binder at a certain device and temperature to make them homogenized and meet the requirements of the injection. The nature of the feed determines the performance of the final injection into the product, so this process of mixing becomes very important, which involves factors and methods of adding binder and powder, mixing temperature, mixing device characteristics and many other factors. 

There are many kinds of darts, such as wood, alloy and nylon, etc. Most professional players are using tungsten alloy darts. So what are the advantages of tungsten alloy darts?