How does a die casting machine work? The working principle of the die casting machine

Different from traditional casting:

1.Die casting process.

After pouring, the molten metal enters the pressure chamber before entering the mold, and then injected into the mold under pressure. This makes the filling speed of die casting faster than that of ordinary gravity casting.

2.In the die-casting process, there is a pressurization and pressure holding process, through the application of pressure, so that the metal after solidification of the internal density is better than the traditional casting.

The die-casting machine consists of the following parts.

1) Mold clamping mechanism.

Drive the die-casting mold to close and open. When the mold is closed, it has enough capacity to lock the mold to ensure that the parting surface of the mold will not expand during the injection filling process. The force of the clamping mold is called the clamping force (also known as the closing force), and the unit is 1,000 N.

kn), which is the primary parameter to characterize the size of the die casting machine.

2) Injection mechanism.

The molten metal in the pressure chamber is pushed at a specified speed, and there is enough energy to make it flow through the sprue and inner gate in the mold, and then fill into the mold cavity, and then maintain a certain pressure to transfer to the molten metal that is solidifying until the die casting is formed. After the injection action is completed, the injection punch returns to reset.

3) Hydraulic system.

Provide enough power and energy for the operation of the die casting machine.

4) Electrical control system.

Control the execution of each mechanism of the die-casting machine to run according to the predetermined program.

In this process, the main details such as the design of the die-casting mold and the selection of the parting surface, as well as the design of the sprue sleeve. Die-casting machine and die-casting mold must be maintained after a long time of operation, otherwise it is easy to fail, and it is necessary for the die-casting company to record the maintenance time and maintenance details in detail, do a good job in the statistics of information and materials, find problems in time, and improve work efficiency. Zhenli machinery.

Pro, the die-casting machine can be started but there is no pressure mainly due to three reasons for Qizhou Hexia: First, there is oil leakage in the injection part, which causes automatic pressure relief after the die-casting machine is started. 1.

Causes of oil leakage of parts: parts are not installed in place or wear and tear caused by long-term use of parts. 2.

Maintenance method: update the parts, the main part is the aging of the oil pump, or the wax proportional valve, the proportion plate is damaged or improperly adjusted, if you can not accurately judge which is the damaged part, you can use the replacement method, one by one to replace the part, this is also the most stupid method. Second, the second is the presence of nitrogen in the nitrogen cylinder, resulting in oil channeling in the cylinder.

3. The last point is the possible reasons for the automatic pressure relief of die castings due to insufficient total pressure or too slow pressure boost of the die-casting machine system: 1The pump has internal leakage, and its own displacement is smaller2

There is an internal leakage in the hydraulic system, and the hydraulic oil discharged by the pump does not reach the actuator, so it runs back to the oil tank.

The working principle of the die casting machine is as follows:

1. When the first-stage slow injection movement starts to be shot, the system excites the hydraulic oil to enter the cavity through the oil circuit integrated plate, and then enters the cavity through the channel, so as to promote the injection piston to move to the left and realize the slow injection.

2. The two-stage rapid injection movement, when the injection punch exceeds the pouring port of the barrel, the accumulator control valve is opened, and the hydraulic oil enters the cavity quickly through the mouth and mouth, and the amount of hydraulic oil in the cavity increases rapidly, and the injection speed increases.

3. The three-stage pressurized movement molten metal is filled into the cavity, when it is about to be terminated, the molten alloy begins to solidify, and then the forward resistance of the punch increases, which is controlled by the computer program, and the accumulator control valve is used to open, and it enters the cavity quickly, so as to promote the booster piston and the piston rod to move to the left.

When the piston rod and the inner and outer cone of the floating piston are engaged, they are truncated to form a closed cavity, and the pressure of the pressurized piston, the piston rod, the floating piston and the pressure of the cavity jointly make the piston obtain a pressurization effect.

4. The fast and slow time policy of slow speed, fast and pressurization can be adjusted by the control oil valve of the lead shouting oil circuit board: the power is transmitted through various hydraulic components (power components, liquid field actuators, control components, auxiliary components, working medium) and circuits, so as to achieve various actions.

Introduction to Die Casting Machine

A die casting machine is a machine used for pressure casting. There are two types: hot press chamber and cold press chamber. Later, they are divided into two types: straight and horizontal.

The die-casting machine hydraulically injects the molten metal into the mold under pressure to cool and form, and after the mold is opened, a solid metal casting can be obtained, which was originally used for die-casting leads.

1) Closing the mold;

2) pouring molten metal into the chamber by manual or other means;

3) The upper punch moves down at a low injection speed, and is quietly buried in the pressure chamber until it has just come into contact with the molten metal level;

4) The upper punch is pressed down with a higher injection velocity, while the lower punch and the upper punch maintain a relative distance of molten metal in the middle and move down synchronously;

5) When the lower punch moves down to the nozzle orifice, it just goes down to the bottom and is supported; Thus, the upper and lower punches together extrude the molten metal together and spray to the nozzle hole (a part of the sprue 6) at high speed;

6) molten metal passes through a sprue 6 that is made up of a nozzle, a gate sleeve 4, a cone hole of fixed die and a diverter 2, and is filled into the mold cavity from the inner gate 3;

7) the filling is completed, but the upper punch still maintains a certain pressure until the molten metal in the cavity is completely solidified into a die-casting 1; The molten metal in the sprue and the pressing chamber is solidified into a straight gate and a residual material cake 9 respectively;

8) Upper punch lifts and resets; At the same time, the lower punch moves upwards to cut the remaining material cake that is still connected with the straight gate;

9) The lower punch continues to rise, lift the remaining material cake out of the top surface of the pressure chamber, and then take it away manually or by other means;

10) The lower punch is moved down to reset to block the nozzle orifice;

11) Open the mold, the die-casting and the straight gate are left on the moving mold together, and then the die-casting is ejected and taken out; Once the remaining material cake is cut, the mold opening action can be executed immediately, or it can be slightly slowed down to the appropriate time, and has nothing to do with the action of lifting and resetting the lower punch;

At this point, a die-casting cycle is completed.

The press chamber of a hot chamber die casting machine is usually submerged in the molten metal of the crucible. In the die-casting process, the molten metal enters the chamber through the inlet when the injection punch rises: when the injection punch is pressed down, the molten metal fills the die-casting model cavity through the nozzle along the channel, and after the molten metal is cooled and solidified, the injection punch rises, and Qi Jian Zheng opens the mold at this time to take out the casting to complete a die-casting cycle.

1) Closing the mold;

2) pouring molten metal into the chamber by manual or other means;

3) The upper punch moves down at a lower injection speed, enters the pressure chamber and is just in contact with the molten metal level;

4) The upper punch is pressed down with a higher injection velocity, while the lower punch and the upper punch maintain a relative distance of molten metal in the middle and move down synchronously;

5) When the lower punch moves down to the nozzle orifice, it just goes down to the bottom and is supported; Thus, the upper and lower punches together extrude the molten metal together and spray to the nozzle hole (a part of the sprue 6) at high speed;

6) the molten metal passes through the sprue 6 which is made up of a nozzle, a gate sleeve 4, a cone hole of fixed die and a diverter 2, and fills into the mold cavity from the inner gate 3;

7) the filling is completed, but the upper punch still maintains a certain pressure until the molten metal in the cavity is completely solidified into a die-casting 1; The molten metal in the sprue and the pressing chamber is solidified into a straight gate and a residual material cake 9 respectively;

8) Upper punch lifts and resets; At the same time, the lower punch moves upwards to cut the remaining material cake that is still connected with the straight gate;

9) The lower punch continues to rise, lift the remaining material cake out of the top surface of the pressure chamber, and then take it away manually or by other means;

10) The lower punch is moved down to reset to block the nozzle orifice;

11) Open the mold, the die-casting and the straight gate are left on the moving mold together, and then the die-casting is ejected and taken out; Once the remaining material cake is cut, the mold opening action can be executed immediately, or it can be slightly slowed down to the appropriate time, and has nothing to do with the action of lifting and resetting the lower punch;

At this point, a die-casting cycle is completed.

1 Before starting the motor, first put the handle of the pressure relief valve on the vent.

Zhi pressure position, after the motor is running normally, release the pressure relief valve handle again.

Right 2 Before injection, the model must be heated to the specified temperature before it can be pressed into the metal solution. 3. Protective baffles should be used at the contact between the parting surface and the gate of the mold, and the operator must wear protective glasses.

The operator must not stand on the opposite side of the parting surface contact. In case the liquid metal splashes and injures people. 4 It is forbidden to bring open flame items close to the fuel tank.

When the temperature of the fuel tank exceeds the specified temperature of the equipment operation, water cooling should be applied. 5 Tools should be used when removing the casting and gate riser from the die casting mold. After removing the casting, the metal debris adhered to the mould and the vent should be removed in time.

6. When the work is completed, the oil pump must be stopped and all valves must be closed. If the holding furnace is used to keep the molten metal warm, the power should be turned off and the ventilation equipment on the holding furnace should be stopped.

The hot chamber die casting machine is mainly composed of clamping molds.

DU (also known as clamping device), ZHI injection device, hydraulic.

The DAO transmission system and the electrical version control system are composed of four parts, and the hot chamber die-casting mechanism is formed in Figure 1-1.

The mold clamping device mainly plays the role of realizing the action of closing and opening the mold, locking the mold and ejecting the product. It is mainly composed of shaped seat plate, dynamic seat plate, tie rod, clamping hydraulic cylinder, ejection mechanism, mold adjusting device, safety door, etc.

The injection device is a device that injects molten alloy into the cavity of the mold. It is mainly composed of pressure chamber, hammer, injection hydraulic cylinder, nozzle and other components.

The hydraulic transmission system is a system that transmits power through various hydraulic components and circuits, so as to realize various action procedures, which is mainly composed of hydraulic pumps, locking mold hydraulic cylinders, thimble hydraulic cylinders, buckle nozzle hydraulic cylinders, injection hydraulic cylinders, various control valves, accumulators, oil tanks, coolers, hydraulic oil, etc.

The electrical control system is to ensure that the machine works according to the predetermined pressure, speed, temperature and time, which is mainly composed of electric motors and various electrical components, instruments and electrical circuits.

1. Filling principle of hot chamber die-casting machine.

When the injection hammer head rises, the molten metal in the crucible enters the pressure chamber of the kettle through the inlet of the kettle, after clamping, when the hammer head is pressed down, the molten metal is filled from the nozzle head to the die-casting model cavity along the channel to solidify and form, the injection hammer head is lifted, and the casting is taken out by opening the mold to complete a die-casting cycle.

Figure 1-2