Stock code:SZ 002334
Current location:Home Solutions Machine Tools
Machine Tools
Application of MH500 Hydraulic Servo in Die Casting Machine
Click amount:
Abstract: MH500 is a special servo system with hydraulic control. The liquid pressure and flow specific process parameters are integrated into the driver control software. The unique PQ decoupling control scheme and multi-stage PID control technology make the molding faster and more precise, and it has been widely used in injection molding Machine, die-casting machine, hydraulic press, grinder and other hydraulic control equipment, in addition it can also improve single-class energy production and product accuracy.

Key words: die casting machine, pressure, flow double closed loop, constant power control technology

1. Introduction of die casting machine
The process of die-casting machine is generally divided into several stages, such as mold clamping, injection, pumping, core pulling, punching, thimble, cooling, accumulating and so on. In each stage, the hydraulic oil is pumped by pump motor to each oil cylinder to drive the transmission mechanism to complete a series of actions, and different pressures and flows are required at all stages.
As for the hydraulic system, the matching of pressure and flow is different in each stage, and the pump power is configured based on the maximum load in operation, and The load of die-casting machine is relatively large only in the high-voltage clamping and injection work phase in a working cycle, the other working stages are generally smaller, the load in the cooling process is almost zero. 
As for the pump motor, the die-casting process is out of varying load conditions. In the hydraulic system of dosing pump, the pump motor provides a constant flow at a constant speed, and the pressure and flow required for operation are determined by the pressure proportional valve and flow proportional valve, adjusting the opening of pressure or flow proportional valve to adjust the pressure or flow. The excess hydraulic oil flows through the overflow valve, which is called high pressure cutoff, where the energy loss is generally around 50%. 

2. Introduction of Hydraulic Servo

As the mainstream market of hydraulic servo suppliers, INVT industrial technology (original Shanghai Kinway Technologies, INC.) has more than 8 years development and marketing experience. Kinway brand MH500 hydraulic servo is widely used in the injection molding machine, die-casting machine, hydraulic press, grinder and other equipment with tens of thousands of market ownership.

As the dedicated servo system for hydraulic control, MH500 is the hydraulic servo that can achieve high-precision closed-loop control of pressure / flow with 3 times overload capacity, better flow response and pressure response performance; Build-in CAN bus function can meet the application requirements of large equipment multi-pump parallel; Unique PQ (pressure and flow ) decoupling control and PID control technology contribute to the faster and more precise molding; Standalone power range is 7.5kW-55kW, as for the die-casting machine with more than 320L/min system displacement, you can control scheme of multi – pump confluence due to the restriction of pump displacement and response speed. 

3. Characteristics of the hydraulic servo control plan 
1) The oil supply of energy saving: the system pressure, flow double closed loop, hydraulic system are in accordance with the actual needs of the flow and pressure, which has overcome the high energy consumption generated by high pressure overflow of ordinary quantitative pump system, and reduced the motor speed in the pressure maintaining, cooling and other low-flow working period, pump motor power consumption has been reduced by 50% -80%.

2) fast response, high production efficiency: fast response speed, pressure and flow rise time up to milliseconds, which have improved the response speed of hydraulic system and reduced the action conversion time, speed up the running beat of whole machine; when the die-casting machine hydraulic system automatically runs, the system pressure will instantly fall when the valve is open, MH500 servo can be quickly to add fuel within 30ms and restore the pressure to set value. 
3) Stable and precise pressure : strong servo - control ability, the close loop pressure control mode makes the system pressure very stable, pressure fluctuation is less than 1kg, which has improved the quality of metal products; The arbitrary pressure and flow curve running set by the computer have created conditions for the development of new forming technology of metal products.
4) Low noise, weak vibration: Because the server is started under vector control, the servo motor runs very smoothly, and the noise of motor  can’t be heard under normal conditions, there is only very little vibration sense in operation, that is the so-called moistening things silently. 
5) Improve rotational speed and large flow: the constant power control technology improves the rated speed 1500RPM of motor to constant power speed 2000RPM, which has enhanced the clamping speed of die casting machine; When ensuring the equal flow rate, choose a small - displacement pump, motor and drive with small - level power, thereby reducing the system cost.
4. Characteristics of servo die casting machine
1) High single - mode energy - saving rate: completely eliminate the high pressure throttle, 40%-70% energy - saving than traditional die-casting machine.
2) High response speed of servo system: 0-100% pressure change as fast as 30ms, improving 5%-12% production efficiency. Take Yizumi DM500 as example, as for the production of a product, the original cycle is 34s, the cycle time is improved to 31s after adopting servo system.
3) Reducing hydraulic oil temperature: reduce the amount of cooling water for more than 30%, water cooling is even not needed in certain circumstances, improving the service life of hydraulic components and reduce the amount of maintenance. 
4) Improve the working environment: reduce running noise, in non-working condition, the servo motor is stopped, without noise, generally running at full load is a short time, which has reduced the overall noise level.
5. The application of transformed die casting machine
In the composition of the cost of die-casting machine production, electricity accounted for a considerable proportion, and the power consumption of traditional die-casting machine pump motor accounted for a 50% -80% proportion of the entire equipment.
The energy saving transformation of die-casting machine has greatly reduced the energy consumption of oil pump motor and realized the high energy-saving rate of die-casting machine. At the same time, it has great effect on the improvement of machine precision, production efficiency and qualified rate,
Ordinary die-casting machine servo transformation will become the leading direction of domestic die-casting machine energy-saving transformation, only in the first half year, INVT has transformed more than 200 units die-casting machines in East China area.
    After the energy saving transformation of die-casting machine servo, the oil supply of the system pressure, flow double closed loop and hydraulic system will be in accordance with the actual needs of flow and pressure, which has overcome the high energy consumption generated by the high pressure overflow of ordinary quantitative pump system. After the energy saving transformation of die-casting machine, when the servo system controls the oil pump, because the servo can quickly respond to the given control signal, and flexibly switch between speed control and torque control to achieve the motion control or die control, so the working cycle can also be shortened, and the quality of die-casting products have also increased; Reasonable fuel supply control has reduced the load and power loss of cooling system.


Figure 1: motor and oil pump before the transformation of die-casting machine 

Figure 2: motor and gear pump after the transformation of die-casting machine servo 

Figure 3: the transformation application of MH500 hydraulic servo in Yizumi die-casting machine

Figure 4: the transformation application of MH500 hydraulic servo in the force casting machine

Figure 5: the transformation application of MH500 hydraulic servo with double pump 

Conclusion:
In recent years, with the customers’ high demand for the efficiency, stability, low energy consumption, maintainability and other aspects of die-casting machine, and the maturity application of servo motor and the substantial decline of price, the drive part of die-casting machine also evolved from the application technology of quantitative pump into a servo technology. 
MH500 servo energy saving technology is another important breakthrough of hydraulic drive technology in the field of die casting machine. Under the premise of combining the cost, performance and stability, MH500 electric hydraulic servo system has perfectly solved the cost, efficiency, oil temperature and other issues concerned by customers, which has represented the development direction of die casting machine.





Related products recommended
Email: overseas@invt.com.cn
Learn more about latest solutions and cases, please enter your email address to subscribe to
Online top