Injection Molding Machine Frequency Inverter

Top manufacturer of AC drive in China!Creative Technology, Service leading!

Best Manufacturer of AC Drive, Servo Drive, PLC, HMI, Solar Pump Inverter…

Energy Saving Solution for Injection Molding Machine with SF81 and SD610/620

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1.What is the benefit in injection molding retrofitting with VFD. Injection Molding is a common method of plastic processing in which thermoplastic materials can be molded into arbitrary complex shapes ,Most injection molding machines use complicated hydraulic systems to perform the necessary work of the process. Hydraulic system flow and pressure requirements vary throughout the cycle and in many cases ,excess fluid that is not required by the process is throttled back to the reservoir ,wasting motor energy and producing additional thermal load on the cooling system .variable speed drives can be used to allow injection molding machine hydraulic systems to vary the amount of fluid that is throttled ,reducing the amount of wasted energy.

Traditional displacement pump control system

With variable speed driveFor energy saving

Speed regulating

forFlow and pressure control


Figure 1 : Required hydraulic Fluid Flow Rate Through one cycle Figure 2 : Required pressure Through one cycle

There are some basic rules of thumb concerning VSD and IMMs that are typically applied .Most VSD installer expect energy saving of 20-50% of pre-retrofit motor energy use for machines with constant displacement pumps. Machines with variable displacement pumps will have lower savings ,and only a few VSD distributors consider machines with variable displacement pumps appropriated for VSD retrofits .However ,it is generally felt that potential energy saving is more strongly depend on cycle time breakdown ,especially percentage idle time in the cycle ,than on machine parameters or other process parameters .


SF81 System provides precise pressure and flow controls for each injection molding process and solves the energy waste issues of traditional injection molding machine. This solution helps to improve product quality, market competitiveness and productivity. SF81 injection molding machine servo drive regulates the speed of motor and oil pumps according to the required pressure and flow signal in difference working process. The servo system collects real time pressure of pipe by pressure sensor and then do signal comparison calculating with signal came from upper controller, to achieve pressure and speed dual close loop control, automation adjust the speed of motor no need discharge excess oil by throttle control to tank. The energy saving up to 20% to 60%

Veichi SF81 Injection Molding Machine Servo Drive for asynchronous motor

SF81 IMM special synchronous servo drive easy to install, no need pressure sensor, encoder, no need to replace the hydraulic pump and motor exited . It is a cost-high performance AC drive that very suitable for hydraulic pump machine: http://www.veichi.org/product/electric-drive/sf81-asynchronous-servo-control-vfd-for-injection-molding-machine.html

http://www.veichi.org/product/electric-drive.html

http://www.veichi.org/product/electric-drive/sf81-asynchronous-servo-control-vfd-for-injection-molding-machine.html

http://www.veichi.org/product/electric-drive/sf81-asynchronous-servo-control-vfd-for-injection-molding-machine.html


The advantage feature of SF81 asynchronous servo drive1. Quick respond speed, high efficiency The response speed of pressure from 0 to maximum is 0.1s is available with SF81 servo drive control. The response speed proved much fast compare to traditional hydraulic pressure control system with overflow valve only help to improve the production efficiency and shorten the work cycle.

2. Highly Repetitive accuracy of IMM systemThe repetitive accuracy can be improved to 3%, higheraccuracy than traditional control method after retrofittingby SF81 servo drive, which help to ensure the stability of product and reduce the defective percentage.

3. Energy saving up to 25% to 70%.Achieving 25% to 70% energy saving , that depends on is the speed value of mould technique parameters. The more energy saving ratio , the smaller speed value ( 0 to 99%). 70% of energy saving is possible if the speed value during to 0 to 30%, also can get 25% energy saving if the speed value over 90%, with little cooling time as well.

4. Lower running noise.Running noise reduce remarkable, more quiet running In low speed, less than 70 DB in good condition.

5. Strong overload capacity Overload capacity: 150% rated current for 120s, 180%

rated current for 10s, 250% rated current for 1s.

6. Lower oil temperature The flow and pressure are controlled by SF81 servo drive to avoid redundant heat generated, which reduce the oil temperature, even no need refrigeration and saving a lot of cooling water or oil.

7. Easy to maintain It has built backup power supply circuit, which will not effect injection machine working when SF81 synchronous servo drive are repairing.

8. Designed to special function for IMM energy saving, has built special control channel.Special programmable parameters suitable for IMM, easy to set.

Top manufacturer of AC drive in China!Creative Technology, Service leading! 9. Powerful faulty restart function, No stop running with slight alarm occur, don’t effect injection cycle.

10. Multiple channel input signal terminal, built in 0-1A to 0-10V signal conversion card 0 to 1A/0-5A,0-10V/ 0-5V, 4-20mA/0-20A multiple input analogy signal is available.

11. Outstanding performance Excellent soft start ability, 0.1s of accel/ decel time that to meet IMM operation condition very wellLarge torque output, 180% rated torque output even under 0.3Hz.

12. Easy to configure the curve of frequency -analog signal.Adjusting this curve according the characteristic of hydraulic to meet requirement.

Built back up utility grid circuit

Independent air duct and water proof design

Top manufacturer of AC drive in China!Creative Technology, Service leading! The operation principle of SF81 synchronous servo driveVeichi SF81 synchronous servo drive apply multiple channel signal input control, proportional pressure and flow signal for main stream control as for main source, attached several signal as for auxiliary source to adjust flow and pressure signal given when there pressure and flow is not enough during injection cycle.

It is very easy to superposition multiple voltage or multiple segment frequency to make flow or pressure bigger when the pressure requirement in specify injection cycle ( close, plastic melting and injection ) is not enough, which will not effect the working condition.The wasted energy of motor is minimum during whole variable load. It can make motor run in stability and accurately to achieve high energy saving and improve the product quality.

Note: This diagram suits for the proportional valve with 0-1A asynchronous servo drive2. The digital signal of diagram showed is negative output, if the digital output ( mold open, mold lock, injecting, melting plastic ) is positive, the common point will be 0 V, not 24V. And the diode should be change the direction).


Proportional valve wiring schematic

To SF81 drive

Specification of SF81

Model Power(KW)Rated

current (A)

SF81-T3-7R5K 7.5 16

SF81-T3-011K 11 25

SF81-T3-015K 15 32

SF81-T3-018K 18 38

SF81-T3-022K 22 45

SF81-T3-030K 30 60

SF81-T3-037K 37 75

SF81-T3-045K 45 90

SF81-T3-055K 55 110

SF81-T3-075K 75 150


Veichi SD610/620 Electro Hydraulic Servo System

Energy Saving High Precision High Efficiency Noise Reduction Long Working

China No. 1 brand.

Top manufacturer of AC drive in China!Creative Technology, Service leading! The advantage of electro hydraulic system, please refer the catalog of electro hydraulic

Energy Saving.The electro employ pressure and flow double close loop control o hydraulic system supply the oil according to the actual demand with employing pressure and flow double close loop control mode. It will overcome the high energy consumption of high pressure leakage in general constant displace pump. It can achieve energy saving up to 30% to 80%.

PrecisionImproving the pressure stability with close loop pressure control mode. The pressure fluctuation less than ±0.3bar, high duplication accuracy.

High efficiency The system response speed up to 20ms, improve the explosive moments, increasing the productivity.

Lower noise The electro hydraulic system noise limit to 65dB, improve the operation environment.

Long service lifespanThe temperature rise of oil is 3 to 10 , working in 35 in door temperature no need cooling ℃ ℃ ℃water, reduce the water using sharply.Reduce the oil changing frequency, extend the service lifespan of oil quick wear parts.


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Comparison of retrofitting for IMM with VFD, synchronous PMSM motor, SF81 asynchronous servo drive: 1. Retrofitting with frequency inverter of IMM. a. Retrofitting with V/f frequency inverter can bring us energy saving but there are some problem happen. b. Not good control accuracy without feedback control, low efficiency, lower energy saving, sometime effect

product quality, product quality not stable.c. This is solution is very popular before 2010 even with vector control inverter, but now it was weed out

graduallyd. Veichi AC70 with running curve adjusting features can remedy short point of retrofitting with inverter.2. Retrofitting with asynchronous motore. High energy saving, higher efficiency and outstanding accuracy control with close loop feedbackf. Stable flow and pressure to make sure good quality of productg. Lower investment, no need replace the exits motor, short payback. 3. Retrofitting with SD610/620 Electro-Hydraulic Servo Drive with permanent magnet synchronous motor High energy saving, high efficiency and good accuracy control can be achieve with vector control servo drive and synchronous motor. But costly installation and retrofitting expense, long payback with synchronous motor replace

Solution general fixing pump

variable capacity pump

V/f frequency inverter

PMSM with servo drive motor

asynchronous sevo drive

Energy Saving NO A little 20% to 40% 25% to 75% 25% to 75%stability middle level Middle level Low High High Dynamic response Middle level Middle level Slow High High Noise Middle High Middle Low Low Oil temperature High Middle Middle Middle Low Maintenance cost Low High Middle High Low Investment cost Low Middle Middle High Middle


Energy saving effect budget of servo system retrofitting for constant replacement pumps. IMM clamping force, Motor power, before retrofitting power consumption, after retrofitting power consumption, Annual energy saving, Annual electrical charge saving

IMM mould clamping force

The power of motor

Energy consumption/hour(before

retrofitted with fixed pump)

Energy consumption/hour(after

retrofitted with SF81 drive)

Energy Saving per year KW.H/Y

Cost Saving( CNY)

T Kw.h Kw.h/h Kw.h/h Kw.h/Year CNY/Year58T 7.5 3.375 2.025 17739 14191.290T 11 4.95 2.97 26017 20813.6

120T 13 5.85 3.51 30748 24598.4160T 115 6.75 4.05 35478 28382.4200T 18.5 8.325 4.995 43756 35004.8250T 22 9.9 5.94 52034 41627.2300T 30 13.5 8.1 70956 56764.8360T 37 16.65 9.99 87512 70009.6450T 45 20.25 12.15 106434 85147.2530T 55 24.75 14.85 130086 104068.8

650T 60 27 16.2 141912 113529.6800T 74 33.3 19.98 175025 140020900T 82 36.9 22.14 193946 155156.8

1000T 90 40.5 24.3 212868 170294.4

1250T 110 49.5 29.7 260172 208137.6

1500T 120 54 32.4 283824 227059.2

Note:1. Before retrofitting, calculating with 45% load power consumption per hours 2. After retrofitting, calculating with average energy saving 60%, 70% IMMs after with retrofitting can achieve 60% energy saving. 3. Annual energy saving calculating with 24 hours, 365 days.4. Electrical charge is 0.8 CNY per hour, 1USD for 6.1CNY.5. The budget will be difference according to difference condition. above table only for reference.

Engineering

Injection Molding Machine Frequency Inverter