Title: Why Should Your Company Make The Move To AllElectric Injection Molding
1Why Should Your Company Make The Move To
All-Electric Injection Molding ?
- Niigata Engineering
- Mark Zulas
- Applications Engineer
2How is an All-Electric Injection Molding Machine
Different From a Standard Hydraulic Injection
Molding Machine?
3All-Electric System Vs. HydraulicHydraulic
Machine Control System
Motor
Coupling
Pump
Tank
Filter
Hose
Valve
Cylinder
Hose
Valve
Hose
Hose
Heat Exc.
Hose
Tank
4All-Electric Control System
Motor
BallScrew
Pulley
Belt
Pulley
5How Do Electric Machines Make Linear Motions?
- The Servo Motor Rotates The Ball Screw Via The
Timing Belt. - The Ball Nut Follows The Threads Of The Ball
Screw In A Linear Motion As Screw Turns.
6What Is A Ball Screw And Ball Nut?
- Converts Rotary Motion To Linear Motion.
- Ultra Low Friction.
- Normal Efficiency Of Over 90.
- Nut Allows Ball Bearings Full Movement Within The
Nut.
7Timing Belt
- Teeth On The Belt Eliminate Slippage.
- Belt Helps To Absorb Shocks To Motor From
Mechanical Collisions. - Belt Constructed With State Of The Art Materials
For Long Life.
8What Is An AC Synchronous Servo Motor?
- Designed for compact size.
- Extremely efficient cooling for heavy loads.
- Designed to with stand loads of up to 300 rated
capacity.
9AC Synchronous Servo Motor And Amplifier
- Speed controlled by changing the frequency.
- Amplifiers equipped with 80MHz. RISC computer.
- Amplifier Monitors Motor Current, Speed, And
Temperature.
10How Are Positions Monitored?
- The Encoder Is Connected To The Motor Shaft.
- Each Motor Revolution Has Up To 16,384 Pulses Of
Information To Use For Position. - Encoder Signal Is Wired To The Servo Amplifier.
Encoder Mounted To The Rear Of The Servo Motor
11Encoder Accuracy And Control
12Machine Response Time And CPU Scan Time
- Typical Hydraulic CPU Scan Time 20ms
- Typical Hydraulics Response Time 50ms
- All-Electric Servo Scan Time 0.2ms
- All-Electric IMM Response Time 1ms
- Allows Injection Time Control To 0.001sec.
13How Accurate And Repeatable Is The Positional
Control?
- Ejector Stroke 0.001 in.
- Clamp Position 0.001 in.
- Screw Position 0.0005 in.
-
- Positional Set Points Will NOT Overshoot.
- Low Pressure Mold Protect Can Be Set To Protect
Against Very Small Parts. - Easier To Set Machine Up For Automation.
14What Units Are Used For Setting The Machine
Profiles?
- Speed Settings Inches/Sec. or mm/Sec.
- Pressures Plastic PSI or Plastic Kgf/cm.
- Positions Inches or mm.
- True Engineering Units - Not
- Moving Molds Between Like Machines Does Not
Require A Different Process
15How Is Clamp Tonnage Obtained?
- Clamp Mechanism Must Be Of The Toggle Design.
- Motor And Ball Screw Drive Toggle Linkage.
- Toggle Is A Mechanical Lock Over.
- Tonnage Is A Function Of Tie Bar Stretch
16How Are Large Clamps and Injection Screws Moved?
Dual Servo Drives and Ball Screws Share The Load
17Combining Linear Bearings And Ball Screw
Technology
- Extremely Low Friction
- Dual Ball Screw Design Eliminates Side Loading
- Low Maintenance
18How Is Injection Pressure Measured?
- Injection Pressure Monitored By Load Cell Mounted
behind Injection Screw. - Load Cell Is Compressed Between Screw And Servo
During Injection. - Load Cell Signal Sent To Motor Amplifier.
- Ejector And Clamp Pressures Monitored By Motor
Load.
Screw
Motor
19Stable Performance At Low Speed And Pressure
- No Hunting Of Drive Motion Like D.C. Drive Or
Hydraulic Would Exhibit. - Slow Charging Speeds Ideal For Shear Sensitive
Materials.
20Why All-Electric Machines Use Less Power
- Electric Method
- Electric Machines Use Small Motors To Move Each
Function Of The Machine. - The Servo Motors Use Energy Only When They Are
Running. - The Servo Motors are Off During Dwell Times Such
As Part Cooling Time.
- Hydraulic Method
- Large Induction Motor Needed to Drive Pump.
- The Motor Always Has Some Load Put On It Due To
Pump. - Large Amounts Of Power Required To Drive Pump Up
To High Pressure For Inject Or Increased Volume
For Charging.
2185 Ton Energy Comparison And Savings
22Savings Increase With The Machine Size
Annual Savings 8,200.00
- Cycle Time 56 Sec.
- Shot Mass 498 Grams
- Material PC
- Part Automotive Lamp Housing
- Total Savings 17.2 kW/H
- Based On Energy Cost of 0.08 per kW/H.
23Effects On Energy Savings
- The Larger The Part Weight, The Greater The
Savings. - The Longer The Injection Fill And Hold Times, The
Greater The Savings. - The Longer The Time Between Shot Size Made And
Cooling Time Complete, The Greater The Savings. - Multiple Clamp Speeds Or Numerous Ejector Strokes
Equal Greater Savings.
24Lower Water Requirements
- No Water Required To Cool Hydraulic System.
- The Only Water Is Used To Cool The Feed Throat
- Flow Of Water Is Controlled By Manual Flow
Control And By The Temperature Set On The Heater
Control Screen
Feed Throat Flow Control
25Advantages To Using Less Water
- Less Water Used Will Result In Less Water Being
Evaporated From Closed Loop System Less Make Up
Water Lower Water Bill. - Will Not Have To Increase Water Cooling System
Due To Adding Machines. - Can Replace One Hydraulic Machine With Four Or
Five All-Electric Machines And Not Effect The
Cooling System Load.
26No Oil Less Work
- No Oil Leaks
- No Floor Dry
- Less Housekeeping
- Eliminates Oil Drum Storage
- No Fire Code Regulations Due To Combustible
Material - No Oil Filters Or Magnets
- Only One Control System To Troubleshoot
- Less Heat Generated
27Better Working Environment
- Air Conditioning Costs Associated With IMM Are
Cut In Half - Machine Noise Levels Of Less Than 65 Db.
- Vibration Levels Associated To IMM Cut In Half
28Time For Pay Back Of Difference In Initial Cost
Average Time Required Is Two To Three Years
29Excellent Control To Speed And Pressure Profiles
- Quick Response To Changes In Injection Speed And
Hold Pressure Bring Consistency To Part Quality
30All-Electric Machines Can Control Rate Of
Acceleration
- Ability To Adjust The Rate Of Acceleration For
Injection Speed Allows To Correct For Visual
Molding Defects
31All-Electric Machines Offer Ramped Acceleration
- Servo Drives Allow For Linear Control Of
Injection Fill Speeds And Hold Pressures
32Fill Time Variation (Std. Dev. - 1 Sigma)PPR
Magazine
- Repeatability of Injection Profile and Positional
Transfer 0.0005 Seconds Deviation In Fill Time
33Part Weight Variation (COV)In Grams - Machines
In The 150 Ton Range
- Coefficient of Variation STD/AVG100
- Closest Hydraulic Is 25 Greater Than Electric
34How Can Material Be Saved By Using An Electric
Machine?
Machine Accuracy And Repeatability Material
Savings
Normal Part Weight Variation
35Precise Injection Velocity ControlPPR Magazine -
Machines In The 85 Ton Range
36Constant Pressure FillingWith Adaptive Flow
37All-Electric Machines Give Simultaneous Multiple
Functions
- Eject During Clamp Opening - Eject On The Fly
- Ejector Degating
- Screw Rotate During Clamp Opening Motion
38Compact Design Equals Smaller Machine Footprint
- Latest All Electric Design 23 Shorter Than The
Same Size Hydraulic Machine. - More Floor Space For Auxiliary Equipment
- More Room For Secondary Operations
39Preventative Maintenance
- Grease Clamp Toggle And Tie-Bar Bushings
- Record Heater Band Amperage Usage
- Calibrate Injection Load-Cell
- Visual Inspection For Damage Or Wear
- Check Timing Belts For Tension And Wear
40Maintenance Costs
- Typical Parts Needed To Have In Stock
- Heater Bands
- Thermocouples
- Grease
Typical Maintenance Costs Including Preventative
Maintenance Are Less Than 1,000.00 PER YEAR!
41What Should You Look For From A Supplier?
- Electric Machines Toggle Clamp - History
Building Toggle Machines - History of Producing All-Electric Injection
Molding Machines - History of Producing Servo Motors And Amplifiers
- History Using Servo Controls In Other Fields (CNC
Machine Tools)
42How to Calculate SavingsSample Comparison
- Machine Power Consumption
- 1982 Engel 275 Ton Hydraulic 36.0kW/h
- 2002 Niigata 310 Ton All Electric 4.8kW/h
- Hydraulic 6000 hours X 0.08kW X 36.0kW/h
17,280.00 - Electric 6000 hours X 0.08kW X 4.8kW/h
2,304.00 - Annual Savings 14,976.00
- Heat Exchanger Power Consumption
- Cooling Load 50HP X 0.1 Ton 5 Tons of Cooling
- Cooling Power 5 Tons X 0.211 kW/Ton 1.055Kw
- Energy Cost 1.055Kw X 0.08Kw/h X 6000 Hours
506.40 - Estimated Cost of Make up Water 200.00 / Year
- Cooling Cost For Electric Machine 0.00
- Annual Savings 706.40
43Savings CalculationsContinued
- Annual Material Savings
- 6000 Hrs./Yr. X 1 Material Savings X 2.45 / X
13.2 /Hr. 1,940.40 - Annual Savings due to Productivity Gains
- 6000 Hrs./Yr X 3 Increase in Production X 60.00
Machine Rate 12,000.00 - Annual Maintenance Savings
- Cost for Hydraulic Machine Preventative
Maintenance 4,720.00 - Cost for Electric Machine Preventative
Maintenance 910.00 - Savings 3,810.00
- Housekeeping Costs
- Hydraulic Oil Clean Up 15 Minutes / Day _at_ 250
Days / Year - 20.00 Hour Labor Cost X 625 Hours / Year
1,250.00
44Why Should Your Company Buy An All-Electric IMM?
- 34,682.40 Year Savings!
- Energy Savings
- Productivity Increased
- Increased Quality
- Material Savings
- Ease Of Use
45Who Should You Contact For More Information?
Niigata PMD DJK-Global 245 Spring Lake
Dr. Itasca, IL Phone 800-843-1672