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IMSJ_Actuator
IMSJ_Actuator

Machine (Acme) Screw Jacks

Mechanical Actuators - 1/4 to 350 Ton

IMSJ_Actuator
IMSJ_Actuator
1/4 to 350 ton capacity. Machine (Acme) screw actuators offer positive mechanical action, precise positioning, and uniform lifting speeds. Standard configurations include upright or inverted units with translating or rotating lifting screws, and top plate, threaded, or clevis ends.
Duff-Norton offers a complete line of both standard and custom engineered machine screw actuators for applications up to 350 tons.

Features & Benefits

FEATURES & BENEFITS
Machine Screw Actuators 1/4 ton to 350 ton

Precise Positioning

Machine Screw Actuators can be controlled accurately for positioning within thousandths of one inch.

Self Locking

Models featuring higher gear ratios are inherently load holding as long as the actuator is not subject to vibration

Uniform Lifting Speeds

Since many actuators feature the same gear ratios different capacities can be used in the same application to lift unevenly distributed loads with uniform speeds.

Quick, Sure Operation

All actuators are designed and built to be positive acting, for accurate response to motive power.

Specifications

Performance Table Instructions 
When reviewing and Duff-Norton Actuator Performance Specification Table, as part of the process of selecting the best-suited actuator for your application, there are several important worm-gear ratios to consider.
Standard Ratio - is frequently chosen when higher speeds and efficiency ratings are desired.
Optional Ratio - is frequently chosen when the application requires higher lifting capacities, lower speeds, or to ease the use of a handwheel.
Numeric Ratio - is frequently chosen for applications requiring fine adjustments, higher lifting capacities, lower speeds, the easy use of a handwheel, self locking applications, and also offers the benefit of an even number of worm input turns per inch of stroke.

Specifications - Standard, Optional, and Numeric Ratios - Capacities 1/4 to 20 Tons
Capacity (Tons) 1/4 1/2 1 2 3 5 10 15 20
Max. Speed C-face Driven (in/min) 72.0 72.0 108.0 108.0 108.0 108.0
Max. Speed Reducer Driven (in/min) 14.4 21.9 21.9 21.9 21.9 21.9
Lifting Screw Diameter (in) 1/2 5/8 3/4 1 1 1-1/2 2 2-1/4 2-1/2
Pitch (Std. & Opt.) 0.250 0.125 0.200 0.250 0.375 0.375 0.500 0.500 0.500
Pitch (Numerical) 0.250 0.250 0.250 0.250
Type ACME ACME ACME ACME ACME ACME ACME ACME ACME
Worm Gear Ratios Standard 5:1 5:1 5:1 6:1 6:1 6:1 8:1 8:1 8:1
Optional No. 1 20:1 24:1 24:1 24:1 24:1 24:1 24:1
Optional No. 2 12:1 12:1 12:1
Numeric Ratio 20:1 25:1 25:1 25:1 25:1 25:1 25:1
Turns of Worm for 1 inch Stroke Standard 20 40 25 24 24 16 16 16 16
Optional No. 1 100 96 96 64 48 48 48
Optional No. 2 48 48 32
Numeric Ratio 100 100 100 100 100 100 100
Worm Torque at No
Load (in-lb)
Standard 2 2 5 5 5 10 20 20 30
Optional No. 1 5 5 5 10 20 20 30
Optional No. 2 5 5 10
Numeric Ratio 5 5 5 10 20 20 30
Maximum Horsepower
per Actuator
Standard 1/3 1/3 1/2 2 2 4 5 5 5
Optional No. 1 1/4 1/2 1/2 3/4 1-1/2 1-1/2 1-1/2
Optional No. 2 3/4 1-1/4 2
Numeric Ratio 1/4 1/2 1/2 3/4 1-1/2 1-1/2 1-1/2
Worm Torque at Full
Load* (in-lb)
Standard 13 21 55 120 165 450 750 1430 1811
Optional No. 1 25 50 75 185 400 820 1035
Optional No. 2 75 105 275
Numeric Ratio 25 48 72 175 370 640 925
Efficiency Rating (%) Standard 30.6 18.9 23.1 22.1 24.2 22.1 26.5 20.9 22.0
Optional No. 1 12.7 13.3 13.3 13.4 16.6 12.1 12.8
Optional No. 2 17.7 19.0 18.1
Numeric Ratio 12.7 13.3 13.2 9.1 8.6 7.5 6.9
Key Torque (in-lb) Std. & Opt. 1 & 2 40 70 175 460 670 1750 4077 6645 9369
Numeric Ratio 175 460 670 1599 4077 6645 9369
Maximum Worm Speed at Full Load (RPM) Standard 1616 1000 573 1051 766 560 420 220 174
Optional No. 1 630 630 631 278 236 115 91
Optional No. 2 630 751 458
Numeric Ratio 630 657 437 270 256 148 102
Maximum Load at Full Horsepower and 1750
RPM (lb)
Standard 455 527 520 2332 2521 3047 4386 3406 3370
Optional No. 1 400 1156 1888 1064 1791 1276 956
Optional No. 2 1258 2402 2339
Numeric Ratio 400 1210 1162 1031 1944 1646 1074
Weight with 6 inch Stroke (Raise) (lb) 2 2 5 17 17 35 52 66 93
Weight per Add.1 inch Stroke (Raise) (lb) 0.1 0.1 0.3 0.3 0.3 0.9 1.4 1.5 2.6
Note: All actuator units can be supplied with standard raises up to 24 inches. Special raises up to 20 feet are available upon request. Closed height dimensions may increase for actuators supplied with bellows boots.
Specifications - Standard, Optional, and Numeric Ratios - Capacities 25 to 250 Tons
Capacity (Tons) 25 30 35 50 75 100 150 250 300* 350*
Max. Speed C-face Driven (in/min) 107.0 107.5 107.0  
Max. Speed Reducer Driven (in/min) 22.2 22.2 22.4 12.2  
Lifting Screw Diameter (in) 3 3 3-3/4 4-1/2 5 6 7 9  
Pitch (Std. & Opt.) 0.666 0.666 0.666 0.666 0.666 0.750 1.000 1.000  
Pitch (Numerical) 0.320 0.320 0.320 0.320  
Type ACME ACME ACME Mod.
Sq.
Mod.
Sq.
Mod.
Sq.
Mod.
Sq.
Mod.
Sq.
 
Worm Gear Ratios Standard 10-
2/3:1
10-
2/3:1
10-
2/3:1
10-
2/3:1
10-
2/3:1
12:1 12:1 12:1  
Optional No. 1 32:1 32:1 32:1 32:1 32:1 36:1 36:1  
Optional No. 2  
Numeric Ratio 32:1 32:1 32:1 32:1  
Turns of Worm for 1 inch Stroke Standard 16 16 16 16 16 16 12 50  
Optional No. 1 48 48 48 48 48 48 48 36  
Optional No. 2  
Numeric Ratio 100 100 100 100  
Worm Torque at No
Load (in-lb)
Standard 40 40 50 100 150 200 250 200  
Optional No. 1 40 40 50 100 150 200 250  
Optional No. 2  
Numeric Ratio 40 40 50 100  
Maximum Horsepower
per Actuator
Standard 8 8 8 15 15 25 25 35  
Optional No. 1 2-1/2 2-1/2 2-1/2 6 6 11 11  
Optional No. 2  
Numeric Ratio 2-1/2 2-1/2 2-1/2 6  
Worm Torque at Full
Load* (in-lb)
Standard 2220 2640 4000 7500 12000 16000 28110 20000  
Optional No. 1 1401 1685 2400 4200 6601 8600 15500  
Optional No. 2  
Numeric Ratio 1500 1800 2411 4040  
Efficiency Rating (%) Standard 22.4 22.4 17.4 13.3 12.4 12.4 14.2 8.0  
Optional No. 1 11.8 11.8 9.7 7.9 7.5 7.7 8.6  
Optional No. 2  
Numeric Ratio 5.3 5.3 4.6 3.9  
Key Torque (in-lb) Std. & Opt. 1 & 2 14000 16800 26500 47110 73000 118200 216000 423300  
Numeric Ratio 11474 13770 18561 30970  
Maximum Worm Speed at Full Load (RPM) Standard 227 190 126 126 79 98 56 110  
Optional No. 1 112 94 66 90 57 81 45  
Optional No. 2  
Numeric Ratio 105 87 65 94  
Maximum Load at Full
Horsepower and 1750
RPM (lb)
Standard 5691 5691 4220 5949 4939 8865 7003 26780  
Optional No. 1 1839 1839 1193 2831 1537 4670 2875  
Optional No. 2  
Numeric Ratio 1714 1714 1187 2946  
Weight with 6 inch Stroke (Raise) (lb) 160 160 240 410 650 1200 1350 2700  
Weight per Add.1 inch Stroke (Raise) (lb) 2.5 2.5 3.7 5.5 6.5 9.0 12.6 23.0  

*Duff Norton has provided special actuators rated at 300 tons and 350 tons for certain applications. Actuators at these capacities are provided under specific Duff Norton / customer agreement as to the actuator’s performance parameters. Please contact our Application Engineering group for more information.

Note: All actuator units can be supplied with standard raises up to 24 inches. Special raises up to 20 feet are available upon request. Closed height dimensions may increase for actuators supplied with bellows boots.

Models

Machine Screw Actuator Cut-Away Diagram

MachineScrewDiagram.jpg
  • Because the Duff-Norton machine screw mechanical actuator is produced in many standard models with a wide range of capacities, there is a standard model for almost any requirement. Models can be furnished to 350 Tons capacity.
  • Operated manually or by means of gear motors, machine screw actuator models can be used singly, in tandem or in multiple arrangements.
  • Since most capacities have a uniform lifting speed, added economy can be realized in raising unevenly distributed loads by operating the different capacities in union.
  • Most Duff-Norton machine screw actuator models with higher ratios are self-locking and will hold heavy loads in position indefinitely without creep.
  • They can be used to push, pull, apply pressure and as linear actuators. They are furnished with standard raises in increments of 1 inch.
  • Depending upon size and type of load, models are available with raises up to 20 feet.

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