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Ball Screw Jacks

1/2-to-50-ton capacity. Ball Screw Jacks offer high efficiency and high speed in one linear positioning package. These actuators come in many standard models, or can be custom designed for any application up to 50 tons.

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Features and Benefits

  • Capacity
    1/2 to 50 Tons.
  • Suitable for High Duty Cycles
    The positive action of the low friction ball screw and nut design provides longer life at load and requires less power to achieve a specified thrust.
  • Versatile
    Ball screw actuators can be used individually, in tandem or as part of a larger mechanical system.
  • Long Travel Lengths
    With lifts up to 20 feet, Duff-Norton Ball Screw actuators offer the perfect solution to many linear positioning applications.
  • High Efficiency
    Move loads and apply force more efficiently than other mechanical actuators.
  • Longer Lifespan
    Permit faster operation and longer life under load.
  • Lower Energy Consumption
    Requires less power by reducing screw friction.
  • Synchronization
    Permit synchronization of multiple units.
  • Full Rated Capacity
    Handles full load in tension or compression.
  • Configurations
    40 models available.

    • Specifications

    Performance 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.

    Machine Screw Actuator Stainless Steel

    Capacity (tons)

    		 1/2 1 2H 2 3 5 (HL) 5 10 (HL) 10 20 (HL) 20 25 50*

    Max. Speed Cface Driven (in/min)

    		 — — 287.5 72.0 118.5 287.5 136.5 215.5 102.0 215.5 108.0 81.0 —

    Max. Speed Red. Driven (in/min)

    		 —
    —
    		 57.51 14.4 23.7 57.4 27.2 43 20.4 43.1 21.6 20.1 33.4
     

    Lifting Screw

    Diameter (in)

    		 5/8 3/4 1 1 1-11/64 1-1/2 1-1/2 1-1/2 1-1/2 2-1/4 2-1/4 3 4

    Lead (in)

    		 0.200 0.200 1.000 0.250 0.413 1.000 0.474 1.000 0.474 1.000 0.500 0.660 1.000
     

    Worm Gear Ratios

    Standard

    		 5:1 5:1 6:1 6:1 6:1 6:1 6:1 8:1 8:1 8:1 8:1 10-2/3:1 10-2/3:1

    Optional No. 1

    		 20:1 20:1 24:1 24:1 24:1 24:1 24:1 24:1 24:1 24:1 24:1 32:1 32:1

    Optional No. 2

    		 — — 12:1 12:1 12:1 12:1 12:1 — — — — — —
     

    Turns of Worm for 1 inch Stroke

    Standard

    		 25 25 6 24 14.526 6 12.667 8 16.889 8 16 16.16 10.67

    Optional No. 1

    		 100 100 24 96 58.106 24 50.667 24 50.667 24 48 48.48 32

    Optional No. 2

    		 — — 12 48 29.053 12 25.334 — — — — — —
     

    Worm Torque at No Load (in-lb)

    Standard

    		 0.5 2 10 3 5 20 10 20 15 50 40 40 40

    Optional No. 1

    		 0.5 2 10 3 5 20 10 20 15 50 40 40 40

    Optional No. 2

    		 — — 10 3 5 20 10 — — — — — —
     

    Maximum Horsepower
    per Actuator

    Standard

    		 1/3 1/2 2 2 2 4 4 5 5 5 5 8 15

    Optional No. 1

    		 1/6 1/4 1/2 1/2 1/2 3/4 3/4 1-1/2 1-1/2 1-1/2 1-1/2 2-1/2 6

    Optional No. 2

    		 — — 3/4 3/4 3/4 2 2 — — — — — —
     

    Starting Worm Torque at Full Load (in-lb)

    Standard

    		 10.5 22 180 50 110 500 200 800 350 1375 700 925 2700

    Optional No. 1

    		 5.0 11 80 25 50 206 90 400 175 625 325 475 1500

    Optional No. 2

    		 — — 110 30 68 300 145 — — — — — —
     

    Running Worm Torque at Full Load (in-lb)

    Standard

    		 9.5 21 160 45 100 410 180 700 300 1270 650 825 2200

    Optional No. 1

    		 4.0 10 70 20 45 183 80 290 150 570 300 425 1200

    Optional No. 2

    		 — — 100 25 60 270 125 — — — — — —
     

    Efficiency Rating (%)

    Standard

    		 67.0 60.6 66.3 58.9 65.7 64.7 69.8 56.8 62.8 62.7 61.2 59.7 67.8

    Optional No. 1

    		 39.8 31.8 37.9 33.2 36.5 36.2 39.3 45.7 41.9 46.5 44.2 38.6 41.4

    Optional No. 2

    		 — — 53.0 53.1 54.8 49.1 50.3 — — — — — —
     

    Weight with 6 inch Stroke (Raise) (lb)

    		 2.8 5 20 20 21 40 40 50 50 115 115 235 520
     

    Weight per Additional 1 inch Stroke (Raise) (lb)

    		 0.1 0.3 0.3 0.3 0.4 0.9 0.9 0.9 0.9 1.5 1.5 2.9 5.0
     

    Hold Back Torque at Rated Load (ft-lb)

    Standard

    		 1 1 2 2 7 8 8 24 11 24 24 24 32

    Optional No. 1

    		 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 2 2 2 33

    Optional No. 2

    		 — — 1 1 2 2 2 — — — — — —
     

    Key Torque (in-lb)

    		 35 70 100 175 440 1800 850 3500 1700 7000 3500 6000 17700
     

    Max Worm Speed at Full Load (rpm)

    Standard

    		 2001 1432 700 2521 1146 504 1146 394 900 229 450 545 350

    Optional No. 1

    		 2101 1432 394 1261 630 229 252 236 540 151 291 332 252

    Optional No. 2

    		 — — 430 5875 695 420 869 — — — — — —
     

    Maximum Load at Full Horsepower and 170 rpm (lb)

    Standard

    		 1150 1601 1459 5875 3830 2585 6384 4104 9855 3927 8489 14018 17250

    Optional No. 1

    		 1223 1556 458 2729 1734 377 2126 1791 4878 280 1968 5751 8942

    Optional No. 2

    		 — — 680 3557 2096 1858 4595 — — — — — —

    Notes:
    - Hold Back Torque is restraining torque at the worm shaft to keep load from running down.
    - Lifting torques are proportional to load, down to 25% of rated load.
    - 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.
    * Does your ball screw application require more than 50 tons? Please contact our Customer Service group to explore our specialty options for higher load ratings up to 100 tons.

    Documents

    Brochures & Catalogs

    [Brochure] Duff-Norton Product Capabilities Brochure [Catalogs] Mechanical Actuator (Screw Jacks) Design Guide

    Manuals & Supplements

    [Technical Bulletin] Screw Jack Application Analysis Form

    Product & Data Sheets

    [Product Sheet] Ball Screw Actuator Product Sheet

    Drawings & Diagrams

    [Dimension Drawing] 10 Ton Ball Screw Dimensions [Dimension Drawing] 1/2 Ton Ball Screw Dimensions [Dimension Drawing] 1 Ton Ball Screw Dimensions [Dimension Drawing] 20 Ton Ball Screw Dimensions [Dimension Input Drawing] 25 Ton Ball Screw Dimensions [Dimension Drawing] 2 Ton Ball Screw Dimensions [Dimension Drawing] 3 Ton Ball Screw Dimensions [Dimension Drawing] 50 Ton Ball Screw Dimensions [Dimension Drawing] 5 Ton Ball Screw Dimensions