Machine Screw Jacks

Joyce worm gear machine screw jacks lift and precisely position loads (250 pounds to 250 tons). Upright or inverted jacks operate at full capacity in tension or compression. WJ and RWJ, single lead jacks are self-locking. DWJ and DRWJ, double lead jacks offer increased travel speed and require a brake or external locking device to hold position.

  • Alloy steel input shafts
  • Aluminum bronze wormgears
  • Tapered or ball thrust bearings provide rugged reliability
  • Double input shafts standard
  • Protective boots available
  • Anti-backlash devices available
  • Customized mechanical jacks can be made to your specifications
  • Custom finishes available

wormgear jack cut away illustration

Parts list and exploded views are included in the O&M Manual. The serial number is attached to the product housing.

machine screw jack    REQUEST A QUOTE

 

O & M Manual

Ordering Information

Serial Number Example

Specifications

 

 2D/3D Drawings or JAX Online

Product Options

Anti-backlash Devices
  • Available for machine screw jacks
  • Available for metric (trapezoidal) jacks
  • Limits lifting screw endplay
  • Anti-backlash Devices

Encoders
  • Standard 200 or 1024 PPR
  • Quadrature wave form
  • Stainless steel encoder
  • Absolute encoder
  • Encoders

Finishes
  • Enamel finish (standard)
  • Epoxy finish
  • STEEL IT® epoxy
  • Outdoor paint process
  • Custom finishes available
  • Anodized (250-lb to 1-ton)
  • Nickel, Xylan®, Armoloy®
  •  Finishes

  

   

Follower Nuts
  • For KFTN jack
  • For translating jack

Hand Wheels
  • 4" – 12" dia. (standard)
  • Aluminum (standard)
  • Stainless steel available
  •  Hand Wheels

 

Input Shaft (worm)
  • Square or hex to fit tool
  • Special lengths
  • 17-4 stainless steel available
  • Metric diameters available
  • One side can be cut off
  • Other modifications available
  • Input shaft cover available

Limit Switches
  • Rotary cam (2-4 switches)
  • SPDT standard
  • DPDT available
  • Explosion proof available
  • Limit Switches

Lubrication
  • Standard grease temperature range (40°F to 220°F)
  • Low temperature option
  • High temperature option
  • Food grade option

Machine Screws
  • Right hand thread standard
  • Left hand thread available on many models
  • Special material available
  • Special pitch/lead available
  • Special finishes available
  • Special machining options
  • Special end conditions available

Mechanical Counters

 

Motor Mounts
  • NEMA mounts available on 2-ton to 20-ton wormgear jacks and electric cylinders
  • NEMA mounts included on integrated actuators
  • Servo motor mounts available on 2-ton to 10-ton jacks and electric cylinders, special mounts available
  • Custom mounts available
  • Motor Mounts and Stock Motors

Potentiometers
  • 0-10V (POTA)
  • 4-20mA (POTB)
  • 0-10V with limit switches (POTC)
  • 4-20mA with limit switches(POTD)
  • IP65
  • Potentiometers

Protective Boots
  • Protection from dirt and dust
  • Guard against moisture
  • Guard against corrosive contaminants
  • Neoprene coated nylon (std)
  • Special materials available
  • Boot Material Chart
  • Protective Boots

Screw Stops
  • Standard on ComDRIVEs
  • Adjustable
  • Bolt- on

Thrust Rings
  • Used in applications where static loads exceed jack capacity

Wormgear Sets
  • Right hand gear set standard
  • Left hand available on many models
  • 25:1 ratio option available on several models

Ordering Information

Sample Part Number:

Click on the part number to reveal additional informaton about jack designs and shaft codes.


Model Number

Miniature 1-Ton 2-Ton 2-Ton Reverse Base 3-Ton 5-Ton 10-Ton 15-Ton 20-Ton
WJ250
WJ500*
WJ1000		 WJ51
WJ201		 WJT62
WJT122
WJT242
WJT252		 RWJT62
RWJT122
RWJT242
RWJT252		 WJ63
WJ123
WJ243
WJ253		 WJT65
WJT125
WJT245
WJT255		 WJ810
WJ2410
WJ2510		 WJ815
WJ2415
WJ2515		 WJ820
WJ2420
WJ2520
    DWJ62*
DWJ122*
DWJ242*		 DRWJ62*
DRWJ122*
DRWJ242*		 DWJ63*
DWJ123*
DWJ243*		 DWJ65*
DWJ125*
DWJ245*		 DWJ810*
DWJ2410*		 DWJ815*
DWJ2415*		 DWJ820*
DWJ2420*
25-Ton 30-Ton 35-Ton 50-Ton 50-Ton Reverse Base 75-Ton 100-Ton 150-Ton 250-Ton
WJ1125
WJ3225		 WJ1130
WJ3230		 WJ1135
WJ3235		 WJT1150
WJT3250		 RWJT1150
RWJT3250		 WJ1175
WJ3275		 WJ12100
WJ36100		 WJ12150
WJ36150		 WJ50250
DWJ1125*
DWJ3225*		 DWJ1130*
DWJ3230*		              

Important Note: *Not self-locking, may lower under load. Brake motors or external locking systems are recommended.
D: Double Lead Screw
R: Reverse Base Jack, (only available on 2-ton and 50-ton jacks).

Jack Configuration

U=Upright

I=Inverted

End Conditions

1=T1
(plain end)

2=T2
(load pad)

3=T3
(threaded end)

4=T4
(male clevis)

Jack Designs

S=Translating

K=Keyed for Non Rotation

N=Traveling Nut

D=Double Clevis

R=KFTN Trunnion*
T=Trunnion*

* Standard trunnion mounts available on 2-ton through 20-ton jacks.

Machine Screw Jack Rise

Rise is travel expressed in inches and not the actual screw length.

Left Side Shaft Code

Right Side Shaft Code

XXXX=Remove
STDX=Standard

XXXX=Remove
STDX=Standard

 

Optional Shaft Codes

Screw Stops and Boots

Screw stops are optional on machine screw jacks. When specified, the closed height of the jack and/or the protection tube length may be increased. When boots are added to machine screw jacks, the closed height of the jack may be increased.

Mechanical Counters

CNT0=0.001" Increments
Note: Contact Joyce/Dayton for availability and options.

Hand Wheels

HW04=4" dia
HW06=6" dia
HW08=8" dia
HW10=10" dia
HW12=12" dia

Geared Potentiometers

POTA=0-10V (IP65)
POTB=4-20MA (IP65)
POTC=0-10V w/2 switches*
POTD=4-20MA w/2 switches*
*Optional IP65 rating available

Encoders and Electronic Liit Switches

ENCX=Encoder
ELS2=2 Position Electronic Switch
ELS4=4 Position Electronic Switch
ELS6=6 Position Electronic Switch

Motor for Systems and Direct Drives

  • All standard motors are 3-phase, 208-230/460 VAC or 230/460 VAC. Other motor options are available. Specify the appropriate motor size from the chart on the right.
  • Refer to the "Additional Options" chart on the preceding page as needed.
  • Brake motors (M2) are recommended for jacks that are not self-locking, and jacks with double lead screws.
  • If the motor frequency will be varied to provide a "soft" start an inverter duty motor may be required.

Motors

Size Code
1/4 HP K
1/3 HP A
1/2 HP B
3/4 HP C
1 HP D
1-1/2 HP E
2 HP F
3 HP L
5 HP G
7-1/2 HP H
10 HP I
15 HP J

Motor Mounts

Ordering Example:
MMA A (Motor code from chart above)

MMA=56C
MMB=140TC
MMC=180TC
MMD=210TC

Standard motor adapters are aluminum

Mechanical Limit Switches

Ordering Example:
LA (Models) 1(Number of DPDT Switches) 3(Available Positions)

Model Code   Available Positions
LS7-402 LI

Number of DPDT Switches

NOTE: Will always be 0 for LS7 models

   1 2* 3 4 5 6* 7 8
LS8-402 LA Left Side Shaft Options
LS8-504 LB
LS9-502 LC
LS9-503 LD Right Side Shaft Options
LS9-504 LE
LS9-505 LF
LS9-506 LG
  • 2, 3, 5, 10, 15, and 20 ton jacks are available with positions #1, #3, and #5
  • 25, 30, 35, 50, 75, 100, and 150 ton jacks are available with positions #1, #4, #7, and #8

*These positions are not standard. Contact Joyce/Dayton with your requirements.
LS9-507 LH

Additional Options

  • X=Standard Jack, no additional options
  • S=Additional Specification Required (comment as necessary)

Anti-Backlash

  • A=Split Nut
  • A90=A90 Design
  • A95=A95 Design

Protective Boots

  • B=Protective Boot
  • D=Dual Protective Boot

Finishes

  • F1=Do Not Paint
  • F2=Epoxy Paint
  • F3=Outdoor Paint Process

Motor Options

  • M1=Less Motor
  • M2=Brake Motor
  • M3=Single Phase Motor (120VAC)
  • M4=50Hz Motor

Grease/Seals

  • H1=High Temperature Operation
  • H2=Food Grade

Screw Stops

  • ST0=Extending
  • ST1=Retracting
  • ST2=Both
  • Specify as many options as needed

Product Specifications

MODELCPTYSCRW DIAM (INCH)THRD PITCH/ LEADWORM GEAR RATIOWORM SHAFT TURNS FOR 1" TRAVELTARE TORQUE (INCH LBS.)STARTING TORQUE (INCH LBS.)OPERATING TORQUE (INCH LBS.)EFFICIENCY 
RATING % APPROX.		SCREW TORQUE (INCH LBS.)BASIC JACK WEIGHT (LBS).JACK WEIGHT PER INCH TRAVEL (LBS.)
WJ250 250 lbs. 1/2 .125 pitch
STUB ACME		 5:1 40 1 .025W* .018W* @ 500 RPM 23.0 .050W* 1.2 0.1
WJ500 500 lbs. 5/8 .125 pitch/.250 lead
STUB ACME		 5:1 20 1 .041W* .030W* @ 500 RPM 27.2 .079W* 1.3 0.1
WJ1000 1,000 lbs. 5/8 .125 pitch
STUB ACME		 5:1 40 1 .030W* .021W* @ 500 RPM 19.9 .059W* 1.3 0.1
WJ51 1 ton 3/4 .200 pitch
ACME 2C		 5:1 25 3 .038W* .026W* @ 500 RPM 25 .075W* 6 0.3
WJ201 1 ton 3/4 .200 pitch
ACME 2C		 20:1 100 3 .017W* .009W* @ 500 RPM 15.9 .075W* 6 0.3
(R)WJT62 2 ton 1 .250 pitch
ACME 2C		 6:1 24 4 .041W* .028W* @ 500 RPM 24.2 .098W* 15 0.3
(R)WJT122 2 ton 1 .250 pitch
ACME 2C		 12:1 48 4 .025W* .015W* @ 500 RPM 22.0 .098W* 15 0.3
(R)WJT242 2 ton 1 .250 pitch
ACME 2C		 24:1 96 4 .018W* .009W* @ 500 RPM 18.3 .098W* 15 0.3
(R)WJT252 2 ton 1 .250 pitch
ACME 2C		 25:1 100 4 .015W* .0085W* @ 500 RPM 17.0 .098W* 15 0.3
D(R)WJ62 2 ton 1 .250 pitch
.500 lead 
ACME 2C		 6:1 12 4 .057W* .039W* @ 500 RPM 33.7 .139W* 15 0.3
D(R)WJ122 2 ton 1 .250 pitch
.500 lead 
ACME 2C		 12:1 24 4 .035W* .022W* @ 500 RPM 30.5 .139W* 15 0.3
D(R)WJ242 2 ton 1 .250 pitch
.500 lead 
ACME 2C		 24:1 48 4 .025W* .013W* @ 500 RPM 25.4 .139W* 15 0.3
WJ63 3 ton 1 .250 pitch
ACME 2C		 6:1 24 6 .040W* .029W* @ 500 RPM 24.3 .098W* 17 0.4
WJ123 3 ton 1 .250 pitch
ACME 2C		 12:1 48 6 .025W* .016W* @ 500 RPM 22.2 .098W* 17 0.4
WJ243 3 ton 1 .250 pitch
ACME 2C		 24:1 96 6 .017W* .009W* @ 500 RPM 18.5 .098W* 17 0.4
WJ253 3 ton 1 .250 pitch
ACME 2C		 25:1 100 6 .0155W* .009W* @ 500 RPM 17.8 .098W* 17 0.4
DWJ63 3 ton 1 .250 pitch
.500 lead 
ACME 2C		 6:1 12 6 .055W* .041W* @ 500 RPM 33.8 .139W* 17 0.4
DWJ123 3 ton 1 .250 pitch
.500 lead 
ACME 2C		 12:1 24 6 .034W* .022W* @ 500 RPM 30.7 .139W* 17 0.4
DWJ243 3 ton 1 .250 pitch
.500 lead 
ACME 2C		 24:1 48 6 .024W* .013W* @ 500 RPM 25.6 .139W* 17 0.4
WJT65 5 ton 1 ½ .375 pitch
STUB 
ACME		 6:1 16 10 .065W* .044W* @ 300 RPM 23.0 .151W* 32 0.7
WJT125 5 ton 1 ½ .375 pitch
STUB 
ACME		 12:1 32 10 .041W* .025W* @ 300 RPM 20.6 .151W* 32 0.7
WJT245 5 ton 1 ½ .375 pitch
STUB 
ACME		 24:1 64 10 .029W* .015W* @ 300 RPM 16.7 .151W* 32 0.7
WJT255 5 ton 1 ½ .250 pitch
ACME 2C		 25:1 100 10 .022W* .011W* @ 300 RPM 13.4 .131W* 32 0.7
DWJ65 5 ton 1 ½ .250 pitch
.500 lead 
ACME 2C		 6:1 12 10 .072W* .050W* @ 300 RPM 26.8 .171W* 32 0.7
DWJ125 5 ton 1 ½ .250 pitch
.500 lead 
ACME 2C		 12:1 24 10 .045W* .028W* @ 300 RPM 23.9 .171W* 32 0.7
DWJ245 5 ton 1 ½ .250 pitch
.500 lead 
ACME 2C		 24:1 48 10 .033W* .017W* @ 300 RPM 19.6 .171W* 32 0.7
WJ810 10 ton 2 .500 pitch
ACME 2C		 8:1 16 20 .061W* .043W* @ 200 RPM 23.1 .195W* 43 1.3
WJ2410 10 ton 2 .500 pitch
ACME 2C		 24:1 48 20 .030W* .018W* @ 200 RPM 18.8 .195W* 43 1.3
WJ2510 10 ton 2 .250 pitch
ACME 2C		 25:1 100 20 .024W* .014W* @ 200 RPM 11.3 .161W* 43 1.3
DWJ810 10 ton 2 .333 pitch
.666 lead ACME 2C		 8:1 12 20 .070W* .062W* @ 200 RPM 31.9 .228W* 43 1.3
DWJ2410 10 ton 2 .333 pitch
.666 lead ACME 2C		 24:1 36 20 .035W* .026W* @ 200 RPM 25.9 .228W* 43 1.3
WJ815 15 ton 2 ¼ .500 pitch
ACME 2C		 8:1 16 30 .069W* .047W* @ 200 RPM 21.1 .210W* 59 1.4
WJ2415 15 ton 2 ¼ .500 pitch
ACME 2C		 24:1 48 30 .036W* .020W* @ 200 RPM 16.6 .210W* 59 1.4
WJ2515 15 ton 2 ¼ .250 pitch
ACME 2C		 25:1 100 30 .026W* .015W* @ 200 RPM 10.2 .178W* 59 1.4
DWJ815 15 ton 2 ¼ .333 pitch
.666 lead ACME 2C		 8:1 12 30 .079W* .058W* @ 200 RPM 34.4 .244W* 59 1.4
DWJ2415 15 ton 2 ¼ .333 pitch
.666 lead ACME 2C		 24:1 36 30 .041W* .025W* @ 200 RPM 27.0 .244W* 59 1.4
WJ820 20 ton 2 ½ .500 pitch
ACME 2C		 8:1 16 40 .075W* .051W* @ 200 RPM 19.6 .227W* 77 1.9
WJ2420 20 ton 2 ½ .500 pitch
ACME 2C		 24:1 48 40 .039W* .022W* @ 200 RPM 15.4 .227W* 77 1.9
WJ2520 20 ton 2 ½ .250 pitch
ACME 2C		 25:1 100 40 .029W* .016W* @ 200 RPM 9.4 .194W* 77 1.9
DWJ820 20 ton 2 ½ .375 pitch
.750 lead ACME 2C		 8:1 10.67 40 .088W* .061W* @ 200 RPM 24.5 .272W* 77 1.9
DWJ2420 20 ton 2 ½ .375 pitch
.750 lead ACME 2C		 24:1 32 40 .046W* .026W* @ 200 RPM 19.3 .272W* 77 1.9
WJ1125 25 ton 3 ⅜ .666 pitch STUB 
ACME		 11:1 16 50 .088W* .055W* @ 200 RPM 18.3 .313W* 164 3.1
WJ3225 25 ton 3 ⅜ .666 pitch STUB 
ACME		 32:1 48 50 .053W* .025W* @ 200 RPM 13.5 .313W* 164 3.1
DWJ1125 25 ton 3 ⅜ .562 pitch 1.125 lead 
ACME 2C		 11:1 9.5 50 .106W* .067W* @ 200 RPM 25.1 .384W* 164 3.1
DWJ3225 25 ton 3 ⅜ .562 pitch 1.125 lead 
ACME 2C		 32:1 28.5 50 .063W* .030W* @ 200 RPM 18.6 .384W* 164 3.1
WJ1130 30 ton 3 ½ .666 pitch
ACME 2C		 11:1 16 60 .088W* .055W* @ 200 RPM 18.3 .313W* 164 3.0
WJ3230 30 ton 3 ½ .666 pitch
ACME 2C		 32:1 48 60 .052W* .025W* @ 200 RPM 13.5 .313W* 164 3.0
DWJ1130 30 ton 3 ½ .5625 pitch 1.125 lead 
ACME 2C		 11:1 9.5 60 .107W* .067W* @ 200 RPM 25.1 .384W* 164 3.0
DWJ3230 30 ton 3 ½ .5625 pitch 1.125 lead 
ACME 2C		 32:1 28.5 60 .064W* .030W* @ 200 RPM 18.6 .384W* 164 3.0
WJ1135 35 ton 3 ¾ .666 pitch
ACME 2C		 11:1 16 70 .093W* .057W* @ 200 RPM 17.4 .328W* 240 3.4
WJ3235 35 ton 3 ¾ .666 pitch
ACME 2C		 32:1 48 70 .055W* .026W* @ 200 RPM 12.9 .328W* 240 3.4
(R)WJT1150 50 ton 4 ½ .666 pitch
ACME 2C		 11:1 16 100 .095W* .063W* @ 150 RPM 15.8 .378W* 387 6.1
(R)WJT3250 50 ton 4 ½ .666 pitch
ACME 2C		 32:1 48 100 .050W* .027W* @ 150 RPM 12.4 .378W* 387 6.1
WJ1175 75 ton 5 .666 pitch
ACME 2C		 11:1 16 155 .107W* .067W* @ 150 RPM 14.8 .418W* 610 6.5
WJ3275 75 ton 5 .666 pitch
ACME 2C		 32:1 48 155 .056W* .028W* @ 150 RPM 11.7 .418W* 610 6.5
WJ12100 100 ton 6 .750 pitch
ACME 2C		 12:1 16 205 .112W* .072W* @ 90 RPM 13.9 .495W* 1010 10.0
WJ36100 100 ton 6 .750 pitch
ACME 2C		 36:1 48 205 .059W* .031W* @ 90 RPM 10.8 .495W* 1010 10.0
WJ12150 150 ton 7 1.00 pitch
ACME 2C		 12:1 12 300 .134W* .084W* @ 90 RPM 15.7 .595W* 1350 12.2
WJ36150 150 ton 7 1.00 pitch
ACME 2C		 36:1 36 300 .070W* .037W* @ 90 RPM 12.1 .595W* 1350 12.2
WJ50250 250 ton 9 1.00 pitch
ACME 2C		 50:1 50 500   .036W* @ 60 RPM 8.8 .711W* 3415 21.0

 

Important Note: Series DWJ double lead and WJ500 screw jacks are not self-locking. Brake motors or external locking systems are recommended.
(R): Reverse Base Jack.
*W: Load in pounds.
Tare Torque: Initial torque to overcome seal and normal assembly drag. (This value must be added to starting torque or operating torque values.)
Starting Torque: Torque value required to start moving a given load (dissipates to operating torque values once the load begins moving).
Operating Torque: Torque required to continuously raise a given load at the input RPM listed. NOTE: If your actual input RPM is 20% higher or lower than the listed RPM, please refer to our JAX program to determine actual torque values at your RPM.
Screw Torque: Torque required to resist screw rotation (Translating Design Jacks) and traveling nut rotation (Keyed for Traveling Nut Design Jacks).
Lead: The distance traveled axially in one rotation of the lifting screw.
Pitch: The distance from a point on a screw thread to a corresponding point on the next thread, measured axially.

Note: This chart is provided as a reference only. For specific information such as column loading, allowable continuous travel, and performance factors please refer to JAX online software of contact joyce.


Boots and special finishes are available for Joyce Screw jacks. Choose from a variety of boot materials and designs for the jacks you select (translating, keyed, or KFTN). Joyce offers premium finishes, outdoor paint process, and custom finishes to meet your specifications. We have a hassle-free process for delivering what you need.

What you need to know to specify screw jacks in industrial application.

Jacks are rated based on their static thrust capacity from 250-pounds to 250-tons. But the selection of the best jack for the application requires further consideration.

  1. When jacks are loaded in compression one must consider the load carrying capacity of the lifting screw (column load). How high do you need to lift the load? Choose a jack whose lifting screw is stout enough to handle the load at full rise.
  2. Consider the travel speed of the DYNAMIC load. The speed at which the load will be moved is a limiting factor. How fast do you need to move the load? Sometimes double lead machine screw jacks or ball screw jacks are a better choice in a given application.
  3. How frequently will the jack need to move the load? Remember that heat builds up between the machine screw and nut during normal operation. Duty cycles for machine screw jacks must include periods of rest to dissipate that heat.

Which jack design is best for your application? Once loads, duty cycles, and travel speeds are established, designers must select which of the three jack design to use.

  • Translating Design Jacks are most often selected. With this design, a driven input worm acts on an internal worm gear causing the lifting screw to extend or retract. Operation requires that rotation of the lifting screw be prevented. This rotation it restrained whenever two or more jacks are tied to the same load.
  • Keyed Design Jacks are used any time rotation of the lifting screw is not restrained. For instance, when you must lift the jack to meet a load. This is how they work: A key, fixed to the jack housing and inserted into a keyway milled into the length of the lifting screw forces the lifting screw to translate without rotating.
  •  Keyed For Travelign Nut Design Jacks (KFTN) are another option. These jacks have a fixed length lifting screw that rotates. Loads are attached to a flanged “traveling” nut that translates up and down the length of the rotating screw. This type of jack is ideal for applications that cannot accommodate a screw protection tube or that require a flush mount

Take the work out of using screw jacks in systems

Joyce/Dayton screw jacks and lifting systems offer wide-ranging lifting and positioning solutions for diverse industries. Our robust jacks reliably move and accurately position loads up to 250-tons. Joyce configures jacks with components such as motors, gear reducers, shafting, coupling, and motion control devices to create complete multi-jack systems.

Tell us what you need or use our exclusive JAX® Online software (it’s free). We will put together complete systems with single or multiple screw jacks for you. The software is great because it calculates motor horsepower and shaft diameters and torques. There are several common arrangements, but you can design your own.

Look for our next generation JAX® Online browser-based software soon. 

Where are worm gear machine screw jacks used?

Worm gear machine screw jacks are the workhorses of the lifting industry, available in static capacities up to 250-tons. They are commonly used to lift, hold, and position loads. Examples include: Platform lifts, Damper adjustments, Ergonomic lifts, Maintenance lifts, Roll adjustments, Earth Station Antennas, Drilling equipment, Solar Trackers, Conveyor adjustments, Packaging equipment, Gate adjustments, Dam adjustment, and Mine door openers.