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    53 Products

    One-Way Clutches

    Since they transfer torque in one direction and spin freely in the other, these clutches are useful in applications where you don’t want motion to reverse, such as in backstopping, indexing, and overrunning. For example, they can be used to prevent a conveyor from reversing direction.
    When choosing a clutch, consider how much torque you need to transfer. You should also consider how the clutch will attach to your mounted component.
    Sprag Engagement—Flush Hub
    Image of Product. Front orientation. Clutches. One-Way Clutches, Sprag Engagement—Flush Hub.
    Image of Product. Front orientation. Clutch Covers.

    Covers

    Image of ProductInUse. Torque Arm Shown Installed. Front orientation. Clutch Torque Arms.
    Image of Product. Front orientation. Clutch Torque Arms.

    Torque Arm Shown Installed

    Torque Arms

    Sprag clutches handle higher torque than roller clutches because they have more contact points. This makes them best for backstopping applications.
    Clutches with a flush hub have a precision ground outer race, so they can be press fit directly into a component and positioned anywhere along the length of your shaft. They also have mounting holes on their face you can use to secure your component or an anti-rotation device, such as a torque arm, for a different backstopping setup.
    Through Shaft—Through-shaft clutches regulate torque transmission between an input shaft and a mounted component.
    Slip-Fit Shaft Mount—Clutches that mount to shafts with a slip fit must be secured with a shaft collar or in some other way that prevents them from moving along the length of your shaft.
    Covers—Covers protect you from rotating equipment when the clutch is mounted to the end of the shaft.
    Torque Arms—Clutch torque arms work as an anchor for clutches in backstopping applications. Mount to the outer race of your clutch and a stationary piece of equipment.
    Clutches
    Covers
    Torque Arms
    Max. Rotation
    Speed, rpm
    Shaft
    Clockwise or
    Counterclockwise Drive
    For Shaft
    Dia.
    For Shaft
    Type
    Max. Torque,
    ft·lbf
    Inner-Race
    Outer-Race
    OD
    Overall
    Lg.
    Material
    Keyway Wd. ×
    Keyway Dp.
    Mount
    Type
    Each
    Each
    Each
    Through Shaft
    1 3/4"Keyed2,2502,2007505 3/8"3 3/4"Steel
    3/8" × 3/16"Slip Fit4550N250000000004550N20300000004550N3030000000
     

    High-Torque Flexible Shaft Couplings

    Image of System. Front orientation. Contains Annotated. Flexible Shaft Couplings. High-Torque Flexible Shaft Couplings.
    Image of System. (Each Component Sold Separately). Front orientation. Exploded view. Contains Annotated, MultipleImages. Flexible Shaft Couplings. High-Torque Flexible Shaft Couplings.

    (Each Component Sold Separately)

    With a rugged roller-chain design, these couplings provide excellent torque and angular misalignment capacities. Lubrication is required. Fasten to your shaft by tightening the set screws, which bite into the shaft to hold it.
    A complete coupling consists of two hubs and one roller chain (each component sold separately). Complete couplings meet ANSI B29.23M-1995.
    Optional covers retain grease lubrication and provide protection from abrasion and corrosion.
    Hubs
    Steel Roller Chain
    Orange
    Nylon Covers
    Misalignment Capability
    Roller Chain
    Overall
    Lg.
    OD
    OD with
    Cover
    For Shaft
    Type
    For Rotary
    Motion
    For Shaft
    Dia.
    Each
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    Parallel
    Angular
    No.
    Standard
    Each
    Each
     
    Steel Hubs
    3 29/64"5"6 3/8"KeyedContinuous1 3/4"6407K440000003,00010,9000.012"1.5°60-2ANSI6407K540000006407K740000000
     

    High-Torque Set Screw Flexible Shaft Couplings

    Image of System. Front orientation. Contains Annotated, MultipleImages. Flexible Shaft Couplings. High-Torque Set Screw Flexible Shaft Couplings.
    Image of System. Front orientation. Contains Annotated, MultipleImages. Flexible Shaft Couplings. High-Torque Set Screw Flexible Shaft Couplings.
    The thick split spider on these couplings takes on twice as much torque as standard split spiders, while a set screw holds the hubs in place on your shaft. Also known as jaw couplings, use them to connect motors to pumps, mixers, and other high-torque equipment. You don’t need to lubricate them.
    For a complete coupling, you’ll need two hubs, one split spider, and a split spider cover (all sold separately).
    Hubs attach to the end of your shaft.
    Split spiders cushion between the two hubs to dampen vibration, reduce shocks, and handle shaft misalignment, extending the life of bearings, seals, and motors. You can replace them without having to remove the hubs or move your shaft and equipment around, which reduces the risk of needing to realign the shaft.
    Split spider covers hold the spider in place.
    Hubs
    Steel Split
    Spider Covers
    Overall
    Lg.
    OD
    For Shaft
    Type
    For Rotary Motion
    For Shaft
    Dia.
    Each
    Each
     
    Steel Hubs, Split Spiders
    4 29/32"3 3/16"KeyedForward/Reverse, Start/Stop1 3/4"3565N300000003565N63000000
    6 1/16"3 33/64"KeyedForward/Reverse, Start/Stop1 3/4"3565N90000003565N64000000
     
    Urethane Split Spiders

    High-Speed Vibration-Damping Flexible Shaft Couplings

    Image of System. Front orientation. Contains Annotated. Flexible Shaft Couplings. High-Speed Vibration-Damping Flexible Shaft Couplings.
    Image of System. (Each Component Sold Separately). Front orientation. Exploded view. Contains Annotated, MultipleImages. Flexible Shaft Couplings. High-Speed Vibration-Damping Flexible Shaft Couplings.

    (Each Component Sold

    Separately)

    Use these gear-shaped couplings for high-speed and high-torque applications. A rubber center allows flexing so couplings can take on multiple types of misalignment while damping vibration and shock. With no metal-to-metal contact, there’s no need for lubrication. Fasten to your shafts by tightening the set screws, which bite into the shaft to hold it.
    A complete coupling consists of two hubs and one center (each component sold separately).
    Hubs have a keyway, except hubs for 1⁄4" and 3⁄8" shaft dia. do not have a keyway.
    Hubs
    Shaft Coupling Centers
    Misalignment Capability
    Overall
    Lg.
    OD
    For Rotary
    Motion
    For Shaft
    Dia.
    Each
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    Parallel
    Angular
    Axial
    Temp. Range,
    ° F
    Material
    Each
    Cast Iron Hubs
    3 15/16"4 5/8"Continuous1 3/4"6507K50000005,2507250.02"0.125"-30 to 275TPE
    6507K74000000
    5 1/16"6 23/64"Continuous1 3/4"6507K70000003,7501,8000.025"0.125"-30 to 275TPE
    6507K7600000
    5 11/16"7 1/2"Continuous1 3/4"6507K80000003,6002,8750.025"0.125"-30 to 275TPE
    6507K77000000
     

    Set Screw Flexible Shaft Couplings

    Image of System. Hubs, Split Spider, and Retaining Ring Shown Assembled. Front orientation. Contains Annotated. Flexible Shaft Couplings. Set Screw Flexible Shaft Couplings.
    Image of System. (Each Component Sold Separately). Front orientation. Contains Annotated. Flexible Shaft Couplings. Set Screw Flexible Shaft Couplings.

    Hubs, Split Spider, and

    Retaining Ring Shown

    Assembled

    (Each Component Sold

    Separately)

    Image of System. Hubs and Spider Shown Assembled. Front orientation. Contains Annotated. Flexible Shaft Couplings. Set Screw Flexible Shaft Couplings.
    Image of System. (Each Component Sold Separately). Front orientation. Exploded view. Contains Annotated. Flexible Shaft Couplings. Set Screw Flexible Shaft Couplings.

    Hubs and Spider Shown

    Assembled

    (Each Component Sold

    Separately)

    Each hub includes a set screw (unless noted), which bites into your shaft to hold the coupling in place. Also known as Lovejoy® couplings, these three-piece couplings have a spider-shaped cushion between two hubs to reduce shock and handle minor shaft misalignment.
    A complete coupling consists of two hubs and one spider, or two hubs, one split spider, and one retaining ring (all components sold separately). Split spiders are easier to install and replace than standard spiders because there’s no need for tools or removing your hubs. Twist-lock them in place using a retaining ring.
    Buna-N—Buna-N spiders provide good vibration damping and chemical resistance.
    Hytrel—Hytrel spiders provide fair vibration damping and excellent chemical resistance.
    Polyurethane Rubber—Polyurethane spiders and split spiders provide fair vibration damping and good chemical resistance.
    Hubs
    Buna-N Spiders
    Hytrel Spiders
    Polyurethane Spiders
    Misalignment Capability
    Misalignment Capability
    Misalignment Capability
    Overall
    Lg.
    OD
    For Shaft
    Type
    For Rotary Motion
    For Shaft
    Dia.
    Each
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    Parallel
    Angular
    Temp. Range,
    ° F
    Spider
    Material
    Each
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    Parallel
    Angular
    Temp. Range,
    ° F
    Spider
    Material
    Each
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    Parallel
    Angular
    Temp. Range,
    ° F
    Spider Material
    Each
     
    Iron Hubs
    4 1/2"3 3/4"KeyedForward/Reverse, Start/Stop1 3/4"6408K1900000005,0001,2400.015"-40 to 212Buna-N
    6408K810000003,6003,7050.015"0.5°-55 to 245Hytrel6408K9800000003,6001,8600.015"-30 to 160Polyurethane Rubber
    2410K190000000
    4 7/8"4 1/2"KeyedForward/Reverse, Start/Stop1 3/4"6408K210000005,0001,7250.015"-40 to 212Buna-N
    6408K82000005,0004,6800.015"0.5°-55 to 245Hytrel6408K99000000———0
    5 11/32"5"KeyedForward/Reverse, Start/Stop1 3/4"6408K220000004,2002,3400.015"-40 to 212Buna-N
    6408K62000004,2006,2250.015"0.5°-55 to 245Hytrel6408K64000000———0
     

    Keyless Locking Rigid Shaft Couplings for Overhung Loads

    Support the weight of a motor and transfer torque to another shaft at the same time with these couplings. Often used to hang motors from conveyor belts and other driven equipment, or to connect long sections of shafts, these couplings eliminate the need for support brackets. Use a torque arm to prevent hanging motors from spinning.
    The clamping screws on the coupling face squeeze two outer collars against an inner ring, pressing it tight against shafts to lock them together. This ring-locking mechanism leaves no room for backlash, meaning that all of the turning force created by the motor is passed on to the second shaft. These couplings grip shafts of any shape, so you can install them onto existing keyways and splines without using a key.
    To install these couplings, use a torque wrench to tighten each screw to the fastener tightening torque listed for each coupling size. To remove, gradually loosen each screw in sequence until you can slide the coupling on the shaft. Warning: Do not remove any clamping screws from the coupling until the outer collars are separated from the inner ring. The ring is under tension, and a sudden release of the collars can cause serious injury.
    Overhung load capacity is the amount of downward force that a coupling can withstand from a motor or other object that it is supporting. To calculate the overhung load, measure the distance from the center of the coupling to the center of gravity of the motor. Multiply that distance by the combined weight of the motor and the portion of the shaft between the coupling and the motor. Do not exceed the overhung load capacity for a coupling.
    Steel
    Image of Product. Front orientation. Rigid Shaft Couplings. Keyless Locking Rigid Shaft Couplings for Overhung Loads .
    For Shaft
    Dia.
    Overall
    Lg.
    OD
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    Fastener Tightening
    Torque, in·lbf
    Overhung Load
    Cap., in·lbf
    For Rotary Motion
    Each
    For Keyed, Round, and Splined Shafts
    1 3/4"2 3/16"3 3/4"8,00020,0252645,005Forward/Reverse, Start/Stop, Continuous3456N140000000
     

    Ultra-High-Torque Flexible Shaft Couplings

    Image of System. Front orientation. Contains Annotated. Flexible Shaft Couplings. Ultra-High-Torque Flexible Shaft Couplings.
    Image of System. (Each Component Sold Separately). Front orientation. Exploded view. Contains Annotated, MultipleImages. Flexible Shaft Couplings. Ultra-High-Torque Flexible Shaft Couplings.

    (Each Component Sold Separately)

    With a rigid gear design, these steel couplings transmit more torque than other couplings of the same size. Lubrication is required. To install, heat the hubs to expand them slightly and fit them onto the shaft. When they cool, hubs shrink to fit the shaft tightly.
    A complete coupling consists of two hubs, one sleeve, and one seal kit (each component sold separately).
    Hubs
    Steel Sleeves
    Seal Kits
    Misalignment Capability
    Overall
    Lg.
    OD
    For Shaft
    Type
    For Rotary
    Motion
    For Shaft
    Dia.
    Each
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    Parallel
    Angular
    Axial
    Each
    Includes
    Each
     
    Steel Hubs
    4 1/4"4 3/4"KeyedContinuous1 3/4"6454K1500000004,20020,2000.007"0.03"6454K250000000Two Buna-N Rubber Lubrication Seals, Two Steel Snap Rings6454K35000000
     

    Quick-Disconnect (QD) Bushings

    Image of Product. Front orientation. Pulley and Sprocket Bushings. Quick-Disconnect (QD) Bushings, Clamp-On Shaft Mount.
    Image of Attribute. Side1 orientation. Contains Annotated. Quick-Disconnect (QD) Bushings.

    Clamp-On Shaft Mount

    The screw connections on these bushings easily mate to compatible quick-disconnect sprockets and pulleys. Bushings fit quick-disconnect (QD) sprockets and pulleys of the same bushing trade number. As you tighten the included screws, the bushing grips the shaft and pulls it into the sprocket or pulley.
    Keyway
    Overall
    Wd.
    Wd.
    Dp.
    Fastener Tightening
    Torque, in·lbf
    Material
    Includes
    For Shaft
    Dia.
    Each
    Clamp-On Shaft Mount
     
    Bushing Trade Number SDS
    1 3/8"3/8"1/8"108Sintered SteelClamping Screws, Machine Key1 3/4"6086K326000000
     
    Bushing Trade Number SK
    1 15/16"3/8"3/16"180Sintered SteelClamping Screws1 3/4"6086K52700000
     

    Clamping Rigid Shaft Couplings

    Designed to grip evenly around your shaft, clamping couplings provide more holding power than set screw couplings without marring the shaft. Slide onto the end of your shaft and tighten the clamping screws to secure. Good for high-torque applications, rigid couplings connect two shafts that are aligned, allowing for no relative movement between the shafts.
    Steel
    Image of Product. Front orientation. Rigid Shaft Couplings. Clamping Rigid Shaft Couplings, For Keyed Shafts.
    Image of Product. Front orientation. Rigid Shaft Couplings. Clamping Rigid Shaft Couplings, For Round Shafts.

    For Keyed Shafts

    For Round Shafts

    For Shaft Dia.
    Overall
    Lg.
    OD
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    For Rotary Motion
    Each
    For Keyed Shafts
    1 3/4" × 1 3/4"4 1/2"3 1/8"4,00018,500Forward/Reverse, Start/Stop, Continuous61005K7990000000
     
    For Round Shafts
    1 3/4" × 1 3/4"4 1/2"3 1/8"4,00018,500Forward/Reverse, Start/Stop, Continuous61005K811000000
     
    303 Stainless Steel
    Image of Product. Front orientation. Rigid Shaft Couplings. Clamping Rigid Shaft Couplings, For Keyed Shafts.
    Image of Product. Front orientation. Rigid Shaft Couplings. Clamping Rigid Shaft Couplings, For Round Shafts.

    For Keyed Shafts

    For Round Shafts

    Stainless steel couplings have excellent corrosion resistance.
    For Shaft Dia.
    Overall
    Lg.
    OD
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    For Rotary Motion
    Each
    For Keyed Shafts
    1 3/4" × 1 3/4"4 1/2"3 1/8"4,0005,500Forward/Reverse, Start/Stop, Continuous61005K8220000000
     
    For Round Shafts
    1 3/4" × 1 3/4"4 1/2"3 1/8"4,0005,500Forward/Reverse, Start/Stop, Continuous61005K833000000
     

    Two-Piece Rigid Shaft Couplings

    Install and remove these shaft couplings without disconnecting the shafts, motors, and other attached components—they’re made in two pieces so you don’t need to slide them onto shaft ends. They’re also useful when you have limited access to the ends of the shafts. These couplings clamp onto the shafts, creating a secure hold that won’t mar them. Good for high-torque applications, they have a rigid construction. However, their rigidity means these couplings can only connect shafts that are well aligned.
    Black-Oxide Steel
    Image of Product. Front orientation. Rigid Shaft Couplings. Two-Piece Rigid Shaft Couplings , For Keyed Shafts.
    Image of Product. Front orientation. For Continuous Rotary Motion. Two-Piece Rigid Shaft Couplings , For Round Shafts.

    For Keyed

    Shafts

    For Round

    Shafts

    Steel couplings are stronger and handle higher torque loads than aluminum and stainless steel couplings.
    For Keyed Shafts—Couplings for keyed shafts have keyways that are cut to standard ANSI dimensions, so they fit snugly on ANSI keyed shafts to eliminate slipping during starts and stops.
    For Shaft Dia.
    Overall
    Lg.
    OD
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    For Rotary Motion
    Each
    For Keyed Shafts
    1 3/4" × 1 3/4"4 1/2"3 1/8"4,00018,500Forward/Reverse, Start/Stop, Continuous60845K9510000000
     
    For Round Shafts
    1 3/4" × 1 3/4"4 1/2"3 1/8"4,00018,500Forward/Reverse, Start/Stop, Continuous60845K961000000
     

    Machinable-Bore Clamping Rigid Shaft Couplings

    When one of your shafts is undersized from wear, oversized from coatings, or uncommonly sized, machine one end of these couplings to fit. They clamp around your shafts for a secure hold that won’t cause damage. But, you’ll need access to the end of each shaft to slide them into place. Since they’re rigid, they prevent movement between the shafts, making them good for high-torque applications. This also means your shafts must align to connect.
    Steel
    Image of Product. Front orientation. Rigid Shaft Couplings. Machinable-Bore Clamping Rigid Shaft Couplings.
    Image of Specification. For Keyed Shafts. Back orientation. Contains Inset, Border. For Keyed Shafts. Machinable-Bore Clamping Rigid Shaft Couplings.
    Image of Specification. For Round Shafts. Back orientation. Contains Inset, Border. For Round Shafts. Machinable-Bore Clamping Rigid Shaft Couplings.

    For Keyed

    Shafts

    For Round

    Shafts

    Steel couplings resist corrosion in dry environments.
    For Keyed Shafts—Couplings for keyed shafts grip the shaft’s key to eliminate slipping. They handle higher torque than couplings for round shafts.
    For Shaft Dia.
    Overall
    Lg.
    OD
    Max. Rotation
    Speed
    Max. Torque,
    in·lbf
    For Rotary Motion
    Each
    For Keyed Shafts
    1 3/4" × 0.485" to 1.750"4 1/2"3"Not Rated5,625Forward/Reverse, Start/Stop, Continuous3084K750000000
     
    For Round Shafts
    1 3/4" × 0.485" to 1.750"4 1/2"3"Not Rated4,220Forward/Reverse, Start/Stop, Continuous3084K51000000
     
    303 Stainless Steel
    Image of Product. Front orientation. Rigid Shaft Couplings. Machinable-Bore Clamping Rigid Shaft Couplings.
    Image of Specification. For Keyed Shafts. Back orientation. Contains Inset, Border. For Keyed Shafts. Machinable-Bore Clamping Rigid Shaft Couplings.
    Image of Specification. For Round Shafts. Back orientation. Contains Inset, Border. For Round Shafts. Machinable-Bore Clamping Rigid Shaft Couplings.

    For Keyed

    Shafts

    For Round

    Shafts

    303 stainless steel couplings resist rusting from water. But, they won’t stand up to salt water or chloride.
    For Shaft Dia.
    Overall
    Lg.
    OD
    Max. Rotation
    Speed
    Max. Torque,
    in·lbf
    For Rotary Motion
    Each
    For Round Shafts
    1 3/4" × 0.485" to 1.750"4 1/2"3"Not Rated2,900Forward/Reverse, Start/Stop, Continuous3084K630000000
     

    Two-Piece Rigid Shaft Coupling Bridges

    When your shafts are not close enough to use standard couplings, these have the length to bridge the gap. Install them anywhere on a shaft without removing components or having access to the ends of the shaft. Tighten the clamping screws to secure. Good for high-torque applications, rigid couplings connect two shafts that are aligned, allowing for no relative movement between the shafts.
    Cast Iron
    Image of Product. Front orientation. Rigid Shaft Couplings. Two-Piece Rigid Shaft Coupling Bridges .
    For Shaft
    Dia.
    Overall
    Lg.
    OD
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    For Rotary Motion
    Each
    For Keyed Shafts
    1 3/4"8 1/4"5 1/8"3,9655,500Forward/Reverse, Start/Stop, Continuous6417K230000000
     

    Shock-Absorbing Flexible Shaft Couplings

    Image of Product. Components of a Coupling Shown Assembled. Front orientation. Contains Annotated. Flexible Shaft Couplings. Shock-Absorbing Flexible Shaft Couplings.
    Image of Product. (Each Component Sold Separately). Front orientation. Contains Annotated. Flexible Shaft Couplings. Shock-Absorbing Flexible Shaft Couplings.

    Components of a

    Coupling Shown Assembled

    (Each Component Sold

    Separately)

    A strip of flexible spring steel wraps around the teeth of both hubs to absorb sharp, momentary load increases that can come from motor startups, emergency braking, or sudden impact with hard objects. When the shock load hits, the strip of spring steel (known as a grid) flexes to spread out the load. After the load passes, the grid straightens back out. They're commonly found in wire drawing and cutting machines, pulverizers, and mixers. Compared to spider couplings, jaw couplings, and other flexible shaft couplings, these handle higher torque while taking up less space. All have keyed bores to work with keyed shafts, which transmit higher torque with less slippage than round shafts.
    A complete coupling consists of two hubs as well as a grid and cover assembly (all sold separately). The grid and cover assembly includes a spring steel grid, aluminum cover, rubber seals, and grease for lubrication. When ordering, please choose components that have the same manufacturer series number, otherwise the grid will not fit.
    Hubs
    Grid and Cover Assemblies
    Replacement
    Grids
    Replacement
    Seals
    Misalignment Capability
    Overall
    Lg.
    OD
    For Rotary Motion
    Manufacturer
    Series
    For Shaft
    Dia.
    Each
    Parallel
    Angular
    Max. Rotation
    Speed, rpm
    Max. Torque,
    in·lbf
    Each
    Each
    Each
    Black-Oxide Steel
     
    For Keyed Shafts
    4 7/8"3 19/32"Continuous, Forward/Reverse, Start/StopMartin (1050T)1 3/4"3395N400000000.016"0.25°4,5003,8503395N12300000003395N11400000003395N132000000
     
    Grease
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