Dodge Sidewinder Elastomeric Wrap Coupling, 5R-80R

Elastomeric wrap coupling with a reinforced shear plane

The Dodge Sidewinder is a jaw-in-shear wrap coupling: two hubs, a one-piece elastomer element that wraps around them, and a cover held by cap screws. In a wrap coupling the torque passes through the shear plane of the element, which is also where such couplings usually fail, so Dodge reinforces that plane with its patent-pending CoreStrike technology. The element absorbs misalignment, shock and vibration so that those forces are not passed on to the connected machines, and the cover and hubs carry e-coating against corrosion. Dodge reports 2.5 times longer average life than the nearest competitor in accelerated testing run at 150 percent of catalogue torque, with 1 degree angular and 0.04 or 0.08 inch parallel misalignment.

Sizes 5R to 80R are manufactured in the USA, with clearance-fit hubs on 5R to 50R and interference-fit hubs on 60R to 80R. Nylon-patched cap screws keep the cover from loosening under vibration, and the set screws sit at 65 degrees for shaft holding power.

Technical specifications

Ratings by size

Interchange, chemical compatibility and ordering

Dodge states that Sidewinder elements and hubs are part-for-part interchangeable with Falk Wrapflex, so a worn element can be replaced alone while the hubs stay in service; the interchange table lists element part numbers 003960 to 003968 for sizes 5R to 80R. Falk and Wrapflex are trademarks of their owners and are used only to identify those products. The flyer gives a chemical compatibility chart for the element on a 1-to-3 scale: mineral oil, silicone oil, alcohols and vinegar rate 1 (minor effect), diesel oil, fuel oil and salt water rate 2 (moderate), and gasoline, kerosene, benzene and sulfuric acid rate 3 (severe).

Part numbers cover rough-stock-bore and finished-bore hubs in inch and metric sizes, elements, and cover and element assemblies in steel or nylon. A service factor table lists values for applications from agitators to textile mills, for example 1.00 for centrifugal pumps and fans and 2.50 for gyratory crushers. Confirm before ordering: torque with the service factor, bore and keyway, operating temperature and fluids near the element.

Sizing a Sidewinder coupling for the drive

Calculate design torque from the motor power and the speed at the coupling, then multiply by the service factor from the Dodge table for the driven machine. Choose the smallest size whose rated torque covers that figure and whose maximum speed is above the running speed. Finally, check that both shaft diameters fall inside the bore range of the chosen size; if one shaft is too large, step up a size rather than pushing the bore limit.

Note whether the application starts frequently, reverses, or sees shock loads from crushers, reciprocating compressors or conveyors carrying lumpy material, since these push the service factor upward. Also consider the space available around the coupling for installation and for replacing the element later without moving the motor or gearbox.

Installation and alignment

Clean shafts and bores, check keys for a proper fit, and mount the hubs following the clearance-fit or interference-fit practice for the size. Set the gap between hub faces to the value in the ratings table, then tighten the set screws. Wrap the element around the hubs and fit the cover, tightening the cap screws evenly to the torque given in the Dodge installation instructions.

Although the element tolerates misalignment, precise alignment at installation leaves margin for thermal growth and foundation settlement over time. Use a dial indicator or laser alignment system to bring parallel and angular values well inside the published limits, recheck after tightening the machine hold-down bolts, and record the final readings for future reference.

Operating conditions in Oman and the GCC

Pump stations, water treatment plants, cement works and mining sites across Oman often run couplings in hot, dusty and sometimes humid surroundings. The element's published temperature range covers typical ambient conditions, but the temperature inside a closed guard on a sun-exposed skid, or next to a hot pump casing, can be considerably higher than air temperature, so check it during commissioning. Ventilated guards and shading help keep the element within limits.

Use the chemical compatibility chart when the coupling sits near diesel engines, fuel transfer pumps or seawater intakes, because splashes or drips of these fluids can shorten element life. Protect the coupling from direct spray where possible and clean off any contamination during routine checks.

Routine inspection

With the machine safely isolated, look through or remove the guard and inspect the element for cracks, tears, hardening or fine rubber dust around the coupling, which signals wear or misalignment. Confirm that cover cap screws and hub set screws remain tight. Because elements are replaced without moving the hubs, keeping a spare element for critical drives allows a short stop instead of a prolonged outage.

Documents and quotation

The attached PDF is the Dodge Sidewinder wrap coupling flyer with dimensions, ratings and part numbers. Related drive items are listed under Electric Motors and Gear Units. Send the machines, torque, speed and shaft sizes for a quotation.