FAQ

Q: I have an application for a caster that none of your standard products will work for. Can you still assist with my needs?

A: Absolutely, RWM Casters prides itself on solving application specific problems with creative and intuitive designs. Our engineers are ready to tackle any and all of your caster and nonpowered material handling needs. Please contact our customer service representatives at 800-634-7704 to get things rolling!

Q: What is meant by the term Swivel Lead and how is it determined?

A: The “Swivel Lead” of a caster is the distance from the vertical centerline of the swivel section or raceway to the centerline of the wheel. Please contact customer service for additional guidance when it comes to choosing the optimum swivel lead to suit your specific application.

Q: What is a swivel radius?

A: A swivel radius is a measurement taken from the vertical centerline of the swivel section or raceway to the outermost component and is used to determine the amount of space necessary for a caster to swivel 360 degrees.

Q: What conditions are the casters in the catalog rated to handle?

A: Catalog items are rated with manual operation in mind. Temperature tolerances can vary from product to product and are noted on each page. For speeds over 3 mph and for high-temperature applications please contact RWM for guidance on selecting the right caster or wheel to meet your needs.

Q: Why are the mounting holes of some top plates slotted?

A: Some top plates use a slot in order to accommodate various mounting bolt patterns. This enables the rig to be mounted to several hole patterns and be adjusted if necessary.

Q: How fast can a caster or wheel be towed?

A: Towing speed can have a great effect on which caster or wheel product is right for you. Towing applications can be prone to heat buildup and pre-mature wheel failure. You’ll notice some of our wheels and casters have been noted for towing applications and may have received ratings for different speeds such as 3, 6 or 10mph. These make excellent choices when towing. For specific capacities and application information please contact RWM’s customer service staff at 800-634-7704.

Q: I have rough floors - What wheels would you recommend?

A: Rough floors can be addressed in multiple ways. The larger the diameter wheel, the easier it will traverse over rough surfaces. When larger diameters aren’t feasible different materials such as rubber and polyurethane should be considered as options. RWM uses premium PTMEG urethanes and has the knowledge necessary to ensure your products keep rolling safely. Please contact customer service to get things moving smoothly!

Q: What is the best bearing for my application?

A: Choosing what bearings to use is an important decision. Whether you want a wheel that is to be towed, one that is easy to roll, or one that might not ever have to roll should be taken into consideration. View the RWM Bearing Selection Guide. Please contact our friendly customer service staff to get things rolling the right direction.

Glossary of Terms

Listed and defined below are common terms used to describe and specify casters and wheels. This information is offered for your convenience.

  • Brinelling – A permanent deformation of a ball raceway that resembles dimples, caused by the ball bearings during severe loading or severe impact.
  • Cold Forging – A process in which extremely heavy presses are used to form the integral parts of a swivel section the top plate, yoke, and bottom. Cold forging not only provides silk smooth raceways, it also improves the strength of the swivel section work hardening the steel to change and yield greater mass resistance at stress points.
  • Durometer – Scale for measuring the hardness of a wheel material.
  • Hot Forging – A process in which extremely heavy duty presses/hammers are used to shape heated billets of steel. This process allows steel to be formed to various shapes and thicknesses within the same part to aid in handling stress points.
  • Kingpin – A rivet or threaded stud or bolt with nut which integrally holds the mounting plate and horn assembly of a swivel caster together. The size and type of the kingpin is one of the most important components in caster selection and loading.
  • Kingpinless™ – A patented swivel section which is held together without a rivet or nut and bolt kingpin. Kingpinless™ swivel sections are held together by a single row of ball bearings which are contained by a full contact interlocking swivel raceway design.
  • Load Capacity – The load a caster wheel will hold.
  • Main Load Bearing – The row of steel balls or rollers that swivels the horn base in relation to the mounting plate of a swivel caster and must be properly sized to counteract the direct or radial thrust load.
  • Mounting Plate – The flat base (usually with four bolt holes) that forms the top of the caster and permits attachment by bolting or welding to a flat surface.
  • Overall Height – The total vertical distance from the floor to the top of the mounting plate, or the base of the stem of the caster.
  • Raceway – A channel that consists of one or two rows of ball bearings or rollers, which allows a caster to swivel.
  • Radial Thrust – The downward forces exerted on the caster by the load and loading. This force is counteracted by the main load bearing.
  • Retaining Washer – A washer pressed into the hub ends to retain the bearings. A sealed version of this washer keeps grease in and debris out of the bearings.
  • Rig – A caster without a wheel and axle.
  • Rollability – The ease of starting and maintaining rolling motion. Rollability is determined by many factors like, durometer of the wheel, floor conditions and surfaces, load, and size of wheel bearings.
  • Side Thrust – Side forces exerted on a swivel caster and properly counteracted by the secondary load bearing.
  • Spanner Bushing – A non-rotating sleeve of hardened seamless steel tubing that fits over the axle in roller bearing caster wheels. It serves a dual purpose of providing a smooth inner raceway for the wheel roller bearing and strengthening the caster by permitting the legs to be tightened against it.
  • Swivel Caster – a swivel caster incorporates an additional swivel joint above the fork that allows the fork to freely rotate about 360° allowing the wheel to roll in any direction. This makes movement possible any direction without changing orientation.
  • Swivel Lead – The distance between the centerline of the kingpin and the centerline of the axle of a swivel caster. The larger the offset, the easier swiveling, but the smaller offset offers greater strength.
  • Swivel Radius – The horizontal distance from the center of the Kingpin to the edge of the tread of the wheel.
  • Thrust Washer – A steel washer between the hub ends of the wheel and the inside of the caster legs.
  • Tread Width – Width of the wheel tread.
  • Wheel Diameter – The distance of the wheel measured vertically from one side of the tread to the other.
  • Yoke – The caster part, which comprises legs, plus a base (horn base for swivel caster or mounting plate for rigid).