What is a Rail Clamp?

The term rail clamp applies to a large range of products designed to support, guide, join, or provide a decorative finish to hand rails, train tracks, and cable guide rails. Rail clamps are typically designed with an internal profile which mirrors the external profile of the rail system on which they are used. They may be of a slip on, one piece, or a two piece, clamshell design and made of light gauge or heavy materials depending on their use. Rail clamps used in industrial rail applications are usually plain and utilitarian while those used in domestic, architectural, or marine environments typically feature attractive designs and decorative finishes.

Rail clamps are used as supports, guides, and finishings on a number of railing systems in various applications. A rail clamp is generally formed with an internal profile which mimics the shape of the rail it is designed to clamp or support. Depending on the degree of design force involved, these clamps may be manufactured from light gauge materials or from strong cast, forged, or machined steel. The type of clamping and locking mechanisms also depend on the forces involved. These can range from one or two simple self-tapping type screws to multiple rows of heavy gauge bolts.

The overall design of a rail clamp will typically be dictated by the shape of the rail and the degree of visual appeal that is called for. For instance, rail clamps intended for locking train tracks in place are manufactured from cast or forged steel and locked in place on the track member and cross ties by large bolts or spikes. The internal profile of these clamps is a mirror of the cross section of the track member. Rail clamps used to support or finish round hand rails usually are of a two-part, clamshell design or consist of a spherical member with a hole in the center through which the rail is passed. These clamps will also be fitted with a locking plate or lug which is used to attach the clamp to a support.

A rail clamp intended for square rails, such as those used as runners for festoon cables on overhead cranes, are also often of a half shell design. In these applications, the rail clamp will lock onto the back of the rail only to allow the unimpeded travel of the cable runners. Square rail clamps may also be simple L-profile plates with a single locking bolt on either end. Most rail designs also have finishing clamps specifically designed for them. These are generally used at the end of a length of rail and are typically closed on one end.

The design, finish, and embellishment of a rail clamp also depends largely on environmental and aesthetic considerations. A rail clamp designed to support a hand rail on a luxury yacht or a penthouse balcony is likely to be stylishly designed and feature a polished or brushed finish or decorative plating. A rail clamp used for a similar hand rail on an off-shore oil rig is likely to be very plain and functional and feature a utilitarian, corrosion-resistant finish. Rail clamps are also manufactured from high-impact plastics, wood, and composites for use with rails of like materials. Temporary clamps may also be of a quick release design and lock onto the rail using a swing out bolt and wing nut arrangement.