RL

See ‘ordinary lay’

RSJ

Rolled steel joist.

RADIUS

The distance between the centre of a circle and its outside edge.

REEVE

To thread rope through lifting gear such as sheaves or put one eye through the other for slinging.

REEVE FACTOR

The factor by which the WLL of a sling is adjusted to give its SWL for a particular manner in which the sling is reeved.

REGULAR LAY

See ‘ordinary lay’

REMOTE-RELEASE SHACKLE

A purpose designed shackle with an operating rope enabling it to be disconnected by a person standing below the lifting point. Often used to lift columns during steel erection.

RIGGING

The use of mechanical load shifting equipment and associated gear to move, place or secure a load including plant, equipment or members of a building or structure and to ensure the stability of those members, and for the setting up and dismantling of cranes and hoists, other than the setting up of a crane or hoist which only requires the positioning of integral outriggers or stabilisers

RIGGING SCREW

An enclosed device with an anchorage point and a threaded rod in each end. Used to tension an FSWR or to provide fine adjustment to a sling assembly.

RIGHT HAND LAY

A method of rope construction where the strands are laid up in a clockwise direction. Sometimes called a ‘Z twist’ because the strands run in the same direction as the central part of the letter Z.

ROOF RIG

See ‘suspension rig’.

ROOSTER SHEAVE

The head sheave for the auxiliary winch on the top of the boom head of a hydraulic boom crane.

ROUGH TERRAIN CRANE

A mobile crane designed to operate on unimproved natural terrain and disturbed terrain of construction sites.

ROUND SLING

An endless synthetic fibre sling constructed with a circular cross-section.

RUNNING GEAR

Flexible ropes which run over sheaves or drums and the gear used with such ropes.

ROLLED STEEL JOIST

A structural steel member with an I-section, now largely superceded by universal beams (UB’s) and universal columns (UC’s).