Wire rope suspension is increasingly being used for mounting building services components in commercial, public sector and industrial buildings. There are major advantages of flexible positioning and installation productivity benefits compared to traditional system.
Building services – both in terms of plant items and distribution systems such as pipework, ductwork and cabling – are currently positioned within buildings using a range of methods and materials. The majority of services are suspended from above using support systems comprising three major components; the fixing which is attached to the building structure, the suspension element itself, (the length of which can be adjusted to position the service at the right height), and the attachment or sling that is attached to or around the service.
Traditionally the suspension element has been a rigid component, usually threaded rod. While this is usually in tension, it also provides some resistance to compressive forces, helping to ensure the rigidity of an installation. Wire rope suspension elements are only strong when under tension and provide no resistance to compressive or bending loads, although careful design (for example setting wires at angles) can usually provide suitable restraint. In addition, most threaded rod systems (fixings, threaded rod and associated fittings) are significantly over specified for most applications, allowing considerable freedom of installation methods. Wire rope systems tend to be more closely specified against the design load and could be overstressed if incorrectly installed. However the time taken for installation is dramatically reduced compared to that for threaded rods, significantly reducing installation costs. The other significant difference is that where threaded rods are usually mounted vertically, wire rope systems can easily be installed at an angle. This significantly increases the range of suspension points that can be used.
SCOPE OF WIRE ROPE SUSPENSION:
Wire rope suspension can be used to support a very wide range of loads and objects. This publication deals with applications within the following criteria:
• Internal or semi-internal applications (not external)
• Metal wire rope suspension (not rods or plastic ropes)
• Moderate loadings (up to 1 tonne working load per suspension point)
• Static fixed length permanent or semi-permanent suspension (no lifting).
Almost any piece of building services equipment could be suspended using wire ropes, such as:
• Fan coils and air handling units
• Radiant heating and cooling emitters (radiant tubes, radiant panels, chilled beams)
• Cable trays
• ceiling grids
• Luminaires and lighting systems