Issue 8 -2005.
Gripple
(Guide) Standard Specification
Introduction
Gripple hangers can be used to suspend all static Mechanical, Electrical and HVAC services. Gripple hangers consist of a pre-formed wire rope sling with either a pre-formed ferruled loop, permanently fixed threaded stud, or permanently fixed end-stop with or with out a toggle. This is secured and tensioned with a Gripple.
Standards
Gripple hangers have been independently tested by Lloyds Register, APAVE, SMACNA, UL, TÜV and Radco and complies with the requirements of DW/144. The wire rope used is manufactured to BS 302 (1987). Gripple Ltd is an ISO 9002 approved company.
All Installations shall comply with BSRIA Code of Practice 22/2002
Product Selection
The contractor shall select the correct specification of Gripple hangers for supporting each particular service from the table below. Each size is designated with a maximum Safe Working Load (which incorporates a 5:1 safety factor).
The correct specification of Gripple hangers required is determined using the following formula:
Weight of object suspended per metre (kg) x Distance between suspension points (m)
= Weight loading per Gripple hanger suspension point (kg)
Where the installed wire rope is not vertical, then the working load Limit shall be reduced in accordance with the recommendations given in the manufacturers handbook.
No external release mechanisms shall be used on the locking device.
The contractor shall select the correct length of wire rope required to support the service. Lengths from 1m upwards are available in half metre increments. Consideration shall be given to all aspects of overloading and underloading. If in any doubt, please refer to the manufacturer guidelines and advice.
Gripple Hanger Safe Working Loads
Size
/ Safe Working Load (kg)No.1
/ 0-10 (0-22lbs)No.2
/ 10-45 (22 – 100lbs)No.3
/ 45-90 (100 – 200lbs)No.4
/ 90-225 (200-495lbs)No.5
/ 225-325 (495 – 715lbs)Installation
The Gripple hanger suspensions can be fixed to an existing building structure by an approved method:
- Gripple Loop-Fast can be wrapped around purlins, beams, roof trusses and other accessible building features.
- Gripple Stud-Fast can be fixed, with suitable anchors, into concrete ceilings and structures, metal decking and pressed metal brackets (using nuts).
- Gripple Toggle-Fast can be fixed into profile roof cladding, light fittings and luminaries.
When using Gripple hangers with other manufacturers’ fixings these must be installed in accordance with the manufacturer’s loading and installation instructions.
The free end of the wire rope should be threaded through one channel of the Gripple before being either passed around the object being suspended, or connected to it, using a suitable fixing. The wire rope is then threaded back through the second channel in the Gripple. It is recommended that objects be installed low and adjusted upwards to the required level.
Should the object require lowering, the Gripple can be unlocked using a setting key allowing the suspension to be lowered. When unlocking the Gripple, the weight of the suspended object must be independently supported.
The wire rope must not be damaged, twisted or deformed in any way prior to, or during, installation. Any such ropes must be discarded and replaced.
Only wire rope supplied by the manufacturer shall be used. Any use of non-approved wire rope shall void all warranties.
Lubricants, paint or any other coating should not be applied to the Gripple hanger as it may impair its performance.
Installation shall conform to BSRIA code of Practice 22/2002.
Gripple hangers should always be installed in accordance with all the manufacturer’s recommendations.
The system to be used shall be supplied in a complete kit form supplied by the same manufacturer.
The kit supplied shall be fully warranted by the manufacturer.
The Gripple supplied shall be a two (2) channel self-locking device which automatically locks when fully weight loaded.
The release system shall be separate to the housing and must incorporate a stand-alone release mechanism, making it inaccessible to tampering.
The Gripple locking device shall be a one piece housing, fully tested and approved by the manufacturer for the wire rope supplied.
Users of the wire rope suspension system shall be fully conversant with the approved manufacturer’s installation techniques.
Electrical Installations
Gripple wire rope systems can be used for supporting ladder, tray and basket. The wire rope can be attached directly to the containment, but only with approval from the Project Consultant.
Where containment is supported, care must be taken on the selection of the correct wire rope taking into consideration the type and number of cables to be installed.
Busbar/lighting: Where wire rope supports are used for these types of systems, consideration should be given to the aspects of underloading and overloading.
HVAC Installations
Gripple wire rope supports may be used on most types of ductwork, the more common being rectangular, oval, round and spiral.
Where a cradle support method is used on rectangular ductwork, then it is recommended that corner saddles be used.
On circular, spiral or oval ductwork, the wire rope may be used either in the cradle method or a wrap around system.
Consideration must be given on weight loading and underloading.
Mechanical Installation
The Gripple wire rope system may be used to support pipe work. The preferred method is either using a trapeze bearer or using a pipe fixing bracket.
For installation of water pipes consideration should be given to the fully loaded weight when selecting the Gripple hanger size (see Manufacturer’s Calculation Chart).
This same will apply to Radiant Panels, Chilled beams etc.
Roger Aisladie
UK Technical Manager
Mobile: 0797-953-6059
Gripple Ltd
The Old West Gun Works
Savile Street East
Sheffield
S4 7UQ
Tel. 0114 228 8688
Fax. 0114 275 1155