Variable Spring Units
Quality Pipe Supports Variable Spring Units are devices used to support pipework which is subject to moderate vertical displacement due to temperature changes or subsidence.
- Units comprise a pre-compressed spring coil in a cylindrical casing with a load and travel indicator.
- Individual calibration of the specified load is undertaken by electronic load-travel recorder.
- Stainless Steel scale plates are provided showing all the individual support details.
- Standard units are manufactured from carbon steel, but we regularly manufacture units from Stainless Steel.
- Hot Dip Galvanising and multi-coat paint systems are available.
Design PrincipleIt is recommended that a variable spring support unit only be used when the load variation is less than 25% from the pre-set to operating load and displacements up to around 70 mm. Where the variability is more that 25% then a constant spring support should be considered. Practical and technical advice is available from us at any time.
ConstructionAll units are pre-set to their cold load. Each unit is checked through the total working range and tested on a specialised test rig which is calibrated to national standards.
The variable spring support finish is available as follows:
- Hammer finish paint
- Hot dip galvanised
- Customer specific paint finish.
- Multi Coat paint finishes
The helical Spring coils are plastic coated, and the actual units are produced in high quality carbon steel; we also offer units manufactured from austenitic stainless steel and various alloy steels where required.
Where a spring unit is required which is not covered by the QPS range, our technical department will design a unit for your particular requirement. All QPS variable spring support units are capable of supporting pipework that is subject to hydrostatic test loads up to twice the operating load.
Model RangeThe QPS standard range of Variable Spring Supports are produced in four basic travel ranges , 35mm, 70mm, 140mm, ad 210mm, and these travels stated represent the maximum working range of the spring units. – These are referenced QV1, QV2, QV3, and QV4 respectively. We recommend that the actual pipe load is correctly supported when the pipe is in its standard working position.
When ordering please specify:
- QV. number, e.g. (QV2)
- Model type, e.g. (A, B, D etc.)
- Model Size (a wide range is available from size 0-22)
- Thread details
- Vertical movement and direction of movement, e.g. cold to hot, 16 mm up
- Preset load (we can calculate this for you if fequired)
- If Hydrostatic stops are required
- Protective finish
- Marking (identification) number
- Distance between rod centres and total load for model "G".