VARIABLE SPRING SUPPORTS • Type C – Also designed for limited headroom applications. The unit has two lugs welded to the top of the casing to permit connecting with a bolt or pin through a single lug attachment to the structure. • Type D – Designed for use where the variable spring is positioned above the supporting structure and spring adjustment is made from the top. • Type E – Also designed for use where the variable spring is positioned above the supporting structure, but where the spring adjustment must be below the structure on which the case is supported. • Type F – Designed to support piping from below. Used to support pipe from the floor or where support from overhead is not practical. • Type G – For use where headroom is limited or an obstruction prohibits the use of a single rod type Variable Spring.
LOAD PRESET BAR AND TRAVEL STOP The Load Preset Bars are installed at the factory at the Cold Load setting of the unit. The Travel Stops, which are optional and will be provided only if ordered, include both the Load Preset Bars to preset the unit at the Cold Load setting and more importantly a down limit stop which locks the unit at that position. This locking effect results in the unit functioning as a rigid hanger during erection, hydrostatic testing, chemical cleaning or other condition which may cause the unit to exceed its load rating. The Travel Stops are designed for twice the maximum working load of the unit and are installed at the factory with a “Caution” tag which calls attention to the fact that they must be removed before system startup.
INSTALLATION AND ADJUSTMENT In following these installation instructions note that the adjustment is accomplished by rotating the turnbuckle, rod coupling or load column provided with the spring unit. Firmly secure the spring unit to the structure. Attach the appropriate rod and/or pipe attachment. Cut the banding holding the Load Presets or Travel Stops. Remove the
down limit stops, if applicable. To remove the Load Presets, the spring load must be increased slightly by use of the adjustment means provided. After the Load Presets or Travel Stops have been removed, readjust the spring unit back to the exact Cold Load setting. Prior to startup, be sure all of the spring units have had their Load Presets or Travel Stops removed, and have been adjusted to their Cold Load setting. After startup and when the piping system has stabilized thermally, the Load Indicator on the unit should be at the Hot Load (Operating) setting. If it is not, the spring should be adjusted to the Hot Load setting. No further adjustment should be needed.
ORDERING INSTRUCTIONS: When ordering a Variable Spring Support please specify for each unit: 1. Travel Series: 910, 920, 940, 960, or 980 2. Spring Type: A, B, C, D, E, F or G 3. Spring Size: 0 through 22 for all Travel Series; 000 and 00 available for Travel Series 920 only 4. Movement and Direction of movement from the Cold (Installed) position to the Hot (Operating) position. 5. Hot Load (Operating position). 6. Cold Load (Installed position). 7. Rod Spacing: For Type G only, specify center to center rod dimension 8. Customer hanger identification or Mark Number (if any). 9. Finish: Primer Painted, Galvanized, Epoxy Painted, Stainless Steel, or Special Customer Requirements. 10. Type B and C units do not come with connection pins to the structure. If required, please order as a Figure 291 and specify pin size and finish. 11. Specify if unit requires Travel Stops, Lifting Lugs, Limit Stop Load Column Guide, Adjustable Travel Stops or any other special feature desired.
TYPICAL APPLICATIONS OF VARIABLE SPRING SUPPORTS
EXISTING STEEL
TYPE A
TYPE B
TYPE C
TYPE D
TYPE E
TYPE F
TYPE G
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