Bergen Pipe Supports’ constant spring hanger incorporates a design that generates a constant supporting force throughout its total travel range. The design, using a compression spring, a lever, and a spring tension rod, creates a moment counterbalancing about the main pivot pin. This concept utilizes the principle of a varying leverage about a main pivot that compensates for the varying spring force as the lever travels from the high to the low point or from the low to the high point. Constant spring hangers are used on systems where there are large vertical thermal movements, critical stress conditions, or a combination ofboth. Constant spring hangers are also used at locations to avoid transfer of load from support to support, or to connecting equipment, such as, boiler nozzle or ductwork connections.
All spring units are designed to meet the requirements of:
- ASME Code for Pressure Piping, ASME B31.1, B31.3
- Manufacturers Standardization Society (MSS), SP-58,and SP-69
- Federal Specification WW-H-171E and A-A-1192A
- Manufactured in an ISO 9001:2015 Certified Facility
standard design features
- The geometric design provides constancy of support effort throughout the full range of travel and load adjustment. The design provides a compact and more versatile unit.
- Provides a wide range of load and travel capacities *
- Each constant is individually calibrated at the factory to match the specified load, and pre-set to the Cold load setting before shipment.
- A minimum of 10% plus or minus of load adjustment from the specified load is provided
- White arrows marked “С” indicates cold setting of constant; Red arrows marked “H” indicates the hot or operating condition
- Field load adjustment is made by turning the single load adjustment bolt Heavy gauge spring cover provides protection and good appearance
- Load Rod swings at least 4 degrees in all directions from vertical
- Non-resonant to all vertical Vibrations
- Stainless steel nameplate
- Standard shop primer paint with hot dip galvanized and special paint finishes available.
Constant supports are made in two basic designs, the 880V (vertical design) and the 881H (horizontal design). Both the figure No. 880V and 881H are available to accommodate total travels from 1 1/2 ” to 20″ and loads from 27# to 87,500#.
The 881H – Type U Upthrust will accomodate total travels from 1 l/ ” to 12″ and loads from 30# to 27,195#.
View our catalog for the full range of constant spring supports.
TRAVELSTOPS AND HYDROSTOPS
Bergen Pipe Supports Constant hangers are equipped with built—in upper and lower stops to prevent excessive travel beyond the specified range. A 10 position Hydrostop is also provided, painted red, that is used for hydrostatic testing, and presetting to the Cold load.
The Hydrostops are capable of supporting test loads equal to two times operating loads. An instruction tag marked “ATTENTION” contains removal and, storage instructions of the Hydrostop and is attached to the spring cover.
choosing your constant spring support
Size Selection– On pages 95 to 102 of the Bergen 17 Catalog is a chart is given to guide in choosing the proper size hanger. Before using the chart, two things must be established. (a) Determine actual travel that the constant will be supporting. (b) Determine the total load that the hanger will be supporting. (Include installation and associated hardware below the constant).
After determining actual travel, determine the total travel by calculating actual travel plus your required overtravel, usually 20% of the actual travel . The percentage of overtravel is usually never less than 1 inch. For example, actual travel of 1 inch, the total travel will be 2 inches. For 7 inches of actual travel, total travel will be 8 l/2 inches.
After determining the total travel, go to the chart and find the column that has the total travel needed. Next, go down the column until the load needed to be supported is equal to or greater than the load shown. The corresponding size will be the size required.
For example: 4 inches of total travel and 2750 pounds will be a size 34 according to the selection charts. You can find the selection charts as a standalone document here.
After determining the size , the next step is selecting the style of hanger that will work the best for the site requirement, which can be either a vertical 880V series, horizontal 881H series unit.
After determining the style, a decision must be made as to the type of hanger which best suits space and structural requirements.
The standard upper attachment types are depicted in the graphic below. Note that the Type A, D, E, and G units are the Fig. 880V, and Type B and C are the Fig. 881H units. See the catalog for a depiction of each unit and type in its standard configuration.
Note: Types A, B, C, D, and E are available in 880V and 881H series. Types F and G are available in 880V series only. Type U is available in 881H only.
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