What happens if variable spring variability increases?

What position should a variable spring be adjusted to before the pipeline is put back into service after a shutdown?

February 1, 2011

Thevariable spring should be restored to its original installed (cold) position.

Variable Spring with White Diamond Indicating Cold Position
Variable Spring with White Diamond Indicating Cold Position


What are spring support jacking bolts?

A spring support jacking bolt is a variable spring accessory that aids inremoving the upper limit travel stops. They are usually used in applicationswhere large installed loads are present. They are located directly above theupper travel stop. By tightening the jacking bolt, the installed load can bemore easily transferred to the spring load column.


F-Type Variable with Jacking Bolts
F-Type Variable with Jacking Bolts

What are the sizes of spring supports?

November 2, 2010

For variable springs there are 23 sizes with loads ranging from 50 lb. through 50,000 lb. For constant springs, there are 110 sizes with travel ranging from 1″ to 14″ and loads ranging from 0 lb. to 90,000 lb.

F-Type Variable Springs for a Local Chemical Plant

F-Type Variable Spring Supports

24,500 lb. Load PTP- 8 Type C Variable Spring Assemblies
PTP-8 Type C Variable Spring Assemblies

Figure 100 C-Type Constant Springs


PTP 100-C Size 84 Constant

How do you read the load indicator on a spring support?

To read the load indicator on a variable spring support, you need to read the measurement aligned with the bottom of the spring load indicator.

Load Indicator on a Variable Spring

How much weight can a spring support?

The maximum load that a standard variable spring can support is 50,000 lbs. The maximum load that a standard constant spring can support is 90,000 lbs. A big ton spring support can be be used for loads greater than these standards.

Constant Spring Designed for a 35, 144 lb. Load
Constant Spring Designed for a 35, 144 lb. Load

How do I check the load setting of a spring support?

To check the load setting, examine the position of the bottom of the load indicator with respect to the scale on the spring's tag. Read from the bottom of the load indicator to determine position. Next, look at the size of the spring located on the tag. Then, refer to the appropriate load and travel table (Constant Load & Travel Table or Variable Load and Travel Table) to determine the respective spring rate and the “0” load (minimum working range load). Multiply the spring rate by the position value and add that to the “0” load value.

What is the maximum load variability of a variable spring hanger?

Per the MSS standards, the maximum recommended variability for a variable spring hanger is 25%. If required, you can specify a variability less than 25%.

Variable Spring and Cro-Moly 3-bolt Clamp Assemblies for a Power Generation Facility
Variable Spring and Cro-Moly 3-bolt Clamp

What does travel mean when discussing spring supports?

When dealing with variable spring supports, travel refers tothe amount of deflection from our installed position to our operating position.When dealing with constant springs, travel refers to the total amount ofdeflection, which could be accommodated by the support.

Spring Support Travel

What are spring cans?

Spring can” is the general term used to describe either variable or constant spring supports.

Custom Spring Can with Slide Plates
Custom Spring Can with Slide Plates


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