Red, White and Blue Marks:
All constants are shipped with at least 3 color-coded rivets (red, white and blue).
Red: operating (HOT) position
White: installation (COLD) position
Blue: over travel (MAX AVAILABLE) position
Below are sketches of one direction vertical travel:
Below is a sketch of dual direction vertical travel:
| Type: | B-Type Constant Spring Supports |
| Size: | 11-5/8 W x 41” L x 19” H to 21” W x 88” L x 38” H |
| Material: | A36 Carbon Steel | Hot-dipped Galvanized |
| Design: | Operating Load Range: 3,170 lb. to 48,400 lb. Movement of 3” to 8” |
| Testing: | Q.C. Inspection | Load and Travel Tests |
PT&P manufactured B-type constant spring supports for LNG service in Louisiana. These constants are fabricated from A36 carbon steel with alloy steel 5160 spring coils. The constants are designed for an operating load range of 3,170 lb. to 48,400 lb., and movements from 3” to 8”. They range in size from 11-5/8 W x 41” L x 19” H to 21” W x 88” L x 38” H. To avoid delivery delay, a standard frame was paired with an oversized coil and coil housing. The lugs were rotated 90 degrees from the standard to allow the hanger to swing beyond +/- 4” of side-to-side swing. Standard load and travel tests were performed prior to shipment.
See PT&P’s performance testing of our Nano Constant
| Type: | Constant Spring Supports |
| Size: | 14″ x 19″ x 64″ |
| Material: | A36 Carbon Steel |
| Design: | 2 1/2” to 5” Total Travel and 7,681 lb. Load |
| Testing: | Standard Load and Travel Tests |
PT&P custom designed and manufactured C-Type constant spring supports for a chemical plant in Italy. The constants were designed for travel from 2 1/2” to 5” and are specified to carry a load of 7,681 lb. They are fabricated from A36 carbon steel and have a physical size of 14″ x 19″ x 64″. The supports were designed for max deviation of 6%. The standard load adjustment is 10%. However, this unit was designed with capability of up to 20%, while the standard load deviation is 4%. This constant was custom designed to allow for single pin connection with negligible constant frame at the pin connection. A multi-position locking device was installed, and standard load and travel tests were performed to ensure quality and precise performance.
PT&P designed U-Type constant spring supports for an LNG plant in Canada. These are horizontal constants designed to support piping from below where the base plate is bolted directly to the top of the steel or the foundation using anchor bolts. These specific constant springs are designed to support an operating load of 67,420 lb. with 6” of total upwards travel. The constants are fabricated from galvanized carbon steel for protection against corrosion. Standard load and travel testing were completed to ensure the quality and performance of these constants.
This PTP-100 Type-G constant spring support is 96″ long by 40″ high and will support a 12,818 lb. load. It has an actual travel of 0.3″ and total travel of 1-1/2″. The G-type constant is comprised of two standard constant spring housing sub-assemblies joined together with an intermediate bridge assembly. The bridge assembly is customized to handle up to 26,000 lb. of hydro load. The G-type assembly allows for use in applications with limited space. Special identification tags were installed in addition to PT&P’s standard name plates per the customer’s request. Standard testing was performed and witnessed by an outside inspector prior to shipment.
There aretwo possible situations in which the constant would bottom out. One being theload is larger than anticipated and the other being that the amount of travelexceeds the total travel rating for that particular constant. Under the firstcategory, one would be able to increase the load by 10% if the conditionswarranted. Under the second category, replacement of the constant support wouldbe required.
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.
This 200 E-Type horizontal constant spring support is fabricated from carbon steel with a
hot-dipped galvanize finish. It is designed for a 54,020 lb. load with a total travel of 15.5″. The 3-bolt pipe clamp is designed for a 26″ diameter pipe and is coated with a red oxide primer. Each pipe hanger assembly went through standard load and travel testing prior to shipping. PT&P will design and fabricate any size constant spring support in addition to the sizes listed in our catalog.
Want to learn more about spring supports or clamps? Instantly view a past webinar now!
Sign-up for a Live Technical Webinar…
This presentation will cover pipe support design, 3D modeling, Finite Element Analysis, special stress, and thermal cases, along with the unique cases that brought on new pipe support designs. Increase your understanding of the value-added services that are offered by PT&P, and rest assured that your Engineering and Design needs can be covered by our 24×7 web-based emergency services, providing field service, and quick turnaround time when you need it most.
May 2nd: Variable Spring Support Design, Size Selection, Installation & Maintenance Webinar 10:00 am OR 2:00 pm
May 9th: Fabric Expansion Joints Webinar by U.S. Bellows, Inc. 10:00 am OR 2:00 pm
May 16th: Pipe Support Field Inspection, Installation and Maintenance Webinar 10:00 am OR 2:00 pm
Piping Design and Analysis Influence on Pipe Support Selection and Design
Surveying a piping system? Need to change a current system?
This course is also great for…
• New Engineers, Management and Operations
• Field, Process, Maintenance and New Engineers
• Piping and Piping System Designers and/or Instructors
*This online course is approved for 8 hrs. P.E. Credits
