The design parameters that must be considered when selecting a pipe hanger would include operating temperature, operating load, movement, pipe material, available space, and allowable initial load requirements. Once these are known, then you can select an appropriate type of pipe hanger which could be any of the following types including rigid hangers, variable spring hangers, or constant spring hangers.
Variable Spring Hanger Installed in the Field
A spring hanger is a subset of either variable or constant spring supports that attach directly to structural steel components and are located above the supported member.
Constant Spring Hangers
Piping Technology and Products, Inc. recently fabricated 22 Carbon Steel PTP 200-C type Horizontal & PTP 100-C type Vertical Constants with sizes from 3 to 27. The load capacity of the constants spans between 215 to 2650 lbs., with a travel ranging from 1” to 4”. The three bolt clamps are fabricated from stainless steel material A 240 Gr. 304 for 4″ to 8″ dia. pipes. The rod and turnbuckle were shortened on two of the constants in order to accommodate situations of small rod take out. Standard load and adjustment testing was performed.
Want to learn more about constants? Instantly view a past constant webinar today!
Piping Technology & Products, Inc., custom designed and fabricated a collection of constants for an oil refinery in New Jersey. This application required the use of suspended constants, 100-C and base constants, 200-F.
In order to support the lines at the oil refinery, PT&P designed the 100-C constant spring hangers (vertical constants suspended from beams) at two different loads and total travels. The 100-C constant with a load of 105,000-lbs. and total travel of 6″ (figure 1) is set to travel 1-3/4″ down and 1-15/16″ up. It is 38-3/8″ in width, 79-1/4″ in height and furnished with a double lug suspension to allow it to hang from a double point suspension beam.
In comparison to the aforementioned constant, this particular 100-C constant spring hanger (figure 2) has a load of 33,000 lbs. and a total travel of 4-1/2″, 3/8″ up and 1-1/2″ down. This specific constant is 24-1/4″ in width, 71″ in height and also furnished with a double lug suspension to suspend from a double point suspension beam. Although the dimensions of these two constants are similar, the size of the springs and cams are very different.
Opposed to the 100-C constant, the 200-F constant spring hanger is a horizontal constant used to support piping from below. These 200-F constant spring hangers were designed with loads of 40,750 lbs. and total travels of 4-1/2″, 3/8″ up and 1-3/4″ down. These constants will be used in conjunction with sway struts to support pipelines at the oil refinery.
Learn more about constants spring hangers by visiting our website archives!
A large refinery plant located in Pasadena, TX called upon Piping Technology & Products, Inc. to aid them in the immediate replacement of a 5400 Lbs, 7 1/2″ travel vertical constant spring hanger used to support a Coker drum.
The constant spring hanger was damaged during servicing. The reliability engineer from the refinery contacted PT&P Wednesday evening to request an inspection by a PT&P field services representative. The following morning PT&P’s field services representative arrived on-site, inspected the damaged constant spring hanger and suggested that a replacement would be most efficient and cost effective. With the existing nameplate bolted to the constant, PT&P was able to easily locate the original design of the constant.
The original design, along with the convenience of the component parts being in stock inventory, allowed PT&P to quickly manufacture a replica of the constant and ship it out on the same day by 6 p.m.
In the past, lead times for delivery of constant supports averaged 6-8 weeks, however, through the process of maintaining stock components of interchangeable parts, lead time has been drastically reduced. Piping Technology & Products, Inc. maintains a large inventory of stocked constant support assembly components that allows them to quickly assemble and ship to customers on demand, especially in emergency/quick-turn situations.
Sign-up for a Live Technical Webinar…
Learn how the theoretical applications of spring supports are put into use in the real world. We will start with a review of the working principles of both variable and constant springs. See how brand new spring looks at delivery, and review installation guidelines. Learn the key points to review through the total installation process and subsequently when the springs are in operation. See how to determine if springs need adjustments, re-calibration, refurbishment, or replacement. View in field examples, shutdown, and isolation procedures. See the selection process required when there are significant changes to the operating condition.
April 25th: Pipe Support Engineering & Design Webinar 10:00 am OR 2:00 pm
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
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
