FAQ Series: How Does Pipe Spring™ Save Your Company Money? How Much Does It Cost?

Close-up Of Businesswoman Holding Hourglass Near Stack Of Coins

Question: How Doe Pipe Spring Save Your Company Money?

Answer: At least three major areas of cost are typically involved with pipeline repair or field integrity work. These are:

  • The direct procurement cost of the repair product
  • The direct labor cost or man-hours of the installation
  • Potential for operational changes, cost elimination, or organizational changes to reduce cost

The direct procurement cost of Pipe Spring™ is often significantly lower than alternative competitive systems. On one recent RFQ, Pipe Spring was only 50% of the cost of a popular composite alternative. Based on our understanding of the pipe integrity marketplace, we strongly believe our products will cost less.

The direct labor cost or man-hours of the actual installation can also be lower as installation time is faster. This can mean more repairs per day, more per week, and more repairs for lower project costs. This is an opportunity to do more with less spending while utilizing a product with better integrity.

The potential for operational changes to integrity efforts are also very real. From the elimination of extra supervision, elimination of additional inspections, and the removal of the need to weld at multiple dig sites, our product creates an opportunity for efficiencies. The ease of installation enables opportunities for additional tasks to be completed.

Some of these costs savings are easy to quantify and easy to capture such as spending less to buy a repair product. Some involve more effort at a project management level and the cost containment of projects.

Below is a specific example:

A pipeline company emails Pipe Spring LLC and explains they have a 16-inch diameter pipe. It is Grade B and has a wall thickness of .325-inch. A Pipe Spring™ kit that will repair up to 79.9% wall loss costs about 30% less than the material for a popular composite offering*. Project delays can be avoided and the excavation is opened and closed the same day.

Contact us at [email protected] for your quotation today.

*Based on recent client communications


FAQ Series: Is Pipe Spring™ PHMSA Approved?

Question: Is Pipe Spring™ approved by PHMSA?

Answer: The Pipeline and Hazardous Safety Administration (PHMSA) does have safety jurisdiction over many pipeline assets located in the USA. However, it is important to understand PHMSA does not approve any product or specific technology.

49 CFR 192 specially allows repairs “by a method that reliable engineering tests and analyses show can permanently restore the serviceability of the pipe.” 49 CFR 195 has slightly different language. It is widely agreed that pipeline operators have flexibility to adopt new technology and are required to document the “reliable engineering tests and analyses” which serve to address the decision.

Operators are also required to include their repair technologies within their operating and maintenance (O&M) language.

Pipe Spring LLC has compiled a significant body of engineering tests and analyses to help satisfy the operator’s requirements to document these items. They are available to operators upon request as one package that will satisfy this regulatory requirement.

Prior to use on regulated pipelines, operators may want to amend their existing O&M language or approved repair lists referenced in their O&M language to include Pipe Spring™.

FAQ Series: How Does Pipe Spring™ Compare to Composite Repairs and Welded Steel Sleeves?

Question: How does Pipe Spring™ compare to composite repairs?

Answer: Pipe Spring™ utilizes material, steel, to wrap around the pipe. Composites utilize material, thermoset resin reinforced by fibers, to wrap around the pipe. The reinforcement mechanisms and concepts are similar.

Composites are best thought of as thixotropic material. The resin and fibers can move and change over time. They are known to display a degradation in mechanical properties over time particularly when exposed to specific environmental conditions or to various chemicals. Composites can be designed to be very anisotropic and have very different strength in various directions. For pipeline applications, two broad categories of composites are common:

  • Pre-cured laminated composites applied in the field with adhesives systems
  • Wet applied systems that are comprised of a strength member (fibers) and a thermoset resin which is wet when applied.

A properly designed repair must be based on the degraded or long-term failure strength of the composite material. The degradation during service life of the effective modulus of elasticity of composite repairs remains an area of some controversy related to long term effectiveness.

Pipe Spring™ is not a composite repair. However, it is installed in a similar fashion to the pre-cured laminated composite systems. Recent advances in technology have enable a minimization of field variables and simplification of installation. Efforts have been made to make the installation system as quick, simple, and repeatable as possible.  This is intended to save operators time and money and result in excellent quality installations. Wet applied composites systems can require specific skills and experience for effective long term repairs. This can result in greater installation costs. The isotropic, homogeneous, and non-degrading material properties of steel result in thinner repairs. The axial strength provided can be calculated in addition to the traditional hoop stress models. The fracture toughness of the Pipe Spring™ steel sleeve is extraordinarily high due to the thin-layers and laminated design. This property is beneficial for mitigation of future potential mechanical damage.

Additionally, for Strained based concerns, Pipe Spring™ significant advantages:

  • Axial strength
  • Non-degradation of material properties during service life (strength and modulus)
  • Initial stress/strain response
  • Improved bulk effective modulus of elasticity.
  • Cyclical performance of adhesive system (10 million cycles)

Question: How does Pipe Spring™ compare to welded steel sleeves?

Answer: Pipe Spring™ is a modern version of a “Type A” sleeve with the welding eliminated and adhesive utilized to hold the sleeve together. “Type B” sleeves have circumferential fillet welds at the end of each sleeve to join the pipe body and sleeve as one welded unit. “Type B” sleeves are sometimes utilized when leaks are projected to become a threat. The fillet welds are intended to contain the potential leak.

Some operators decline to utilize “Type A” sleeves, as they provide no axial strength and they would not contain pressure in the event of a leak. Some operators decline to utilize “Type “B” sleeves due to concerns related to metallurgical effects of welding on vintage pipe often with thinned walls due to external and/or internal corrosion. There are also safety concerns related to burn thru via high temperature welding arcs.

Some operators prefer to avoid welding “on” or “to” the pipe at all based on safety concerns related the welding process near the product being transported within the pipe. Welded steel sleeves can also be quite thick and heavy and require significant material handling and welding time. They may also require delayed weld inspection. Welded steel sleeves can be expensive to install and difficult to achieve the necessary quality desired. Fit up issues related to ovality or the presence of longitudinal welds also create a list of specific concerns. The welds created to hold the welded steel sleeves together can ultimately be the limiting life factor related to cyclical performance.

Pipe Spring™ provides the known behavior and properties of steel while eliminating the need to weld.


FAQ Series: How Does Pipe Spring™ Work? What Integrity Threats Does Pipe Spring™ Address?

Question: How does Pipe Spring™ work?

Answer: The laminated steel sleeve reinforces the existing pipe.

For metal loss defects: The thinned section of the existing pipe will tend to display strain and will begin to bulge and yield in the radial direction due to internal pressure. A threat to the pipeline integrity exists. With a properly installed Pipe Spring™ sleeve, the thinned ligament utilizes the high compressive strength filler material to transfer the load to the laminated steel sleeve. The steel sleeve then shares the stress with the pipe. Metal loss defects cannot bulge and yield. Metal loss defects are effectively mitigated.

For integrity enhancement applications: Wet uncured filler material is placed around any weld or protuberance from the pipe surface. The thin layer steel is wrapped around then pipe with the adhesive system applied between each layer. Out-of-round or ovality of the pipe is addressed by the conformity of the thin layer steel and the filler. The system quickly transfers load to the resultant steel sleeve. The engineering parameters of the steel sleeve augmentation can be calculated for hoop and axial strength. This can be added to the known minimum value of the pipe (perhaps recent known pressure if the grade of the pipe is unknown). The effective fracture toughness of the laminated steel sleeve is extremely high. The reduction in stress via the augmentation and the fracture toughness of the augmentation can be utilized for calculations related to fracture mechanics. The laminated steel sleeve augmentation provides excellent mitigation of potential future third-party mechanical damage.

Question: What integrity threats does Pipe Spring™ address?

Answer: Pipe Spring™ is a modern version of a “Type A” sleeve with the welding eliminated and adhesive utilized to hold the sleeve (coil) together. The list of integrity threats which are properly addressed by a “Type A” sleeve is also the appropriate list for Pipe Spring™. In addition, Pipe Spring™ is adhered to the pipe via a high strength adhesive. Effective axial strength can be calculated as the lesser of the adhesive bond strength to the pipe or the axial strength of the steel sleeve for the appropriate cross-sectional area. Pipe Spring provides axial strength to mitigate threats with an axial component.



FAQ Series: What is Pipe Spring™? Why Use Pipe Spring ™?

Question: What is Pipe Spring™? 

Answer: Pipe Spring™ utilizes thin layer steel and a modern toughened adhesive system to create a laminated steel sleeve system. A two-component epoxy system is used as a filler material and to fill any area of metal loss or around any weld or other protuberance on the pipe. The resultant steel sleeve provides reinforcement to the pipe and effectively mitigates various integrity threats. It can be used as a repair system. It can also be utilized to augment existing pipe for purposes of:

  • Change in design factor
  • Class location change
  • Pressure increase
  • Providing additional known properties so that your pipe can become Traceable Verifiable and Complete (TVC) and can be properly documented

Question: Why use Pipe Spring technology?

Answer: The Pipe Spring system was conceived to minimize or eliminate several challenges with existing technology and to utilize several opportunities to make improvements to pipeline repairs and integrity efforts.

Existing repair options present challenges!

Issues with Welded Steel Sleeves:

Welded steel sleeves require welding. The safety of the repair could be maximized if welding near the fluids carried within pipelines could be eliminated. The preferred method’s design guidance of welding on pipe and pressure vessels as well as cyclically loaded structures) strives to eliminate all partial penetration welds, use fillet welds only for shear applications, avoid striking arcs on the body of the weldment, and using subsequent weld beads to refine grain size. Welded steel sleeves for pipeline repair applications tend to violate some of these traditional best practices. In addition, the fit up to pipe is not always perfect. The result is less then optimum performance.

Issues with Composite Repairs:

Composites repair options eliminate the welding issues but introduce another set of challenges. Composites repairs degrade over time. Both the strength and effective modulus of elasticity may degrade. Thicker repairs are required to handle the strength issue. The modulus issue is not often addressed. The architecture of specific composite repairs can result in the requirement to have fibers straighten prior to sharing the stress from the pipe. The initial stress/strain response can display a significant delay. Some systems can require significant skill and care during installation.

The advantages of Pipe Spring™:

  • Thin layer steel conforms to out-of-round conditions or ovality
  • Steel does not degrade over time and has isotropic properties
  • The Pipe Spring system can provide axial strength
  • Faster Initial stress/strain response
  • Improved effective modulus of elasticity
  • Pipe Spring allows for thinner repairs, easier installations, and less soil stress
  • Improved cyclical performance
  • Improved long term performance
  • Intrinsic mitigation of potential damage to repair (laminated design)
  • Ease of Installation
  • Strain dependent concern mitigation
  • ILI visible and the system is ILI inspectable (MFL)
  • No heavy equipment needed for installation
  • Not dependent on skilled welding ability or advanced installation techniques