by Sara McCaslin, PhD Sara McCaslin, PhD No Comments

Spring-Energized Seals for the Fluid Industry

Spring-energized seals have proven themselves indispensable in the fluid handling industry, alongside pumps, valves, fittings, and filtration. In fact, they serve as a precision technology to support key fluid handling systems. Canted coil springs enhance reliability, efficiency, and service life in fluid handling applications by providing precise force control, robust sealing, and long-term performance.

What Are Spring-Energized Seals? 

Spring-energized seals may look like ordinary polymer seals from the outside, but the difference lies within. A metallic spring is built into the seal, and its purpose is to maintain continuous contact between the sealing lip and the mating surface. That spring ensures the seal maintains the right amount of contact pressure, even when conditions fluctuate.

The design gives engineers a reliable way to handle problems that defeat traditional seals. Under pressure cycling, thermal changes, or material creep, ordinary seals can lose their ability to press tightly against surfaces. Once that happens, leaks are inevitable. With a spring-energized design, however, the spring compensates for those changes. It provides a consistent, repeatable load that keeps the sealing interface intact.

These seals are also highly versatile. Spring-energized seal jackets can be manufactured with advanced polymers such as PTFE, PEEK, or UHMW-PE. Engineering polymers such as this resist heat, wear, and chemicals. Combined with the spring element, they deliver performance that elastomeric seals or standard designs simply cannot match. The result is longer service life, reliable operation, and the ability to thrive in environments where ordinary seals fail.

In industries where precision is critical—fluid handling, aerospace, medical, and energy—spring-energized seals stand out as a proven choice. They bridge the gap between demanding operating conditions and the need for dependable, leak-free performance.

Why the Fluid Handling Industry Needs Advanced Spring Technology 

There are four key challenges in the fluid handling industry that can be addressed through the use of advanced spring-energized seal technology. These include large pressure fluctuations, exposure to aggressive chemicals, high cycling rates, and extreme temperature swings.

Large Pressure Fluctuations

When pressure inside a pump or valve spikes, a conventional elastomeric seal can lose preload. Eventually, they will deform, relax, and eventually fail to maintain a consistent sealing force. The result? Leaks and unpredictable system behavior. Spring-energized seals, by contrast, maintain nearly constant force across wide deflection ranges. Their unique geometry keeps seals energized and couplings secure, even when pressure swings from one extreme to the other.

Exposure to Aggressive Chemicals

Elastomers and some polymers will swell or crack when they encounter solvents, caustics, or sterilizing fluids. Once degradation sets in, seals fail quickly. Spring-energized seals solve that problem with corrosion-resistant alloys like stainless steel, Inconel, and Hastelloy. Pair canted coil springs with PTFE or PEEK seal jackets, and you have a system that resists attack and stays reliable, even in the harshest chemical environments.

High Cycling Rates

Pumps, valves, and quick disconnect couplings cycle millions of times in their lifetime. Standard seals suffer from fatigue, creep, and inconsistent force output long before those cycles are reached. That inconsistency leads to premature wear or outright leakage. Spring-energized seals are built differently. Their geometry spreads stresses evenly, allowing spring-energized seals to withstand high cycle counts while delivering the same force from start to finish.

Extreme Temperature Swings

Temperature changes wreak havoc on seals. Elastomers turn brittle in the cold, soften in the heat, and lose elasticity under cycling. Spring-energized polymer seals can continue to perform across cryogenic lows and elevated highs. Whether in sterilization cycles, hot fluid transport, or cryogenic handling, canted coil springs can keep seals energized and predictable.

The Takeaway

Every one of these challenges comes back to the same requirement: consistent, predictable seal force. Traditional approaches fall short, but spring energizers deliver the durability, adaptability, and precision needed to keep fluid handling systems running smoothly.

Applications in the Fluid Handling Industry

There are a host of applications for spring-energized seals in the fluid handling industry, starting with pumps and valves where they ensure long-lasting seals, both for static and dynamic applications. They are also very valuable in quick-connect/disconnect couplings, where they provide both secure retention and controlled release. In filtration systems, spring-energizers help to maintain seal integrity during pressure surges. These sealing solutions are also ideal for use with medical and pharmaceutical fluid handling, where there are FDA-compliant sealing solutions that can endure aggressive sterilization and cleaning processes. Finally, these seals are ideal for oil & gas fluid systems that operate under extreme temperatures and pressures in both topside and downhole equipment.

Conclusion

Robust, reliable sealing is absolutely necessary in fluid handling operations, regardless of the industry. Spring-energized seals for the fluid industry provide robust, reliable seals. They can address large pressure fluctuations, exposure to aggressive chemicals, high cycling rates, and extreme temperature changes. 

If you are designing a sealing solution for a fluid handling operation, contact us today at Advanced EMC to learn how spring-energized seals can positively impact the reliability and life of your system. Our engineers look forward to working with you.

by Bill Vardeman Bill Vardeman No Comments

Types of Seals for Oil and Gas Industry

seals for oil and gas

Seals used in the oil and gas industry must withstand high temperatures, high pressure, and a chemically hostile environment. The conditions limit the material used to make the seals for this industry. The most common types of materials include

  • PTFE
  • PEEK
  • UHMW
  • PCTFE
  • Hytrel

Let’s look further into these materials, their benefits, and their limitations. 

What is PTFE?

Polytetrafluroro Ethylene (PTFE) is a synthetic fluoropolymer with high-temperature resistance, commonly known as Teflon. It is a hydrophobic, high-molecular-weight polymer consisting of carbon and fluorine.

Benefits of Using PTFE

PTFE is ideal for use in the oil and gas industry as it is resistant to extreme high and low temperatures. In addition, PTFE has a low coefficient and a low dielectric constant. Finally, the hydro resistance nature of the material makes it a top choice for working with steam or heated seawater. 

One of the most significant benefits of using PTFE is the resistance to harsh chemicals. It has the broadest chemical resistance of commercial polymers. For example, seals made of this material are resistant to hydrogen sulfide, ferric chloride, ferrous sulfate, hydrochloric acid, and hydrofluoric acid. 

Limitations of PTFE

PTFE’s limitations make it unsuitable for some uses. For example, it is sensitive to creep and abrasion, requiring regular maintenance. PTFE also has low radiation resistance and can corrode and produce toxic fumes as it breaks down.

Properties of PTFE

PTFE has a density of 2200 kg/m3 with a melting point of 327°C (620°F). PTFE maintains self-lubrication, strength, and toughness at temperatures down to -268 °C (-450.67°F). Additional properties include:

ptfe seal used by oil and gas

What Are Some Common Oil and Gas Applications of PTFE?

PTFE is one of the more common materials used in oil and gas seals. For example, O-rings, slipper seals, backup rings, piston rings, and spring-energized seals use PTFE material. In addition, natural gas, cold media seals, bearings, and wear components also use PTFE for manufacturing.

 

What Is PEEK?

Polyetheretherketone, or PEEK, is a colorless organic thermoplastic semi-crystalline polymer with excellent mechanical and chemical resistance properties. It’s high-resistance to terminal degradation makes it useful in oil and gas environments.

Benefits of using PEEK

As with PTFE, PEEK has several benefits for oil and gas companies. It has good dimensional stability and chemical resistance. In addition, PEEK is resistant to gamma radiation and X-rays.

PEEK has high mechanical strength and is ideal for high vacuum applications. Its robust nature makes it suitable for demanding applications such as the oil and gas industry. It works well in compressors, pumps, and pistons.

Limitations of PEEK

Despite PEEK’s many benefits, there are some drawbacks to using this material. It has low UV light resistance. It is also unsuitable for nitric acid, sulphuric acid, sodium, and halogens. In addition, it is expensive to make and requires high temperatures to process. 

Properties of PEEK

PEEK has a high tensile strength of 25000 to 30000 psi. It has a V0 flammability rating of 1.45mm and can withstand high loads for extended periods without residual damage. Additional properties include:

What Are Some Common Oil and Gas Applications of PEEK?

Labyrinth, spring-energized piston seals, backup rings, and seal packing in the oil and gas industry are manufactured using PEEK materials. In addition, it is the material most often chosen for the face seals at the wellhead to contain the high-pressure production of gas and fluid.

What is UHMW Polyethylene?

Ultra-High Molecular-Weight, UHMW, Polyethylene seals are thermoplastic, semi-crystalline materials. It is lightweight with a high-pressure tolerance that makes it ideal for spring energized seals used by the oil and gas industry.

Benefits of Using UHMW Polyethylene

Seals made from UHMW have the benefit of being both abrasion and impact resistant. This self-lubricating material has a low friction coefficient. It withstands extreme colds and high temperatures.

 It has a high molecular weight, meaning UHMW is not likely to melt and flow as a liquid. This material cannot be molded by traditional methods, thanks to the high molecular weight. Instead, it is compression molded to make it stronger.

Limitations of UHMW Polyethylene

While UHMW Polyethylene has many benefits for the oil and gas industry, there are some limitations, such as having a lower maximum continuous surface temperature than other materials. 

UHMW Polyethylene has a compressive strength of 3000 psi. In addition, it has a maximum safe workload of 1000 psi in some industries. Overload can cause UHMW polyethylene to crack or break.

Properties of UHMW Polyethylene

UHMW polyethylene seals are self-lubricating and have low surface energy, which makes them ideal for the oil and gas industry. Other UHMW polyethylene properties include

uhmw seals used by oil and gas

What Are Some Oil and Gas Applications for UHMW Polyethylene?

UHMW polyethylene material is used for seals in the oil and gas industry. It is used to make spring energized seals. It is also used for cargo dock impact bumpers and liners.

What is PCTFE?

Polychorotrifluoroethylene (PCTFE) is a chemical compound with a high tensile stretch and good thermal properties. Its chemical-resistant properties make it ideal for use in the oil and gas industry for seals and other components.

Benefits of Using PCTFE

Seals made with PCTFE are nonflammable and heat resistant up to 175°C (347°F). They are also resistant to acetone, hydrochloric acid, sodium peroxide, citric acid, and sulfuric acid. It is water-resistant as well.

PCTFE has a board temperature range with a useful temperature range of -204.4°C (-400°F) to  193.3°C (380°F). When comparing PCTFE vs PTFE, PCTFE is a stronger polymer with better mechanical properties.

Limitations of PCTFE

PCTFE has many beneficial properties for the oil and gas industry. However, some limitations, such as a lower melting point when compared to PEEK or PTFE, might make it less desirable. Seals used in extreme temperatures may need to be a different material.

Additionally, PCTFE is a stiffer material. While this does allow it to maintain its dimensions better, it does break easier than PTFE. Along with being stiffer, it is not as non-stick when compared to PTFE.

Properties of PCTFE

PCTFE has V-0 flammability and a hardness of 67 at 100°C and 80 at 25°C. Other properties include

 

 

What Are Some Oil and Gas Applications for PCTFE?

Like PEEK or PTFE, PCTFE is a great material for seals in the oil and gas industry. It’s chemical resistance, which means it can be used in the most volatile industries. Fillers within the seals can enhance some of the properties. PCTFE is also used in component designs and valve seats.

What is Hytrel?

Hytrel is a thermoplastic polyester elastomer that is plasticizer-free. It is a stable material with needed flexibility while handling high temperatures. It is a worthwhile option to consider for the oil and gas industry.

Benefits of Using Hytrel

As a seal material for the oil and gas industry, Hytrel has good chemical resistance. It can withstand exposure to fuel, hydrocarbon solvents, and oil. Additionally, as the material is exposed to higher temperatures, it becomes more rigid. At lower temperatures, it is more flexible.

Hytrel is abrasion resistance. It offers impact and creep resistance to the seals. It also is resilient and excels at providing flex fatigue and tear resistance. Hytrel has a natural spring-like property and has low hysteresis.

Limitations of Hytrel

As there are several models of Hytrel, only a few are best for use in seals. Hytrel 4556, 4056,4068,4069, and 6356 are the ones that work best. However, these don’t always work well in the oil field, so you should know which ones to look for.

Properties of Hytrel

Hytrel has V-0 flammability and a hardness of 67 at 100°C and 80 at 25°C. Other properties include

 

seals for oil and gas

 

What Are Some Oil and Gas Applications for Hytrel?

Hytrel is useful as a seal material in the oil and gas industry. As it is resistant to many chemicals, including hydrocarbon solvents, it is ideal for hazardous conditions.

Which Seal Type is Best for the Oil and Gas Industry?

Each seal type has its uses and benefits for the oil and gas industry. However, the best options are PEEK, UHMW, PCTFE, and Hytrel. It is because they have the best physical properties to withstand the harsh conditions in the oil and gas field. 

At Advanced EMC Technologies, we offer custom-engineered sealing systems that provide reliable sealing solutions. Our seals perform under high temperatures, high pressure, and chemically hostile environments. Contact us for more information.

 

Seals for Oil and Gas Industry FAQ

IS PEEK environmentally friendly?

There is no evidence that PEEK has a significant environmental impact in its service life, disposal, or manufacturing. Toxicity is low and does not contain anything known to be toxic. There is low smoke, poisonous gas emissions, and fire when involved in a fire.

What are spring-energized seals?

Spring-energized seals can store mechanical energy by compressing the spring. As a result, they withstand more pressure and heat than their conventional counterparts. In the end, the mechanical energy stored in the seal keeps it from leaking.