metal seals
- June 22, 2021
A metal seal is used when the application conditions are outside the specification limits of a polymer; extreme heat, extreme cold, extreme pressure, or a vacuum. With significant resilience coupled with the right material selection/coating for an application, a metal seal can be a very durable seal performing dependably year after year.
O-FLEX™ METAL SEAL O-RINGS
O-FLEX™ metal O-rings are designed to provide a sealing option for high-pressure/high-temperature applications that require minimal spring back. The O-FLEX™ metal O-ring is made from high strength metal tubing that is coiled, cut and welded to size. It is available in standard cross-section increments of 1/32”. The O-FLEX™ metal O-ring seating load can be adjusted to the application by varying the cross-section and tubing
- December 31, 2020
Failure is not an option in the most demanding sealing applications. Valves continually strain the capabilities of sealing solutions, and elastomer solutions are often not enough. The unparalleled reliability of high-performance metallic seals from our partners at Technetics can help excel in the face of these challenging scenarios.
In these extreme environments, high-performance metallic seals combine state-of-the-art engineering with advanced materials design to deliver a product that exceeds expectations and stands up to the rigors of these applications.
Why Use High-Performance Metallic Seals?
Traditional sealing methods, such as elastomers or graphite seals, present limitations when extreme environments come into play. Under the tremendous workload of valves in these applications, they can lose tightness or deform, presenting distinct challenges.
- October 08, 2020
At Gallagher, we often receive unique requests for challenging projects, and customers who might be intimately familiar with elastomeric seals might have a better fit utilizing metal seals for their application. But, why might someone use a metal seal?
A metal seal is used when the application conditions are outside the specification limits of a polymer; extreme heat, extreme cold, extreme pressure, or a vacuum. With significant resilience coupled with the right material selection/coating for an application, a metal seal can be a very durable seal performing dependably year after year.
In order to understand metal seals a bit better, GFS thought it might be worthwhile to discuss metal seal terminology, and different profiles.
This is a short guide to reference common terms and profiles that may to new to end-users.
In this blog post, we will discuss the following:
- Common terms of metal seals
- Standard formed metal seals
- O-rings
- C-Rings
- Spring energized C-Rings
- U-Rings
- E-Rings
- Metal Wire Rings
- Axial C-Seal
- Boss Seal
But first, let's go over some common metal sealing terms.
- September 16, 2020
Article re-posted with permission from Parker Hannifin Sealing & Shielding Team.
Original content can be found on Parker’s Website and was written by Vivek Sarasam, heavy duty mobile Sr. application engineer, and Jeffrey Labonte, market manager.
Parker Hannifin Engineered Materials Group has developed a wide variety of metal seals which can be formed or machined. A metal seal is a highly engineered sealing solution which provides elastic recovery or spring back to maintain good sealing, despite separation of mating surfaces due to effects of thermal cycling, flange rotation, applied mechanical or hydrostatic loads or creep.
Why use a metal seal?
A metal seal is used when the application conditions are outside the specification limits of a polymer. For example, when:
Temperature is too hot or too cold & pressure is too high or there is a vacuum.
Metal Seals are primarily used in static applications for temperatures as high as 1000°C/1832°F and pressures as high as 6825 bar/99000 psi for select applications. At low cryogenic temperatures and low pressures, such as vacuum seal applications, metal seals are far better than polymers since they do not become brittle and lose elasticity. Metal seals also have a low leakage rate down to 1 x 10-12 cc/sec per mm circumference which in comparison to high load O-rings is almost 100x better.
Medium is corrosive and seal longevity is needed.
Unlike elastomer seals, metal seals are very highly resilient to corrosive chemicals and even intense levels of radiation. With this resilience coupled with the right material selection/coating for an application, a metal seal can be a very durable seal performing dependably year after year.
Parker has a variety of in-house developed coatings which are used based on the application conditions and base material. The chart on page D-59 of the Metal Seal Design Guide (shown below) shows examples of some of the coatings based on the base material.
What X-sections can be made?
Metal seal x-sections can vary from a solid O to a Hollow O and from a C Ring to an E Ring depending on the application load and allowable leakage rate as shown in the figure below. Each x-section has benefits based on the application use and cost as indicated in the chart below.
Page A-10 of the Metal Seal Design Guide (shown below) shows some common applications in the industry and the type of metal seal used in those applications. These are examples of applications where the application conditions exceed beyond what an elastomer is capable of handling.
Importance of surface finish for metal seal applications
- July 29, 2020
Spring-energized metal seals provide numerous advantages in oil and gas applications, including but not limited to MWD and LWD tools, couplings, subsea compressors, enclosures/vessels, christmas trees, electronic submersible pumps and flowmeters. Extreme operating pressures and temperatures, together with more difficult resource recovery, zero tolerance for failure and environmental concerns, are placing unprecedented demands on this equipment.
Traditionally this industry has used solid machined seals that provide high compression loads but lack resilience. They also tend to have relatively high rates of leakage over time as flanges deteriorate. Recent advances in metal seal technology provide controlled compression, high resilience and reduced leakage.
Background
- January 24, 2020
Article re-posted with permission from Parker Hannifin Sealing & Shielding Team.
Original content can be found on Parker’s Website and was written by Thorsten Kleinert, Business Unit Manager, Composite Sealing Systems Engineered Materials Group, Europe.
When classic sealing materials reach their limits, such as temperature ranges above 300°C and below -50°C – alternative materials are sometimes required, such as metal seals with appropriate coating/plating.
Parker offers metal seals made of stainless steel or nickel alloys in