Clean-in-place seals, or CIP seals, were developed to allow a seal to remain in place. This is especially important when the seal gland is partially open, allowing the seal to be flushed of debris.
In a food application, the same chemicals used to clean or flush the system would be used to clean the seal gland. Similarly, when other products such as pharmaceutical or adverse chemicals needed to be flushed, the CIP seal does an excellent job being open to flushing.
Rod wear rings play a pivotal role in hydraulic and pneumatic systems. By supporting the rod in the cylinder, they prevent metal-to-metal contact, which is crucial in minimizing friction and wear.
Piston wear rings, on the other hand, are designed to stabilize the piston as it moves within the cylinder. Their primary function is to prevent the piston from making direct contact with the cylinder wall, thus reducing friction and preventing damage.
Picture this: You have an application using a standard O-Ring. The O-Ring seals great, but is wearing out very quickly, and friction is far exceeding the goals of the system.
You retrofit a fancy PTFE spring energized seal that costs 1000 times more than the O-Ring…only to find out it leaks!
Did you get a defective seal? Is the seal designer incompetent? Is the raw material bad?
Actually, everything about the design and manufacturing of the spring energized seal could be perfect, and you could still find yourself with leakage.
While blaming the seal might be your first instinct, the leakage in fact, could have nothing to do with the seal itself, and everything to do with the surface finish of the hardware it’s trying to seal against.
Back-up rings serve an important role in world of seals. While the design principle and construction are incredibly simple, they greatly extend the usefulness of the most common and prolific sealing device in the world: the O-ring.
Back-up rings are aptly named as they do just that: they back-up an O-ring.
Back-up rings are commonly nothing more than a ring of polymer meant to space the O-ring away from the extrusion gap in hardware. By blocking off the extrusion gap, the pressure-handling ability of an ordinary O-ring is greatly increased.
Solid or split back-up rings out of virgin PTFE can usually be found on the shelf, and are largely considered commodity items.
V-Packings, also called V-Stacks or chevron packings, have been around for decades, and represent one of the earliest advanced sealing designs. While existing long before PTFE spring-energized seals came into being, they are still used in a variety of industries today.
Our partners at Eclipse Engineering design and manufacture their fair share of custom V-packings out of various materials every year. V-Packings offer a simple yet effective design principle.
A series of nested “V’s” are arranged in a gland where the points of the V’s serve as the sealing contact points in the hardware. They are designed in such a way that if the stack is compressed axially, the V behind will expand the radial cross-sectional width of the V in front of it. This will provide the needed energy to force the contacting sealing points into the hardware surfaces.
Compression force is usually provided by a packing nut in the hardware. The more the stack is compressed,
Rod scrapers, wipers, and excluders are common place in the seal industry. A wiper or scraper can be a critical part of keeping dust, dirt, and debris out of a hydraulic system.
While a polymer scraper such as a filled PTFE can provide many years of low-friction performance, some extreme applications need a more robust and aggressive design.
Our partners at Eclipse Engineering were approached by a customer using a hydraulic cylinder in a metal foundry.
Intense heat and marring media presented a challenging environment for
Neglecting routine maintenance can cost you in seal performance or, in some cases, end with catastrophic failure. Prolonged downtime will incur losses that exceed the temporary cost of preventative maintenance.
It’s important to identify seal contaminants and their sources before they turn into larger issues. Here are some tips on what to look for and how to deal with them.
Here are some typical contaminants you’ll come across:
In the world of engineering, machinery, and mechanical systems, dust can be the difference between a reliable piece of equipment and disaster.
Dust can cause major damage to cylinder walls, rods, seals and other components inside of machinery. And if you’re not careful, dirt, mud, debris, and water can all cause damage as well.
These foreign contaminants are real problems for mechanical systems, especially as they build up in small quantities over time. A single particle of dust today may be no big deal. But a speck of dust per day will eventually become enough of a presence to cause serious issues, like friction, surface wear, and imperfect seal contact between surfaces.
These issues could compound until the mechanical system experiences a complete failure. And in some applications, like in automobiles and aircraft, failure is simply not an option.
Beyond those industries, many types of equipment need to stay clean on the inside, even when things get extremely messy
The Channel Seal (or Cap Seal, as it’s often referred to), was one of the earliest forms of Polymer or Teflon sealing in the seal industry.
The product is easily applied. It didn’t replace the O-ring, but instead offered improved life while reducing drag.
In doing so, hydraulic and pneumatic systems operated cooler and quieter, while improving overall performance of the product.
Before the Channel Seal, the Backup ring was established. The first Backup rings started out as leather,
Rotary seals are often secured in sealing hardware by crimping the sealing element in a metal can. One of the most common rotary seals is a molded rubber lip seal in a can.
While not crimped, the can retains the sealing element, and stops the seal from rotating in the gland. Rotary sealing elements for low pressure (under 15 psi), are often nitrile or Viton rubber sealing elements.
This style of seal comes in many cross sections, and may include garter springs to help the seal stay engaged with the shaft. These seals are typically low in cost, and produced in high volume.
These seals are found in many low-pressure applications. However, as the pressures begin to climb over 10 psi and speeds run over 500 ft/min, friction generates heat,