The O-Ring & Engineered Seals Division of Parker Hannifin Corporation, the global leader in motion and control technologies, recently announced the launch of VA179, a new extreme high temperature fluorocarbon (FKM) compound. VA179 is an innovative, 70 durometer rubber seal material providing increased high temperature limits while maintaining chemical resistance and low temperature sealing consistent with standard FKMs.
VA179 consists of a breakthrough rubber technology increasing the FKM continuous high temperature limit an additional 20°C (68ºF) over standard FKM materials on the market today. This provides a new industry sealing solution to long-term compression set issues for customers using traditional fluorocarbons and silicones.
“In markets such as aerospace, automotive, and heavy-duty, we are frequently challenged to expand the temperature capabilities of our rubber compounds,” says Nathaniel Sowder, aerospace, military and chemical processing business development engineer, O-Ring & Engineered Seals Division, “With the launch of VA179, we now have a solution that will reach higher temperatures without sacrificing the low temperature and chemical resistance attributes that make standard FKM such a popular choice.”
In the late nineteenth century, Olin J. Garlock devised a better way to seal piston rods in steam engines. Since then sealing materials have been developed for various industrial applications. Over the years, different manufacturing processes such as calendering and beater addition have improved the performance of fiber sheet gaskets for these applications; however, design concepts for their formulation remain similar regardless of manufacturing method.
OVERVIEW OF MATERIALS
Many of the applications for compressed fiber sheet gaskets involve elevated temperatures and/or high pressure, which require high bolt loading in flanged joint assemblies. Various materials are added to the fiber-binder matrix to sustain this high compressive loading. To provide strength, different types of fibers such as p-aramid (Kevlar™), cellulose, polyester, glass fiber, carbon fiber, and others are added. Some of these fibers are organic materials, which limits their use at elevated temperatures. Minerals in cylindrical form provide balance in the formulation due to their high-temperature stability and strength. To form a compact structure, materials of different sizes are used, including silica, carbon black, and other micro-sized fillers. Figure 1 illustrates the ingredients and microstructure of a compressed fiber sheet material.
DuPont™ Kalrez® 7375 FFKM sealing products provide high temperature as well as broad chemical and water/steam resistance properties. Sealing performance, reliability and safety are ensured for applications in the most demanding industrial, chemical and general industrial fields of operation.
These high performance perfluoroelastomer O-ring components are available from Gallagher Fluid Seals, the authorized distributor for a wide range of DuPont™ finished O-rings, as well as custom shapes, sheets and cord sealing components.
The Kalrez® 7375 parts are tailored for specialized chemical applications covering broad operating temperatures from -20°C to 300°C (-4ºF to 572ºF).
These products, which incorporate patented cross-linking technology, combine both superior chemical resistance with a thermal stability which exceeds many other competitive FFKM products. They are also available in most standard O-ring sizes including AS568, metric and JIS, with custom sizes and shapes also available on request.
Cement and aggregate facilities are dusty, dirty, humid environments. Sand, gravel, crushed stone and water are in use in many forms throughout the facility. Keeping solid particles and water vapor out of oils and machinery is important.
Mobile equipment such as cranes and shovels are used to move materials around the facility or place them on conveyor systems. They are also used to dig or dredge the sand and gravel from lakes, rivers and streams. Hydraulic systems and gearboxes on the mobile equipment are subjected to dust and humidity continuously. Protecting the oils from water vapor and solid particulates keeps the systems running smoothly.
Bulk material handling terminals load, unload and store the fine and coarse aggregates. The conveyor systems are used to move various materials. Each system is equipped with large drives, gearboxes and bearings that have oil and lubrication reservoirs. Air Sentry® breathers provide protection from airborne dust and moisture.
Can electrically conductive plastics really replace traditional metal electronics enclosures? The answer is a resounding yes! There are very effective electrically conductive plastics available today that provide excellent electromechanical properties that help shield portable electronics from the electromagnetic interference (EMI) noise that is proliferating our daily life. Smart phones, Bluetooth, Wi-Fi, radio, even your television are all susceptible to EMI. So here are the key points you may want to consider when evaluating electrically conductive plastics for your application:
#1: Shielding Effectiveness
Every day we encounter EMI, and sometimes it happens at the most inopportune time. Maybe you’ve been put on hold for an hour and just when the customer service agent gets back to you, your cell phone drops the signal. Or perhaps you’re blasting the car radio listening to your favorite song, and just when the chorus comes on, static noise drowns out the tunes as you drive under high tension power lines. These are all examples of EMI interfering with our daily life, and electrically conductive plastics can help shield our portable devices from these interruptions.
Vesconite’s origins lie in the gold mining industry, a notoriously harsh working environment. The product was developed as a maintenance-free alternative to bronze bushings traditionally used in mining equipment. Unlike bronze, Vesconite eliminates three key issues: The need for regular lubrication; the effects of dirt and grit on costly components; the damage caused by water to traditional bushing materials. Vesconite offers up to 10 times the lifespan of traditional bushes in these harsh conditions, and saves hours of downtime caused by machines requiring frequent lubrication.
Vesconite Bushings on a Vertical Borer Stabilizer Rod
South Africa – A earth-boring company was looking for a durable material to create stabilizers for its borer machines. The machine bores between levels in mines and is capable of boring chutes up to 120m. The drill steel is subject to high levels of grit and rock. The Vesconite stabilizers help align the drill steel, thereby avoiding whip in the drill. Despite the dirty conditions, the new stabilizers required no lubrication between recommended overhaul schedules, and general maintenance and downtime were substantially reduced.
Gallagher recently recorded theRubber Energized Seals webinar, discussing rubber energized rod or piston seals, and the advantages and disadvantages to using some of the most common seal profiles. This webinar is presented in conjunction with one of our trusted partners, Eclipse Engineering, Inc. Eclipse is a designer and manufacturer of high performance engineered polymer solutions.
This section of the webinar will discuss cost vs. lead time in rod and piston seals, as well as how to choose the right seal for your application.
To view the webinar in its entirety, visit our Resources page and fill out the form, or click on the image below.
KLOZURE® Oil seals from Garlock® KLOZURE® are available in a wide variety of configurations to meet the requirements of major industries. MILL-RIGHT® materials are used on all elastomeric seals for superior bearing protection. KLOZURE® Oil Seals are available in more than 50 different styles in sizes from ¼” to over 90″, solid or split, metal-cased or all-rubber. KLOZURE® Oil Seals have had a strong brand presence in the U.S. since the 1920’s. Today they are also manufactured and branded in China and Germany. Technology has advanced over the years, and the oil seals are now available in MILL-RIGHT® elastomers which provide longer service life than their predecessors.
There are many different styles and variations available from Garlock® KLOZURE®, but below are some of the more popular oil seals.
Gallagher Fluid Seals recently added the Rubber Expansion Joint Surveys & Failure Analysis white paper to our Resources page. This white paper discusses the importance of inspecting your plant’s expansion joints. Proper design and maintenance of rubber expansion joints plays a major role in the overall preservation and lifespan of a piping system.
It will also discuss failure analysis of rubber expansion joints and some of the leading causes of joint failure.
Below is an except from the white paper, discussing failure analysis of rubber expansion joints, and what it can tell you about the overall health of your piping system.
There are perceptible warning signs when an expansion joint is failing:
Arch inversion indicating a system vacuum that has exceeded the joint’s specified expansion value.
Cracking at the base of the arch, which indicates the joint has been over-elongated and should be replaced with one of the proper length.
Ply separation on the outside of the cover. This is an indication the joint has been subjected to excessive movement.
Leakage due to over-expansion, mating flange surface issues, or poor installation practices, especially (but not limited to) bolt tightness.
Ballooning of arch, which indicates excessive system pressure.
Reduce Exhaust Leakage in Heavy Duty Engines by 80 Percent with an Air Duct Seal
Increased emission restrictions are requiring engine manufacturers to conform to Euro 6 and Tier IV regulations to reduce exhaust leakage 80% or more. In order to achieve these new standards, engines with extreme temperatures coupled with a high amount of vibrational movement, need to have highly engineered sealing solutions. Applications with predetermined mating components cannot always be changed, so the need for a sealing solution with a similar coefficient of thermal expansion is needed.
What is the problem in existing exhaust applications?
Most heavy duty diesel engines can reach exhaust gas temperatures upwards of 1292°F(700°C) while subjected to constant vibrations. These engine vibrations can cause havoc when a seal needs to be maintained on the exhaust line. Vibrations from the engine cause rotation, cavity offsets, pivoting, and reciprocation which become difficult to seal against. Movement, pressure cycling and thermal cycling require an engineered solution to maintain a seal under extreme application conditions. With the use of custom engineering and advanced analysis techniques, Parker is able to create custom solutions for our customers’ most difficult applications.