Tech Talk Blog

Accelerated aging is a testing method that enables us to estimate the potential lifespan or shelf life of a product when actual data is unavailable.  For instance, products may be subjected to unusually high levels of stress, or mechanical parts may be run at speeds far above normal.  In the case of polymers, they may be kept at elevated temperatures to study the subsequent chemical breakdown.

But what type of product bag should be used in an accelerated aging test?

There are three common options:

1)      Polyethylene — is inexpensive and readily available, but offers a low melting point.

2)      Polyester — offers a higher melting point and can withstand a rigorous aging study, but is more expensive and not widely available.

3)      Aluminum— can be a good option, but is not widely used.  Aluminum is inexpensive and able to reach a higher temperature.  However, aluminum bags are difficult to seal completely (much like foil).

Bag options must be closely considered to ensure a successful aging test. In accelerated aging for medical applications, for instance, we need to determine whether to keep all of the parts in one bag or in separate bags.  It’s best to duplicate the method most commonly used in the real-life environment.

Tell us about your experience with accelerated aging. Check out the Video Learning Center for more information, too!

We all know the importance of sterilization in medical applications and packaging, particularly as surgical procedures become more specialized. Proper sterilization of devices such as catheters, cell culture trays, stents, and implants is critical to ensuring a positive patient outcome.

We thought we’d offer a quick review of sterilization methods:

1)      Steam — This process dates back to the days of Louis Pasteur, who used heat to kill microbes — or “pasteurization” that is still used today to protect perishable products such as milk.

Steam is still a popular sterilization method prized for its simplicity and relatively short processing time.  However, it can cause decay to the polymer, and can destroy surface treatments through water exposure.

2)      Ethylene oxide (EOX)  — is an option for devices that are sensitive to heat and moisture.  EOX changes the surface of the polymer, but it will revert back.  It uses relatively low temperatures for sterilization, but requires a long aeration process after each cycle.

3)   Gamma rays – This is the method we most recommend.  It can be used on many products all at once – it even penetrates boxes.   We also like that it can be used on any plasma-treated surface and preserves the treatment molecules. With gamma, we can increase the dosage accordingly to modify bulk properties.  It is a unique process for cleaning and sterilization.

Which method of sterilization does your team frequently use?

Ultracomp Composite bearings are made using different migratory lubricants. PTFE, Graphite and MOS2 are the traditional lubricants used in these high load, low speed bearings. Historically, MOS2 has been the lubricant of choice in marine environments because of the compatibility of the moly with mating hardware in salt exposure. Graphite would act as a cathodic agent against stainless or other metals when exposed to salt air, salt fog or salt water. Tri Star recommends UC300 with PTFE lubricant as a more universally acceptable material. For dry or wet applications, the PTFE lubricant is an effective agent for low friction lubrication, is compatible with soft mating hardware like aluminum and stainless and has no corrosive effect in the salt environment. Let us know if you have issues with corrosion in your marine bearing applications. We have a solution!

Slide plate bearings provide support and a low coefficient of friction while allowing an object to move (or slide) freely along a supporting surface. They consist of an upper and lower component, and can be used in both guided and free-moving applications.

Slide bearings are engineered to fit anywhere there is the potential or threat of movement, such as bridges, oil pipelines, building footplates, tank farms and petro chemical applications.  For example, the Alaskan pipeline, at roughly 800 miles long, could be subjected to a mile of liquid flow movement(hysteresis) within the structure.  It requires a bearing designed to resist corrosion, temperature extremes and rugged terrain.

Fluorogold slide bearings easily tolerate thermal expansion and liquid flow movement, and hold up well in cold temperatures.  They also absorb vibration and impact, making them a preferred bearing material for use in earthquake zones.

Fluorogold can also be customized to meet exact design requirements and offers outstanding chemical and electrical properties.  They’ve also been tested for and proven resistant to radiation, where neither the bearing strength nor the epoxy bond were impacted by doses as high as 10⁶ rads.

Share your experience with slide bearings.

Our team has seen a spike in interest in slipper seals.

Slipper seals, made from filled PTFE, are designed to act as a low friction interface between a static elastomer expander and the dynamic mating surfaces. i.e shaft or bore. With filled PTFE like our Ultraflon, slipper seals offer exceptional wear life, extrusion resistance, low friction and elimination of stick slip. Slipper seals can be used in both hydraulic and pneumatic applications, lubricated or dry and across a broad temperature range. Since these seals depend on the elastomer for their energizing function, the temperatures will depend on the operating capabilities of that elastomer.

PTFE slipper seals are made in a variety of geometries and cross sections to accommodate the design envelope. There are piston seals, rod seals, wiper seals and a variety of supporting components to make up a complete cylinder design. Tri Star has seal engineers on staff to assist in the design of your slipper seal requirements.

You know the drill – if you have a question, Ask The Experts!

We’ve all been touched by the recent earthquake destruction in Haiti.  And our team is now seeing a renewed interest in surface treatments that can help building materials (like cement) resist seismic activity and sudden impact.

By adding specially treated polyethylene fibers to concrete mixtures, contractors are able to enhance the strength and durability of preformed structures.  With plasma treatment, our team can select the optimum gas chemistry and operating condition to improve the bond strength and interface toughness of ethylene fibers.  Treated fibers have a significantly improved bond strength compared to virgin, non-treated fibers.  With our plasma process, we can enhance the structural integrity of fiber cement mixtures used in buildings, bridges, and other superstructures.