In many instances, hardware parts specified by design engineers are considered commodity or generic items — non-proprietary items that are more or less the same, regardless of the supplier. This view may be common to those who order PTFE parts, the synthetic polytetrafluoroethylene that is marketed under the brand name Teflon by the chemical giant DuPont.
Generally speaking, PTFE is well known for its toughness, low coefficient of friction, chemical inertness and other properties that are required in a range of applications. For those industries requiring fluids to be cooled, PTFE seals and gaskets are well suited and can withstand temperatures from cryogenic to 572°F (300°C). However, when it comes to the supply of the PTFE seals and gaskets commonly used in combination with other parts that make up many components and assemblies, there are a number of important factors that specifiers need to consider, according to industry experts.
Those factors include the seal and gasket manufacturer’s capabilities to consistently meet dimensional, material and quality requirements as well as expert in-house engineering assistance. Other important supplier capabilities include the ability to provide reliable just-in-time delivery of orders, and the expertise to offer a range of customized PTFE materials or blends that will better serve a specific type of application.
“Some manufacturers of PTFE gaskets and seals may assume that filling an order is mainly a matter of meeting a customer’s spec and bidding it successfully,” says Rich Stockglausner of Midwest Industrial Sales, Fallon, Mo., a manufacturers’ representative.
“The specifying engineer may not realize it, but there are alternatives to the use of standard PTFE for many applications,” Stockglausner explains. “PTFE can be filled with many different additives. You can put glass fiber in it, or molybdenum, bronze or carbon. Each of those additives can enhance or optimize certain PTFE properties, such as heat or chemical resistance, to provide a more effective seal for certain applications.”
Stockglausner, who has been a manufacturer’s rep for Prolon, Elkhart, Ind., for more than 20 years, adds that it is important for many engineers and purchasing agents to validate their specifications for PTFE seals and gaskets with a supplier that can provide the in-house engineering expertise to customize alternative compounds that are appropriate to a given application.
The ability of a supplier to meet quick turnaround requirements and provide reliable just-in-time deliveries of orders often is a crucial requirement to many manufacturers who use PTFE seals and gaskets.
“Many of these seals and gaskets are relatively inexpensive,” says Matt Walling, a sales representative with manufacturer’s representative Integrated Design Elements, Elkhart, Ind. “Yet it sometimes happens that a shortfall in the supply of a five-cent seal can create downtime on the production of an expensive component or assembly — a catastrophic situation.”
Walling, whose company represents Prolon in Indiana, Michigan and Ohio, says that he can meet quick turnaround requirements on new orders and consistently provide normal deliveries within a six-week period.