Monthly Archives: January 2016

Designing with Thermoplastics in Pump & Valve Components

Why are thermoplastics (engineering plastics) replacing metals and becoming a popular option for machined parts? To answer this question we’ve got a few blog posts that look at different aspects of why people are saying yes to engineering plastics. Pumps and valves have been around for about as long as humans have been constructing things to make life easier. Today pumps and valves occupy places in nearly every industry from medical, laboratory and testing equipment, to oil and gas, agriculture, transportation, buildings and more.

Designing pump and valve components from thermoplastics has the benefit of being made from materials that are corrosion resistant. But, even plastics withstand varying physical elements in different ways so it’s important to understand how plastics can also be affected by the physical elements they will be exposed to. The chart below looks at some of the most common plastic resins and gives a general guideline for how they stand up to potential corrosive elements.


Chart of Chemical Resistance for Common Polymer Resins / Thermoplastics


CHEMICAL RESISTANCE POLYMER RESINSA Deeper Look at Corrosion and What it Is
Corrosion is the deterioration of a material and its physical properties, Corrosion of a material occurs because of an undesirable reaction with its surrounding environment. In valve applications chemicals may attack the exterior as well as the interior surfaces. As you can see from the chart above both acids and alkalis will attack some materials. Corrosion begins with pitting that is not even visible to the eye. But once it begins corrosion continues to grow and eventually it leads to part failure. But even before creating a leak, pits increase turbulence which affects performance.

Corrosion is caused by more than just hazardous chemicals. As you can see from the chart of common thermoplastics above, sometimes an apparently benign fluid can react, as when sea water flows over brass.

How Can Corrosion of Machined Parts Be Stopped?

The best and most cost-effective way of controlling corrosion is preventing it. Studies have shown that an overall cost savings of 40% can be achieved when corrosion is prevented rather than treated. Prevention entails selecting an engineering plastic that will work best with the media being transported through the device. Whether you are using metals or thermoplastics, all environmental factors should be considered, including cleaning agents and things that might not be thought of as highly corrosive. In some cases a sacrificial layer could be used but these will have a finite life, and as the name implies the sacrificial material needs to be closely monitored and it will still require downtime to apply a new sacrificial layer.

Many customers that replace metal valves and gaskets with engineered plastics often note a number of positive benefits even if the initial part costs more.

  • Reduced maintenance
  • Reduced Downtime 
  • Reduced incidence of part failure
  • Longer lasting parts
  • Overall cost savings
  • Smooth surfaces allow for increased velocity and precision control of flow

Customers with ultra-high purity such as medical device, food processing, or water treatment applications to name a few, require very smooth interior surfaces with absolutely no place for contamination to lurk and with no risk of particles breaking free and joining the fluid. Even microscopic pitting can be cause for parts to be replaced because the pitting can allow for bacteria contamination. Once pitting occurs it is virtually impossible to clean a valve or gasket to the high standards required for high purity applications.

The highly smooth surfaces that can be achieved with machined thermoplastic materials can also reduce turbulence in fluids being transported. This allows for fluids to flow at higher velocities and allows for precision control of pumps.

Beginning with careful material selection, research and talking to experienced plastic professionals can lead to designing pump and valve components that can improve performance and increase life from day-to-day to your most demanding applications.

Do you have questions about material selection for seals and valve gaskets like:

What are the lower cost and lighter weight options to metal-to-metal sealing?

We are having thermal degradation issues with plastics in valve components, can we improve this?

Our seals and gaskets have to withstand higher and higher operating pressure. What  materials have higher compressive capabilities and creep resistance?

These are all questions I am able to assist you with. Feel free to contact me at the information below.



Montague-Sml-DSC_0304Kendall Montague
Industry Segment Manager

thyssenkrupp Materials NA
AIN Plastics Division


Kendall Montague is a veteran of the plastics industry with 16+ years experience working with OEM and MRO engineers assisting in developing thermoplastics material selection as well as custom design and fabrication using CNC equipment.

Active Member with the Energy & Polymer Group – Houston

AIN Plastics Renews with DuPont for Vespel

In 1993, AIN Plastics was appointed E.I. DuPont’s first national distributor of Vespel® polyamide stock shapes, one of the industries most sophisticated materials. This month thyssenkrupp Materials NA AIN Plastics Division is proud to be continuing its relationship with DuPont, and now DOW with its renewal of the distribution agreement to continue as the Authorized Vespel® Stock Shapes Distributor for the Eastern half of the US and Canada. DuPont™ Vespel® continues to be the material of choice for high performance applications and it remains unmatched for its unique combination of properties achieved through DuPont’s proprietary Isostatic Molding Process. As for AIN Plastics, we have finalized and agreed upon an extension of our Distribution Agreement with DuPont.

Changes in the Plastics Business make Front page news!

As the Sales and Marketing Manager for DuPont™ Vespel® Authentic Shapes for thyssenkrupp Materials NA AIN Plastics Division, I get to live and breathe High Performance Plastics.  DuPont™, who invented DuPont™ Vespel® as well as Teflon®, Delrin®, and a multitude of other Engineering Resins known throughout the world, has been a partner with thyssenKrupp MAterials AIN Plastics Division for over 30 years. Through that time frame we

Space ShuttleFlying In The Sky. 3D Scene.

have seen 5 US presidents, the era of the space shuttle, the invention of the Internet, and mobile phones going from the size of a shoebox to being a must-have business and personal communication and entertainment device that fits in our pocket.  Through all of this, steady as a rock, DuPont was DuPont.  Always a technical leader, always an innovation resource in engineering plastics industry, DuPont materials and DuPont™ Vespel® are often considered the Gold Standard by which other plastics were measured.  So recently iStock_000060987992_Doublewhen the announcement that DuPont is merging with Dow was made it was an unexpected piece of news. But it is news that I look to as exciting.

What makes this announced merger of DuPont and DOW so exciting is the potential it brings to the table for more innovation.  This acquisition is called a “merger of equals” for good reason. Dow has a long history of technical advances in the Polyethylene business as well as other performance plastic families.  Meanwhile DuPont has been the leader in nylons and acetals stock shapes and injection molding materials.  I can only imagine what kind of new products these two technical companies and their extensive teams will dream up once they are together.

We will of course be watching as this proposed merger makes it’s way through all the legal channels and we look forward to the future with the new combined DOW DuPont. Feel free to contact us if you have any questions and I will be more than happy to help. To give you more information I’ve added a few links below to new and press releases about the DOW DuPont merger.


Press Release Regarding the DOW / DuPont Merger

The Washington Post Takes a look at DOW DuPont Merger and Company histories

USA Today DOW DuPont Merger News and Video


Photo-Hanson-DSC_0295Paul Hanson

Industry Segment Manager, DuPont™ Vespel®
thyssenkrupp Materials NA
AIN Plastics Division

Blog contributor Paul Hanson has been active in the Sales and Marketing of Engineering Plastics for over 20 years.  From Aerospace to Semicon, Paul’s expertise has been valuable to his customers and a key resource in specifying High Performance materials in demanding applications.




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