This past summer, we had the pleasure of sitting down with engineering.com to talk about non-metal stamped parts production. We talked about a little bit of everything, ranging from non-metal stamp considerations, to custom tooling and production volumes for stamped parts produced in house. Check out the article below, or click here for the full edition.
A part of Everything, with New Process Fibre Company, Inc.
Achilles was a great warrior of ancient Greece and the hero of Homer’s Iliad, but despite his legendary invulnerability, an arrow to the heel led to his downfall. Likewise, something as small as a washer can become the Achilles heel of any design if not considered carefully.
Stamped parts like washers – found in everything from recliners, to kitchen blenders, to cars, and much more – come in a variety of shapes, sizes and materials. With so many options, design engineers might pick the first material and form that meets their basic requirements, but this can lead to a sub-optimal design and problems down the line.
“A lot of engineers pick out the material, dimensions and tolerances they are looking for, but if they pick out a material and it doesn’t work, then they’re kind of stuck,” said Bill Rust, director of sales and marketing at NPF. “We’re here to help.”
Material Considerations for Stamped Parts
Engineers have plenty of good reasons to move away from metal materials and toward non-metallic ones such as thermoplastics, laminates and fibers for stamped parts.
Vulcanized fibre is a light and strong material often comprised of wood pulp, paper and rag material. With good impact and abrasion resistance, as well as high flammability ratings, vulcanized fibre can be used in automotive components or provide electrical insulation, among many applications.
Laminates are composed of various resins and are graded by the National Electrical Manufacturers Association (NEMA) for electrical, mechanical and chemical performance characteristics. They are often suitable for aerospace, automotive, electronics, industrial and petroleum applications.
Thermoplastics are composed of materials such as polyethylene copolymer and homopolymer, acetal copolymer, nylon 6, 6/6 or MDS—and the list goes on. Thermoplastics can be used for a wide range of consumer products and parts.
Good design engineers keep in mind tolerances for factors like heat, and capabilities like lubricant absorption and vibration dampening, when choosing a material.
For example, commodity thermoplastics are poor in electric motor applications, and are likely to melt on the armatures, while thermosets can crack or break in the wrong conditions, Rust said. This doesn’t mean plastics are ineffective or risky materials to use, but that design engineers need to be considerate of their performance requirements when selecting a material.
“Punching plastic is a little different than punching metal,” Rust explained. “Once you punch metal, that size isn’t going to change. Now plastic can pull moisture out of the air a little bit, and it can change the washer’s dimensions by a couple thousandths of an inch, especially if you leave the bag open overnight.”
Custom Design and Manufacturability for Stamped Parts
Just as important as the material type, the thickness and the inner and outer dimensions (ID and OD) of the part must also be determined.
“We make parts to print here,” said Rust. “We need to know tolerances, dimensions and we need to know if this is a washer that they’re trying to retain to a bolt, where it will stay fixed in place without falling off.”
To ensure the tightest fits and tolerances, engineers can send in bolts to be built around and custom-order specific shapes and dimensions.
NPF’s standard tolerances achieve plus or minus ten-thousandths of an inch to even a thousandth on some materials.
Stamped parts can also be designed to meet specific absorption, compression and alignment requirements. For design engineers who aren’t quite sure what they are looking for, NPF can supply samples for inspection and testing.
“A lot of the stuff we do here are speciality washers and so instead of having a round ID or OD, they might have tabs on them or have a hex ID,” Rust said. “We have over 8000 washer dies on the floor. If we don’t have it, we build it and we make all of our own tooling here too.”
Custom Tooling and Production Volumes for Stamped Parts Produced In-House
NPF has an in-house tool room with CAD/CAM and wire EDM capabilities, which allows them to create their own custom tooling.
“If you wanted a part that was in a special shape, like a rectangle, I would only quote a customer for the metal that it costs to build the tool and the die set, and it would be a one-time partial tooling charge,” Rust explained.
NPF holds ownership of the tool and maintains it for the lifetime of the part, which takes the worry and cost of having to inventory, maintain or store the tool off the customer’s shoulders. This practice extends to inventory and storage for excess production volumes to achieve lower costs on the quote.
“If a customer were to place an order for 100,000 parts and only needed 25,000, we would run the whole hundred,” Rust said. “We would keep the extra here on the shelf and release them as the customer needs them.
Working Together with New Process Fibre Company
NPF stamps non-metal materials including vulcanized fibre, acetal, nylon, Teflon, nylon MDS, high- and low-density polyethylene and other speciality materials for industries including consumer goods, aerospace, military, automotive, electronics, plumbing and many more.
With a large inventory and production equipment, NPF tackles production orders of all sizes, without the need for outsourcing, Rust explained.
“We extrude all our own materials,” Rust said. “We also slit our own materials and run the parts out on the press. Making and maintaining our own tooling, we do everything under one roof.”
NPF also manufactures custom discs, end laminations, gaskets, insulators, spacers and tags, as well as washers and parts.
Design engineers in need of assistance finding the right material for their application, can find help in the NPF Material Selection Guide, which includes material characteristics and highlights, common applications, and comparisons.
Working with the right material is crucial for ensuring optimal quality and longevity in stamped parts. But with such a wide range of options available on the market, manufacturers often face a daunting task.
Lexan, a see-through plastic or polycarbonate known for its high durability, has gained popularity across diverse industries; for many companies, choosing this material simplifies the material selection process while allowing for great reliability in highly demanding applications.
The Benefits of Lexan
Choosing Lexan over other materials — such as acrylic, glass, or poly methyl methacrylate (PMMA) or Plexiglas — can offer many advantages. Best used in areas that require a high level of impact resistance, Lexan looks quite similar to glass but provides a much higher degree of durability and resilience, as it is a polycarbonate product. This unique material can transmit up to 90% of visible light and offers the same clarity as glass.
In addition to high durability, Lexan offers the following other features and benefits:
A high level of impact resistance
The ability to handle temperatures up to 240 °F
A low level of flammability
A resistance to acids and other chemicals
Even compared to a similar product, acrylic, Lexan wins out based on its high strength. Lexan is actually 200 times stronger than untempered glass, while acrylic is only up to 8 times stronger. Plus, although acrylic is less costly, it is typically shinier than Lexan and has a higher chance of cracking. However, Lexan does scratch more easily than acrylic despite being more impact-resistant.
Common Lexan Applications
At New Process Fibre, we offer Lexan washers in many different outer diameters, inner diameters, and thicknesses. These versatile fasteners are used in a range of industries, including aerospace, automotive, construction, marine, military and defense, and plumbing.
Well-known for its use in the aerospace sector to construct lightweight, high-strength aircraft windshields, Lexan can also be found in various medical-grade instruments. And in addition to offering superior scratch resistance, it’s also much less likely to shatter than its glass counterparts, making it ideal for harsh, demanding applications.
When choosing the right materials for plumbing applications, water resistance and durability are paramount. While metals have traditionally been used for plumbing components, there are non-metallic alternatives capable of the same level of performance as metals, but are often less expensive. Nylon 6 and PTFE are just two examples.
Nylon 6 is often used for bearings or as wear material. The material is characterized by good wear resistance, high tensile strength, and by its elasticity. The high strength and durability make it an ideal material for replacing metals.
Unlike most metals, Nylon 6 can withstand long term exposure to alkalis, dilute acids, and oxidizing agents.
On the other hand, its elasticity makes it ideal of replacing various plastics, rubbers, and wood. Nylon 6 also has high impact, heat distortion, abrasion, and vibration resistance.
Nylon 6 is a lightweight alternative to metals in plumbing applications. As moisture absorption occurs, the impact strength and energy absorption characteristics of Nylon 6 improve; however, the tensile strength and the stiffness of the material decrease, and some elongation occurs. If these side effects are properly accounted for, Nylon 6 can be used safely for plumbing applications. Furthermore, Nylon 6 can be combined with glass fibers, beads, or carbon fibers to improve its mechanical and thermal
performance. Another thing to keep in mind is that Nylon 6 is softer than one of its counterparts, Nylon 6/6, so Nylon 6 seals better for a male-to-female connection.
Some common uses of Nylon 6 would be in sprinkler heads, showerheads and faucets.
PTFE is a fluorocarbon-based polymer with very high chemical resistance, a large operating temperature range, and high resistance to weathering. Any type of filler that is added to PTFE greatly enhances its mechanical properties. The material is a good thermal and electrical insulator, with a low coefficient of friction; because of these properties, it is often used in brake systems, plumbing applications, HVAC systems, electronics, and many more.
PTFE is ideal for plumbing applications because it is completely impermeable to water or water-containing substances and oil or oil-containing substances. In fact, thread seal tape (also known as plumber’s tape), which is used to seal pipe threads, is made from PTFE. Also, due to PTFE’s ability to withstand high temperatures, utilizing PTFE washers for hot water applications would be ideal then you do not have to worry about a washer deforming or melting and causing leaks. Some common applications where PTFE can be used would be sprinkler heads and faucets.
PTFE is used in many industrial and commercial applications, including cabling, pharmaceutical manufacturing, and semiconductor manufacturing. PTFE (Polytetrafluoroethylene) resin is a paraffin polymer with some or all of the hydrogen atoms replaced with fluorine atoms.
It is classified as a thermoplastic and has a low coefficient of friction, excellent insulating properties, and is chemically inert (to most substances) because of the strength of the carbon-fluorine bonds. PTFE has the third lowest coefficient of friction of all known solid materials – even a gecko cannot stick to it.
PTFE is well known for its versatility; it can withstand very high temperatures and has excellent anti-stick properties (which is why it is so often used to coat pots and pans). It was discovered in 1938 by Dr. Roy J. Plunkett and later commercialized in 1946 by DuPont.
Since then, it has been applied to the chemical industry for vessel linings, seals, spacers, gaskets, and washers; the electrical industry for insulators, tubing, and capacitors; and is FDA-approved for the pharmaceutical, food & beverage, and cosmetic industries. And here, at New Process Fibre, we use PTFE to create many parts, especially PTFE Washers.
Range of Applications
The sheer range of suitable applications for PTFE demonstrates the versatility of the material. PTFEfluoroplastic resins continue to be used in a number of applications, including consumer electronics, tubing for flue gas heat exchangers, food processing equipment, industrial coatings, pharmaceutical processing equipment, and are added to inks, molded gears, seals, and lubricants for added resistance to wear and temperature.
PTFE is a solid at room temperature with a density of 2200 kg/m3. Its melting point is 600 K and it maintains its high strength, toughness, and self-lubrication down to a temperature of 5 K.
As previously mentioned, PTFE is unreactive with most chemicals; only alkali metals or high-temperature aluminum, magnesium, and fluorinating agents will affect PTFE.
When most people think of Nylon, chances are that they think of the type of fabric that you might find in a t-shirt or a pair of gym shorts.
The truth is, however, that nylon is a strong and highly versatile material. It is used in the commercial, industrial, and specialty fields, including the medical industry, plumbing, fire safety sprinkler systems, and many others.
We at New Process Fibre have embraced the material. We use four different types of nylon, mixed and extruded in-house to ensure the highest quality, to produce a robust line of versatile products. New Process Fibre particularly specializes in Nylon washers.
Types of Nylon
We use custom dies—tooled in house—to stamp our products out of four primary types of Nylon. They all have unique properties and benefits.
Nylon 6 is the type found in thread and fabric, but it is also an excellent replacement for metals such as brass, steel, and aluminum. This makes it an excellent application for gears, spacers, washers, and plumbing applications. Nylon 6 has a typical tensile strength of 12,000 psi, flexural strength of 16,000 psi, and is highly resistant to heat, abrasion, water, wear, and vibration.
MDS (Molybdenum Disulfide) filled Nylon is a type of Nylon 6. Design for food grade applications, it is 3A-Dairy, FDA, and USDA compliant. Of all the grades of nylon 6, MDS filled Nylon is the hardest and strongest, which also makes it well suited to applications in wheels, gears, and bearings.
Nylon 6/6 is high viscosity Nylon. Its mechanical strength and high temperature performance are exceptional. It also has electrical and flammability properties that make it uniquely suitable for chemical and electrical applications.
Nylatron®, trademarked by Quadrant, is a blend of Nylon 6/6 and Molybdenum Disulfide. This addition increases the material’s mechanical and thermal properties. Self-lubricating and with a very low surface friction, Nylatron® is perfect for uses that preclude the application of lubricant for operational, safety, or practical reasons.
Why Choose New Process Fibre?
We at New Process Fibre are the most trusted supplier for the largest users of nylon washers for across the globe. In business for almost 90 years, we have built extensive expertise.
Nylon 6, Nylon 6/6, MDS filled Nylon, and Nylatron® are sheet extruded in-house. With full control over raw materials, we are able to provide consistently high quality materials. We maintain a library of more than 8,000 washer dies and can custom tool new dies according to your designs.
With 75 active presses, capable of reaching 400 strokes per minute, stamping Nylon washers with New Process Fibre is cost effective for small batches and high volume orders alike. We can even customize the color of your washers.
Vulcanized fibre is a natural blend of fibrous materials that are heat-treated to create a hard rubber. It is one of the first plastics ever developed and continues to be highly useful for sealing hardware such as plastic washers and gaskets. Fibres that may be incorporated into vulcanized rubber include wood pulp, paper, and fabric materials such as cotton, all of which add strength and toughness to plastic, while still permitting flexibility. In this article, we will explain the many benefits and why you should choose Vulcanized Fibre for your next project.
Vulcanized fibre gets its unique qualities from a chemical reaction between natural fibres and chemical additives such as zinc chloride. When exposed to these parchmentising chemicals, the fibres dissolve slightly, creating a slurry. The slurry is then compressed through a roll or press mechanism at high temperatures to create a bond between materials without adding chemical agents. The thickness of the resultant sheet can be modified to meet manufacturer specifications, and the sheets can be laminated to further increase the material’s thickness.
Vulcanized fibre is versatile and can be custom-shaped using a wide range of fabrication methods, including forming, sawing, cutting, shearing, punching, turning, and milling. Although it is extremely resistant to wear and impact, vulcanized fibre does not perform well in temperatures over 425°F, as the material will burn and break down.
Vulcanized fibre can be formulated in a variety of grades to meet the needs of a broad range of applications. Common grades and uses include:
Commercial-Grade Fibre:Commercial-grade vulcanized fibre is tough and resilient. It is typically available in red, white, black, or gray, and is often used to create gaskets, gears, and washers.
Electrical-Grade Fibre:Electrical-grade vulcanized fibre, also called fish paper, consists of dielectric cotton fibres that can be used as electrical insulators. It is found in a variety of electrical motors for automotive equipment, industrial equipment, and even hand tools and home appliances.
Trunk Fibre:Trunk fibre refers to a grade of vulcanized fibre that is exceptionally hard and abrasion-resistant. Protective skid panels, instrument cases, and steamer trunks are a few examples of products that are made with trunk fibre.
Bone Fibre:Bone fibre is valued for its extreme density and is the hardest vulcanized fibre available. In addition to its mechanical strength, bone fibre is resistant to oils, gasoline, and solvent chemicals. These properties make it particularly useful for tubing, noiseless gears, cut-out fuses, cutting blocks, and thrust washers.
Wood Laminating Fibre:Wood laminating fibre is tough with excellent tensile strength and torsion. It is often used to stabilize and support wood lamination and thin veneers.
Fibre Discs:Vulcanized fibre is an excellent backing material for abrasive sanding, grinding, and polishing discs.
Key Benefits of Vulcanized Fibre
Vulcanized fibre offers a broad array of benefits over other materials, including:
Eco-Friendly:Vulcanized fibre is almost entirely composed of cellulose and doesn’t include artificial binding agents. Compared to other plastics, the manufacturing process is more environmentally friendly and exposes consumers to fewer chemicals.
Highly Versatile:Vulcanized fibre can be formulated for a variety of applications, from automobile components to instrument cases, abrasive discs, and electrical insulation.
Mechanical Benefits: Vulcanized fibre exhibits a high strength-to-weight ratio and is exceptionally machinable. It typically will not break, tear, or splinter during processing.
Chemical Resistance:Vulcanized fibre can withstand exposure to a variety of chemical solvents, oils, and grease without deteriorating.
Cost-Effective:Vulcanized fibre is relatively inexpensive to manufacture and can be customized at minimal cost to enhance desired characteristics.
Vulcanized Fibre Parts and Components From New Process Fibre
At New Process Fibre, we have the in-depth knowledge and experience necessary to provide the perfect fibre components for your needs. For more than 93 years, we have provided stamped vulcanized fibre washers and other components that are critical across industries and sectors.
Whether you need durable washers for industrial applications, a protective instrument case, or durable fish paper, we can create the component you need with the utmost speed and efficiency. To learn more about vulcanized fibre and its many benefits and applications, contact our experts today.
Engineers today know full well of the growing need for specialized and custom materials for stamping. As applications have become more specialized, so too have the materials and configurations available for non-metal stamped products.
With the great array of advancements being made across industries, new applications and processes are increasing the demand for alternatives to traditional metal stamped products. Along with this demand comes the need for new materials in fabrication procedures.
Here are some common options for materials to use in the manufacture of non-metal stamped products.
Vulcanized fibre is also beneficial as a primary or secondary material. It has good strength, high durability, and flexibility. It is easily formable and machinable without splintering or cracking, while also being lightweight and having high tensile strength.
Adding to its versatility is the fact that it is high resistance to solvents and chemicals like oil and grease. The five distinct available grades are commercial, electrical, trunk fibre, bone fibre, and wood laminating, each of which are used for a range of applications across industries.
The term “thermoplastics” is used to refer to any non-metallic polymer, or a plastic that will structurally change when subjected to pressure and high temperature. Thermoplastics become less solid and more gel-like at higher temperatures.
These characteristics make it more malleable and ideal for processes like injection molding, a cost-effective and fast process for high-value thermoplastic components. Along with light machining processes, thermoplastic components can be manufactured to be almost as precise as metal components, but faster and with better consistency.
Thermoset plastics, unlike thermoplastics, have a set strength profile that does not change with temperatures. They are primarily used in high heat applications, such as electrical equipment, insulation, appliances, and printing systems. They are handled similarly to metals and metal alloys during the manufacturing process.
Learn more in New Process Fibre’s Material Selection Guide
New Process Fibre has over 85 years of experience working with alternative methods for metal stamping. That is why we are proud to present our Non-Metallic Material Selection & Properties Guide. Inside, you will find comparison tables, computability charts, and much more detail about the materials presented here. Download your free copy today, and let us know now we can help you with your non-metal stamping needs.
At New Process Fibre we have extensive experience with stamping a variety of washers to meet the needs of our customers in a variety of applications. One particular specialty is our self retaining washers, which we stamp flat with protrusions coming out of the inside diameter to easily grip the screw. This ensures that once the washer is placed on the bolt or screw it will not fall back off. This is especially important in industries, such as the automotive sector that works with the screws upright and wants to make sure the washer stays affixed as it is screwed in.
Typically, we stamp these tabs with triangles or stars, but we can accommodate other designs as well and we can offer hex IDs as well as slit IDs that can offer a bit of give. Often we have customers that apply these self retaining washers as pre-assembled kits ready for installation in their particular application, which can help reduce costs.
At New Process Fibre we house a large selection of conventional and high-speed presses which allow us to offer quick turn around on your high or low volume order of self retaining washers. To learn more about our self retaining washers please visit our website or easily request a quote online.
DID YOU KNOW...
THERMOPLASTIC FORMULAS, SUCH AS NYLON AND TEFLONTM PTFE, PROVIDE A HIGH-PERFORMANCE, LOW-COST ALTERNATIVE TO THE TRADITIONAL METAL WASHERS, GASKETS,AND SPACERS?
Download Material Selection Guide:Nylon and TeflonTM PTFE