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HDPE: Best Uses

On the microscopic level, high-density polyethylene has a clean, linear structure that makes the plastic light and strong. It can be manufactured and shipped at low costs, saving companies millions in materials. The simple material is waterproof, UV-resistant, and flexible under pressure, making it the perfect material for numerous uses.

Cost-Effective Uses of HDPE Sheets

Piping

HDPE is commonly recognized as the most cost-effective piping material. Pipe-grade HDPE retains its flexibility at temperatures down to -220˚ Fahrenheit, making it a great candidate to distribute cold liquids underground.

 

What the plastic is infamous for is being tricky to bond. Luckily, bonding techniques have been perfected since HDPE’s invention in the 1930’s. The most cost-effective technique is called electrofusion. Two pipe components are fitted together with a specially designed electrofusion fitting, which is then slowly heated to the melting point. The two pipes then weld into one.

Food Containers

Where HDPE shines brightest is in the consumable goods industry. It’s flexible, strong, and non-leaching. That makes it the perfect container for everything from cereal to ice cream. Best of all, consumers can drop HDPE containers right into the recycling bin when they’re done.

Unlike PVC and polystyrene, HDPE does not leach into water, making it a safe and healthy food container. Not surprisingly, HDPE is the preferred material for baby bottles and disposable cups.

Chemical Bottles

HDPE does not interact with most chemicals. It can safely contain laundry detergent, household cleaner, motor oil, or antifreeze. Adding a pigment to the plastic increases its strength and lengthens the shelf life of the product.

Toys

Being both durable and flexible, HDPE toys usually bounce instead of breaking. The material is safe for infants and toddlers as it does not leech in liquids. Being UV-resistant, HDPE also retains its color for longer than most plastics.

When Not to Use HDPE

This plastic is immune to most chemicals, but will oxidate in acids. For containing acids, we recommend PCTFE. PCTFE is a durable, waterproof plastic with a variety of uses, but is not as cost-effective as HDPE.

Like most plastics, HDPE melts quickly when exposed to open flame. When working with fire, there are two options. One is to treat the plastic with a flame-retardant layer. The other is to use metal instead of plastic.

HDPE is the best budget plastic. That is why it is the material of choice for consumable goods containers everywhere. To see where your company can save, consult Specified Fittings for free.

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Swedge Reducers

Also known as a “swage” reducer, these fittings have become “regulars” here at Specified Fittings. They offer many advantages for a myriad of situations.

When a pipe fails, it’s rarely due to the main body of the pipe run. The flaw usually lies in the details: individual pipe fittings that must facilitate complex changes without causing pressure to impact any one point. A swedge reducer is one of these crucial pipe fittings, which is why we have devoted so much care and attention to designing reliable versions of this product.

A well made and implemented swedge reducer adjusts the diameter of the main pipe run without inhibiting flow. The smooth, rounded structure causes liquids to bounce rather than hit pressure points and create leaks. Our swedge reducers are built with two top priorities: eliminate failure points and maximize flow.

Our Swedge Reducers

swedge reducer

One Piece Swedge Reducers

Each of our swedge reducers is built in one piece and composed of the same material throughout. We use pipe to reduce diameter instead of sheet material, as pipe is smoother and maximizes flow, protecting the rest of the pipeline from becoming damaged. Our swedge reducers are fully rated, adding no additional restrictions to your design. In addition to the practical perks, our single piece swedge reducers are also faster to manufacture, meaning they will be in your hands faster than multi-material fittings of the same variety.

Concentric and Eccentric Swedge Reducers

Our basic concentric design is available up to 63 inches in diameter. Concentric swedge reducers form a straight line in which the center of each section lines up exactly. For a fully optimized flow rate, we recommend an eccentric swedge reducer, which guides the movement of the contents by varying the center of each section. We custom-engineer eccentric swedge reducers to ensure a maximum flow rate for your project. In addition, we keep a stock of 48″x42″, 42″x36″, and 36″x30″ eccentric swedge reducers, designed for optimal flow characteristics.

All our swedge reducers are compliant with the American Water Works Association in all DR’s. A Factory Mutual certification will be included with your purchase upon request. Please contact us to order your custom swedge reducers.

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Custom Backing Rings Pair Perfectly with O-Rings and Flange Adapters

back up rings epoxy coated galvanized steel and stainless steel

A pipe is only as strong as its weakest link. However, an effective backing ring can support and enhance the o-ring, flange adapter, or other fitting it’s paired with. Our pipe fitting design is focused on the big picture: how each piece aligns, how they rely on and support each other to create a reliable, resilient infrastructure. That’s how we got into the custom fittings business. No matter what the ring is backing up, we can custom select the size, shape, and material to get the job done.

Backing Ring Materials

Ductile Iron

This hearty alloy is rich in graphite, making it more resistant to pressure and impact than other grades of cast iron. In the casting process, the graphite forms into spherical nodules, creating a crack-resistant structure.

Ductile iron is the most affordable and most machinable material we suggest for backing rings. We coat each iron fitting in either epoxy or primer to shield against corrosion, though it’s still more vulnerable to moisture than steel. 

It is generally more friction-resistance than steel due to the high graphite content, though this varies depending on the quality of the friction. Consult an expert to determine which material is best for your situation. 

Galvanized Steel

The second-most affordable backing ring option is steel protected from corrosion with a thick zinc coating. If the coating wears away, it still rusts slower than iron. However, galvanized steel doesn’t offer the same level of corrosion resistance as stainless steel. In low-moisture, low-pressure settings, galvanized steel is the best fit. 

Stainless Steel

The most corrosion-resistant iron alloy is formed by introducing chromium to molten steel. It’s well suited for transporting liquids, even salt water and certain acid contents. However, chlorinated water is the enemy of stainless steel and leads to rust.

This in-demand material requires the greatest cost investment but lasts longer in humid conditions.

Pro tip: If two stainless steel fittings are held together under friction, they will eventually weld into one piece. This is something to bear in mind in the long term, as it can complicate repairs.

Don’t see your material on the list? We fabricate and mold new fittings every day. We would love to accept your custom order. Get a quote on your pipe fittings order.