Types of Plastic Water Pipes and Tubing

Types of plastic water pipes are classified by their material. PEX stands for cross-linked polyethylene, PVC stands for polyvinyl chloride, and LLDPE stands for linear low-density polyethylene. Choosing the right tubing material depends on its chemical compatibility, temperature rating, and pressure of the fluid from your application. John Woodard, our Master Water Specialist, discusses features of common types of plastic water pipes and tubing and where to use them. 

Types of Plastic Water Pipes

PEX ⌄	LLDPE ⌄	Santoprene ⌄	Silicone ⌄	PVC ⌄	Polyurethane ⌄	Polypropylene ⌄

PEX Tubing

What is PEX tubing? 

PEX tubing is made of cross-linked polyethylene for extra strength and is suited for hot or cold drinking water. PEX tubing typically comes in larger diameters, from 1/2" to 1 1/2". The size is based on the inner diameter (ID) of the tubing, also called nominal or CTS (copper tube size).

Where to use PEX tubing: Many builders use PEX tubing for household plumbing. The entire distribution system, from the service line in the street to the faucet in your bathroom, is constructed with PEX pipe.

PEX is manufactured without an oxygen barrier and may be used in radiant heat applications where there are no ferrous (metal/iron) components.

Here's how to cut a PEX pipe.

PEX Pipe Sizes

PEX is primarily used in 1/2" or larger. It can be installed with crimp fittings or quick-connect fittings.

PEX pipe temperature information

PEX's strength at temperatures ranging from below freezing up to 180 degrees Fahrenheit makes it an ideal tubing material for hot and cold water plumbing systems, hydronic radiant heating systems, snow melting applications, and even ice rinks and refrigeration warehouses. PEX is highly resistant to chemicals found in the plumbing environment.

Note: PEX is designed for indoor and buried applications only. PEX tubing should not be exposed to direct sunlight for an extended period of time.

Linear Low-Density Polyethylene Tubing

Linear low-density polyethylene (LLDPE) tubing is perfect for potable water, food and beverage, and pneumatic compressed air applications. 

What is polyethylene tubing?

Polyethylene tubing offers excellent pressure and temperature ratings and has outstanding resistance to environmental stress cracking.  LLDPE or linear low-density polyethylene is the most common type of plastic water pipe. LLDPE is more robust than traditional low or medium density polyethylene and is recommended for use with cold and intermittent hot water.

Where to use polyethylene tubing: This tubing connects water filters, countertop faucets, ice machines, and under-sink water filters. A polyethylene pipe is sturdy but flexes a little to protect it from bumps under the counter. The tubing is manufactured with FDA approved materials and is NSF Standard 51 and 61 certified.

LLDPE tubing is designed for use with all standard fittings and point-of-use drinking water systems. It's made from non-contaminating materials and provides the benefits of a wide range of temperature and pressure suitability and broad chemical compatibility. LLDPE is commonly used in water purification, water conditioners, ice makers, and misting systems.

LLDPE Tubing Sizes

Santoprene Tubing

What is santoprene tubing?

Santoprene tubing, also known as thermoplastic rubber tubing, offers good mechanical properties under a wide range of operating temperatures. Santoprene works well with hot water applications. If you're looking to buy a hot water tank to go under your sink, it may require a santoprene tube to carry hot water up to the faucet up on top. Santoprene tubing is highly durable and resistant to fatigue, ozone, ultraviolet, acids, alkalies, water, and most oils and lubricants. 

Features:

• All sizes are 73A food grade
• Features flex fatigue performance w/extended life cycle
• Provides material cost savings vs. silicone tubing
• Offers good chemical resistance and drug compatibility

Santoprene Tubing Sizes

Silicone Tubing

Silicone tubing is extremely pliable and elastic, and it is not altered by the effects of weather. It generally exhibits inertness toward UV radiation and ozone, making it an excellent choice for electrical applications. Silicone is a very pliable soft material used frequently in the medical industry because of its resistance to many chemicals.  

What is silicone tubing?

Silicone tubing has long been used in the medical field because it is clean and nontoxic. Its flexibility allows it to fit in tight spaces. Silicone is also resistant to high temperatures, which has enabled its use in applications where plastic or rubber tubing cannot handle the heat. This tubing is approved by the FDA, making it suitable for food service applications. This plastic tubing also comes as a braided product, which provides additional strength for high-pressure applications.

Uses for silicone tubing:

• Adhesive lines
• Aerospace
• Appliances
• Automotive
• Beverage and dairy
• Blood and biological fluid
• Cell culturing
• Insulation sleeving
• Liquid resin feeds
• Pharmaceuticals
• Surgical drains
• Chemical transfer
• Clean rooms
• Computers
• Deionized water
• Dialysis
• Duplicating equipment
• Fermenter lines
• IV administration
• Medical and dental
• Protective jacketing
• Thermal protection
• Hot fill lines
• Food handling
• Laboratory
• Resin feeds
• Stirring vessels
• Viscous material handling
• Vaccine transfer
• Laboratory
• Peristaltic pumps
• Sterile bottle filling

Silcon® Silicone Tubing

Silcon® silicone is popular for its flexibility and resistance to extreme temperatures. Silcon silicone is also known for its electrical properties and its ability to self-extinguish, making it an excellent choice for appliances and computers. Silicone tubing is often used for high-purity applications in the medical and pharmaceutical industry.

Features:

• Made from FDA-sanctioned ingredients
• Able to resist extreme temperature variations: -100º F to 500º F
• Translucent natural color for visual contact with the flow
• Resilient, stretchable, and resistant to compression set
• Odorless, tasteless, and inert
• Good electrical and weather-ability properties
• Resists UV, ozone, gases, and moisture
• Certified to NSF Standard 51 for food equipment materials

Peroxide-cured silcon contains no sulfur or other acid-producing chemicals, which eliminates the possibility of corrosion, staining, or deterioration. Silcon also resists ozone and ultraviolet light over long periods of time.

Don't implant silcon in continuous steam applications. Silcon may be low-pressure steam sterilized in-line or autoclaved at up to 250º F in a normal autoclave cycle. However, if it's exposed to repeated steam sterilization or long-term high temperature or pressure, silicone will eventually relax and become gummy.

Uses for silcon silicon tubing:

• Appliances
• Beverage service
• Computers
• Deionized water transfer
• Duplicating equipment
• Foodservice
• Gaskets, seals and O-rings
• Hot water feeds
• Insulation sleeving
• Laboratory
• Medical and dental
• Peristaltic pumps
• Portable gravity water filters
• Thermal protection

Use caution when selecting fittings and clamps for silicone tubing. Sharp barbed fittings or unlined metal clamps can tear into the tubing wall.

Medical Grade Silicone Tubing

Silicone medical grade tubing is platinum-cured for ultimate purity. Silcon medical grade tubing elastomer meets USP Class VI requirements. Medical grade silicone is manufactured under strict Good Manufacturing Practices (GMP) in a controlled environment. Silcon tubing used for medical applications is reusable and withstands repeated sterilization. 

Features:

• Made from FDA-sanctioned ingredients
• Able to resist extreme temperature variations: -100º F to 400º F
• Translucent natural color for visual contact with the flow
• Resilient, stretchable, and resistant to compression set
• Odorless, tasteless, and inert
• Good electrical and weather-ability properties
• Resists UV, ozone, gases, and moisture
• Certified to NSF Standard 51 for food equipment materials
• Medical Silicone Tubing

Medical grade silicone tubing's surface properties resist sticking and encrustation and prevents bacteria growth. Silcon tubing is soft and pliable and contains no plasticizers that could leach out and cause water flow contamination or tube hardening. Silcon may be low-pressure steam sterilized in-line or autoclaved at up to 250º F in a normal autoclaving cycle. However, if it's exposed to repeated steam sterilization or long-term high temperature or pressure, silicone will eventually relax and become gummy.

Uses for medical grade tubing:

• Biomedical
• Blood and fluid handling
• Dialysis
• Food and beverage
• Health and beauty
• IV administration
• Laboratory uses
• Personal care
• Pharmaceutical processing
• Surgical feeds and drains

Silbrade Braid Reinforced Silicone Hose

Silbrade® reinforced silicone tubing is an open mesh polyester braiding incorporated within the walls of silicone tubing. Silbrade enables silicone tubing to handle increased pressure applications and offers exceptional resistance to extreme temperatures. Silbrade also allows excellent bend radii and permits installation in restricted spaces with impeding flow.

Features:

• Made from FDA-sanctioned ingredients
• Able to resist extreme temperature variations: -80º F to 350º F
• Translucent natural color for visual contact with the flow
• Resilient, stretchable, and resistant to compression set
• Odorless, tasteless, and inert
• Resists UV, ozone, gases, and moisture
• Certified to NSF Standard 51 for food equipment materials

Uses for silbrade® silicone hoses:

• Adhesive lines
• Beverage service
• Bottle filling
• Chemical feed
• Deionizing water transfer
• Fermenter lines
• Hot fill lines
• Food handling
• Laboratory
• Resin feeds
• Stirring vessels
• Peristaltic pumps
• Viscous material handling

PVC Tubing

What is PVC tubing?

PVC is a softer type of tubing Also great chemical resistance like silicone. Braided PVC tubing is often used in the food industry to supply water to a beverage dispenser. 

Clear PVC Tubing

Clear PVC hoses are abrasion-resistant tube and will not impart taste or odor. Parker Nexbraid series 125 PVC tubing is an excellent choice for pneumatics, flexible conduit, harness, and light vacuum applications. This tubing is made from FDA and NSF listed materials and can be used for beverages and potable water, dry abrasive materials such as grains, granules, pellets and powders, non-fatty and non-oily foods, and sanitary products.

Clear Steel Wire Reinforced PVC Suction Hose

NewAge Industries Vardex® clear steel wire reinforced PVC suction hose is constructed out of non-toxic, corrosion-resistant PVC, specifically suited for transporting chemicals in areas with sharp bends or tight turns. Its bend radius is approximately four times its inner diameter, making it perfect for applications where resistance to crushing and kinking is important. Manufacturers construct this hose with a technique that permits Vardex full vacuum capabilities (29.9 in./Hg.) for all sizes without hose collapse.

Features:

• Made from non-toxic ingredients conforming to FDA standards
• Handles pressure & full vacuum (29.9 in./Hg.) applications
• Spiral steel wire reinforcement incorporated within the wall of flexible PVC tubing
• Glass-like clarity with mirror-smooth surfaces provide outstanding visual flow characteristics
• Lightweight (compared to rubber hoses) yet tough and abrasion resistant
• Kink and crush resistant

Uses steel wire PVC:

• Chemical transfer
• Coolant lines
• Environmental suit air feed
• Floor cleaning equipment
• Food & beverage lines
• Shop air supply
• Spray systems
• Vacuum lines
• Water feeds

Clear Polyurethane Tubing

Clear polyurethane tubing is made from non-toxic ingredients and conforms to FDA standards for use with wet and fatty foods. It's transparent, flexible, and resistant to weathering, tearing, impact, radiation and abrasion. This ether-based tubing contains no plasticizer that could cause flow contamination or hardening of the tubing.

Features:

• Can be heat sealed, coiled, fabricated, or bonded
• Contains no plasticizer which could cause flow contamination or tube hardening
• Resistant to oils, greases, and fuels
• Approved by FDA, NSF-61

Uses for clear polyurethane:

• Cable jacketing
• Clean liquids
• Computer manufacture
• Fuel lines (small motor)
• Gases
• Granular materials
• Grease and lubrication lines
• Instrumentation
• Insulation sleeves
• Internal contamination fluids
• Metering pumps
• Nuclear power facilities
• Pressure measuring devices
• Robotics
• Slurry transfer
• Vacuum lines
• Washers and bumpers

Polypropylene Tubing

1/2" OD polypropylene tubing is ideal for the transfer of hot liquids or gases. It is durable and heat resistant in applications high temperature and pressure are present. This NSF 51 certified tubing is normally recommended for vacuum systems. Polypropylene resists acids and alkalis but has poor resistance to aromatic, aliphatic and chlorinated solvents.

Once you find the right material, determine what size tubing you need. Learn how to buy the right fittings based on pipe dimensions. You also need to determine what fitting matches your pipe thread size.

Related products:

• All softer tubing, like silicone and PVC, connect with a barb that goes inside of the inner diameter of the tube and holds that tubing on to the fitting.
• Other types of plastic water pipes connect with quick-connect, compression, and a variety of other fittings. 
• To cut a PEX pipe, you'll need a pipe cutter.