The HDPE resin is heated and extruded through a "Die (Cutting)" die, which determines the diameter of the pipe. Pipe wall thickness is determined by a combination of die size, screw speed, and drag tractor speed. Polyethylene pipe is usually black in color due to the addition of 3-5% carbon black to the transparent polyethylene material. The addition of carbon black creates a UV light resistant product. There are other colors available, but they are less common. Colored or striped HDPE pipe is typically 90-95% black material, with only a 5% layer of color or stripe on the outside.

The HDPE pipe extrusion process is detailed below:

The polyethylene raw material is drawn from a silo into the hopper dryer, which removes moisture from the granules. A vacuum pump then pushes it into the blender, where it is heated with a barrel heater. The PE material melts at around 180 degrees Celsius (356°F), allowing it to be fed through a mold/die, which gives the molten material a circular shape. After passing through the die, the newly formed pipe quickly enters cooling tanks, which immerse or spray water on the outside of the pipe, each of which reduces the temperature of the pipe by 10 to 20 degrees. Because polyethylene has a high specific heat capacity, the pipe must be cooled in stages to prevent it from deforming, and by the time it reaches the "pull tractor" it is hard enough to be pulled gently. A laser or powder printer prints the size, type, date, and manufacturer's name on the side of the pipe. It is then cut with a cutting saw, either into lengths of 3, 6, 12, 24 metres, or wound to 50, 100, 200 m lengths on a winder.

A different die is used for striped HDPE pipe, which has small channels that the colored material passes through, just before it is pushed through the die. This means that the strips are formed as an integral part of the pipe and are not likely to separate from the main body of the pipe. Co-extruded or co-extruded HDPE pipe has a second extrusion screw that adds an extra layer of color around the black HDPE pipe, allowing the pipe to be colored on the outside for identification or thermal cooling requirements.

An example of the durability of HDPE pipe is that used for the Ocean Cleanup project, which is being dumped into the ocean to clean up the Great Pacific Garbage Patch.[7]​.

Although HDPE pipes are often estimated to last 50 years, in fact they are more likely to have a life expectancy of 100 years.[5]​.

The HDPE resin is heated and extruded through a "Die (Cutting)" die, which determines the diameter of the pipe. Pipe wall thickness is determined by a combination of die size, screw speed, and drag tractor speed. Polyethylene pipe is usually black in color due to the addition of 3-5% carbon black to the transparent polyethylene material. The addition of carbon black creates a UV light resistant product. There are other colors available, but they are less common. Colored or striped HDPE pipe is typically 90-95% black material, with only a 5% layer of color or stripe on the outside.

The HDPE pipe extrusion process is detailed below:

The polyethylene raw material is drawn from a silo into the hopper dryer, which removes moisture from the granules. A vacuum pump then pushes it into the blender, where it is heated with a barrel heater. The PE material melts at around 180 degrees Celsius (356°F), allowing it to be fed through a mold/die, which gives the molten material a circular shape. After passing through the die, the newly formed pipe quickly enters cooling tanks, which immerse or spray water on the outside of the pipe, each of which reduces the temperature of the pipe by 10 to 20 degrees. Because polyethylene has a high specific heat capacity, the pipe must be cooled in stages to prevent it from deforming, and by the time it reaches the "pull tractor" it is hard enough to be pulled gently. A laser or powder printer prints the size, type, date, and manufacturer's name on the side of the pipe. It is then cut with a cutting saw, either into lengths of 3, 6, 12, 24 metres, or wound to 50, 100, 200 m lengths on a winder.

A different die is used for striped HDPE pipe, which has small channels that the colored material passes through, just before it is pushed through the die. This means that the strips are formed as an integral part of the pipe and are not likely to separate from the main body of the pipe. Co-extruded or co-extruded HDPE pipe has a second extrusion screw that adds an extra layer of color around the black HDPE pipe, allowing the pipe to be colored on the outside for identification or thermal cooling requirements.

An example of the durability of HDPE pipe is that used for the Ocean Cleanup project, which is being dumped into the ocean to clean up the Great Pacific Garbage Patch.[7]​.

Although HDPE pipes are often estimated to last 50 years, in fact they are more likely to have a life expectancy of 100 years.[5]​.