Different pipes for different purposes
PEX pipes are made of cross linked polyethylene polymer. They are light in weight and very easy to handle. They can be spooled to carry or store which reduce the cost of transportation. Pex has proved to be more economical in every way. People have adopted the new product happily as it reduces the cost of plumbing as well as maintenance. The added facility of continuous lengths of pipes can be obtained so it reduces the requirement to join lengths of pipes to make one long pipe. They serve a multitude of purposes and there are specific pipes manufactured to suit the various purposes.
Although people use the words PEX pipe and tube as inter changeable words there is a slight difference. The material used is same but the dimensions are different. The inner diameter is fixed and the thickness may vary as per the requirement. The tubes have a fixed outer diameter and come only in standard thickness. The general color of the PEX pipes is natural; color is added to get pipes in red, blue, black or white. The red and blue pipes are used in homes to distinguish between the hot and cold water. The specifications and the standards that they meet are printed on the pipe to make it convenient for the buyer.
Sometimes these pipes are used to transport material which have to be protected from oxygen so there are pipes which can bar the seeping of oxygen. The pipes are coated with a polymer on the outer surface of the pipe. At times the polymer sheet is placed between the layers of the PEX material and sandwiched to make it oxygen resistant. The material used to make the oxygen barring sheet is a polymer film called ethyl vinyl alcohol co-polymer. The same material is used by the food industry to keep oxygen from attacking the food.
The other method used to bar oxygen is the placement of aluminum sheet in between the sheets of the pex sheets. The aluminum sheet acts as a barrier for the oxygen. These pipes are called the multilayer pipe or the composite plastic aluminum pipe. Although aluminum is embedded the basic characteristics of the PEX pipe is retained. It can be bent and used as the normal pipe can be used. There is a slight difference in the flexibility of the pipe. It would shrink or expand less with variation in the temperature. The cost of these pipes is slightly higher than the normal pipes.