PVC pipes are used in a number of settings for everything from general plumbing and piping to landscaping work and swimming pool related applications.
PVC stands for polyvinyl chloride which is a type of thermoplastic polymer that offers a number of important advantages over other types of piping materials.
PVC piping is lightweight, easy to install, highly durable and does not conduct electricity. Other pipe materials, like copper and stainless steel, are much heavier and more difficult to work with, and because they conduct electricity metal piping may not be advisable in many outdoor applications.
When you weigh all of these factors, it is easy to see why PVC piping is the material of choice for many construction companies.
PVC unions and PVC pipe union connectors are pipe fittings designed to connect two pipes together without the use of a sealant or traditional glued coupling.
The advantage of using PVC pipe unions is that the pipes that are connected using PVC pipe unions can be taken apart and put back together again without the use of specialized tools.
This means that wherever you use a PVC union to connect pipes together these pipes can be disconnected and worked on with relative ease. PVC pipes and PVC pipe unions are preferred by construction companies because they are:
PVC pipe unions come in a variety of shapes and sizes, and are designed to handle all kinds of jobs, from residential plumbing applications such as hooking up washing machines and dryers, to swimming pools and outdoor plumbing applications.
The type of PVC union that will be appropriate to your specific application will depend a great deal on the heat and pressure involved.
In many industrial settings, corrosive liquids and other chemicals that would eat through metal pipe fittings are easily handled by PVC unions. PVC pipes and PVC unions are not always rated for high pressure or heat, so in some industrial applications other materials may needed.
PVC unions for swimming pools are a perfect example of specialize application for a PVC union. PVC unions for swimming pools are designed to make the swimming pool piping easily accessible, while also being highly durable.
Pool chemicals contain compounds that can corrode other types of pipes and pipe fittings. Only specially designed PVC union connectors designed for swimming pools can stand up to these corrosive conditions without becoming corroded and developing leaks.
PVC unions can be used in most instances where two pipes need to be connected. However, there are certain specific settings where construction companies and plumbers prefer to use them.
PVC unions connect two pipes by threading together and do not require the traditional glued sealant coupling method to prevent leakage where the two pipes are joined together.
The threading on PVC unions can be either male or female, with male threading appearing on the outside of the fitting and female threading appearing on the inside of the fitting. This threading is designed to create a perfect seal to prevent leakage in just about any type of piping application, including many applications where liquid may be heated or under pressure, though some limitations do apply.
This makes PVC unions perfect for plumbers, construction companies, swimming pool installation and various industrial and residential maintenance uses.
Jop
on topicReplied byon topic Re: union and coupling
1, "What is the basic difference between coupling and unions?"
Both of these fittings are normally only found or used in 2" (DN50) and smaller screwed or socket-weld piping. The basic difference between a coupling and a union is that a coupling is for joining pipe to pipe or pipe to a swedge. A union is made for joining and disassemble of a part of a piping system (a steam trap or control valve, etc) for maintenance or replacement.
2, "What are the advantages of ones over others?"
The union is a higher cost item than the coupling. When you are just joining pipe you would want to use the lowest cost item. When you need the ability to disassemble the piping for removal of an item then you must use the higher cost union.
3, "Where we use coupling and where we use unions ?"
Use couplings to join pipe in pipe racks. Use unions at steam trap or control valve manifolds for removal of items for repair.
4, "Is there any guidelines or code that specifies where should we use what?"
The use of couplings or unions is not a code issue.
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