1. High pressure/transmission
2. Distribution systems
3. Distribution systems PE fittings
4. Water pipeline fittings
A fitting is used in pipe plumbing systems to connect straight pipe or tubing sections, to adapt to different sizes or shapes, and for other purposes, such as regulating or measuring fluid flow. The term plumbing is generally used to describe conveyance of water, gas, or liquid waste in ordinary domestic or commercial environments, whereas piping is often used to describe high-performance (e.g. high pressure, high flow, high temperature, hazardous materials) conveyance of fluids in specialized applications. The term tubing is sometimes used for lighter-weight piping, especially types that are flexible enough to be supplied in coiled form.
Fittings require money, time, materials, and tools to install, so they are a non-trivial part of piping and plumbing systems. Valves are technically fittings, but are usually discussed separately.
Standards:
There are certain standard codes that need to be followed while designing or manufacturing any piping system. Organizations that promulgate piping standards include:
ASME – The American Society of Mechanical Engineers
A112.19.1 Enamelled cast iron and enamelled steel plumbing fixtures Standard, American Society of Mechanical Engineers (ASME)
A112.19.2 Ceramic plumbing fixtures Standard, American Society of Mechanical Engineers (ASME)
ASTM – American Society for Testing and Materials
API – American Petroleum Institute
AWS – American Welding Society
AWWA – American Water Works Association
MSS – Manufacturers’ Standardization Society
ANSI – American National Standards Institute
NFPA – National Fire Protection Association
EJMA – Expansion Joint Manufacturers Association
CGA – Compressed Gas Association
For example, pipes need to conform to the dimensional requirements of :
ASME B36.10M – Welded and Seamless Wrought Steel Pipe
ASME B36.19M – Stainless Steel Pipe
ASME B31.3 2008 – Process Piping
ASME B31.4 XXXX – Power Piping
The B31.3 / B31.4 code has requirements for piping found in petroleum refineries; chemical, pharmaceutical, textile, paper, semiconductor, and cryogenic plants; and related processing plants and terminals. This code specifies requirements for materials and components, design, fabrication, assembly, erection, examination, inspection, and testing of piping. This Code is applicable to piping for all fluids including:
1. Raw, Intermediate and finished chemicals
2. Petroleum products
3. Gas, Steam, Air and Water
4. Fluidized solids
5. Refrigerants
6. Cryogenic fluids