Fittings and Adaptors are an extremely important hose fitting that extend or terminate hose runs. They are used to connect hoses to various machinery . They may have either male or female threads on one end and the opposite gender on the other end.

When we talk about hose fittings, it means that fittings are used to connect two or more pipes in two ways—either by threads or by slip fit.

Categories of fittings
Fittings can be grouped in one of the following categories:

1. Fittings that extend or terminate hose runs

    • Couplings
    • Adapters
    • Caps and Plugs

2. Fittings that change a hose’s direction

    • Elbows (ells)

3. Fittings that Connect two or more pipes

    • Reducers
    • Bushings
    • Flex couplings
    • Fitting reducers
    • Adapters

Types of threads:

  • Male Threads: In male threads, the threads of the pipe are on the outside. Here, tapered pipe threads like NPT, BSPT etc. are used sealing without gaskets.
  • Female Threads: In female threads, the threads are on the inside. Here too, like male threads, tapered pipe threads are used for sealing.
  • Male Straight Thread: Pipe threads like UNC, UNF, ASME, etc form Male Straight Thread.
  • Female Straight Thread: Straight pipe threads like UNC, UNF, ASME, etc.
  • Flange: Flanges are used to connect fitting, via bolting or welding. There are basically two types of flanges, circular and square.
  • Compression Fitting: This represents compression nut and ferrule to connect to a mating pipe.

Specifications of Size
To determine the usage of a pipe fitting, size is a very important criteria. Here, the main considerations are inside diameter and outside diameter where the inside diameter (ID) has the fitting size matched to the inside diameter of connecting line. The outside diameter (OD) has the fitting size matched to the outside diameter of connecting line. Besides these, sizes also refer to:

  • English / Fractional sizes: Measurement done in inches
  • Metric sizes: Units in mm/cm

Cleaning and care tips of pipe fittings:
In most of the hose fitting systems, contamination is the leading cause of problems. This problem demands for careful installation and regular maintenance so that the fittings can prevent any blockages or system breakdown. Depending on the type of the hose fitting, there are different cleaning methods. For example, one of the caring tips for cleaning hose or tube assembly is that the hose and tube assemblies should be blown out with filtered shop air or flushed and then should be blown out with a solvent which is chemically compatible with the hose material. The ends of the hose / tube assembly should be capped or plugged till the time the assembly is installed.