What is the difference between hose and pipe and can they be replaced in each other's places.

Rigid Metallic Pipe is the most common means of transporting a fluid. Dimensional standards exist for Pipe, but they are referred to in nominal sizes.

Bendable Metallic Tubing is widely used in plumbing, hydraulics, and automotive applications. It is usually based upon the material with a set I.D. and a specified wall thickness. They are generally much thinner than a nominal pipe of the same size. Since they are usually too thin to allow them to be threaded, fittings are usually attached mechanically. This is often achieved by flaring the end of the tubing.

The hydraulic hose fittings are a flexible means of transporting fluids that generally consists of a rubber tube and cover over the number of braided, spiraled, or wrapped plies of reinforcement. Fittings, and their retention methods, vary by application and hose type.

In most cases, the fittings are inserted into the Hydraulic Hose and held in place by clamps to the exterior of the hose. Hose for suction applications incorporates helical support, usually a metallic wire. A plastic hose is also available.

Flexible Rubber or Plastic Tubing is not reinforced and is therefore only suitable for the lowest pressure applications. In some cases the fittings are inserted into the hose and held in place by clamps to the exterior of the tubing, in others, they are merely pushed over the shank/stem of the fitting and held in place by friction.