Inside size of the pipe section (the diameter, because the pipe is usually circular):
It is the nominal size of a hose.
Wall thickness:
It is the wall thickness of the hose (the thickness of the single layer in the simple hose, or the complex of under layer, fabric layers and cover in hoses built as a compound). For some applications this data is optional.
Length:
Every kind of hose has a maximum length, due to the characteristics of his construction and to the manufacturer’s production capacity.
Vehicled product:
- Kind and composition in case of oils, gas and fuels, because these terms are too vague.
- Concentration in case of chemical products.
- The maximum and minimum operative temperature.
Pressure:
- Positive pressure (maximum working pressure)
- Vacuum (maximum working depression)
- Burst pressure: it is calculated by multiplying the maximum working pressure by a security factor.
External agents:
- Working temperature of the place of work (most of the times this data is unimportant but, rarely, it is the decisive factor).
- Inclement weather, permanent atmospheric agents (UV rays, humidity, etc.).
- Contact with oils, greases, sea water or aggressive substances.
- Possible mechanical abrasion (i.e. due to the hose traction on abrasive floors, stones, borders, etc. ).
Bending radius:
Minimum radius curvature: this data is often underestimated but indeed it is an important element in determining the lifetime of the flexible hose. Forcing the bending of the hose can produce a stress that risks to reduce significantly its life.
