Heated Hose Design Parameters

Overall hose length consideration example.

To help us design a heated hose assembly for your particular application, the following design parameters must be determined.

1. Size

The diameter of the connections to which the assembly will be installed is needed to provide a proper fit. This information is required.

2. Temperature

As the temperature to which the assembly is exposed (internally and externally) increases, the strength of the assembly’s components decreases. Also, the coldest temperature to which the hose will be exposed can affect the assembly procedure and/or fitting materials. If you do not provide this information, it will be assumed that the temperatures are 70° F.

3. Application

This refers to the configuration in which the assembly is installed. This includes both the dimensions of the assembly, as well as the details of any movement that the assembly will experience. This information is necessary to determine assembly length and required flexibility.

4. Media

Identify all chemicals to which the assembly will be exposed, both internally and externally. This is important since you must be sure the assembly’s components are chemically compatible with the media going through the hose, as well as the environment in which the hose is to be installed. If no media is given, it will be assumed that both the media and the external environment are compatible with all of the available materials for each component.

5. Pressure

Identify the internal pressure to which the assembly will be exposed. Also, determine if the pressure is constant or if there are cycles or spikes. This information is important to determine if the assembly is strong enough for the application. If no pressure is given it will be assumed that the pressure is low and there are no pressure surges or spikes.

6. End Fittings

Identify the necessary end fittings. This is required since fittings for the assembly must be chosen to properly fit the mating connections.

7. Dynamics

Identify the velocity at which the media will flow through the assembly. Since corrugated metal hose does not have a smooth interior, rapid media flow can create a resonant frequency that will cause the hose to vibrate and prematurely fail. If no velocity is given, it will be assumed that the velocity is not fast enough to affect the assembly’s performance.

Assembly Components

The various components that make up a heated hose assembly, and what information engineering will need in order to make a hose assembly for your application.

In order to produce an assembly, the fabricator will need answers to the following five questions:

  1. Hose (type, allow & size)
  2. Fittings (type, alloy & size for each end)
  3. Length (either the overall length or live length)
  4. Jacket (depending on your environment)
  5. Leads ( power lead & thermocouple location)