Hydraulic Hose
A hydraulic hose is the flexible connecting component made up of an inner rubber tube, braided or spiral steel reinforcement layers, and an outer protective cover. Single braid types typically have a working pressure of 80-250 bar, while four spiral types are above 350 bar. Every hose also has a minimum bend radius.
The number of reinforcement layers determines both pressure rating and flexibility. As layers increase, the rating rises, the hose stiffens, and the bend radius grows. A hose installed below the minimum radius given in the manufacturer's catalog separates from the inner layer under pressure and bursts early.
- Length allowance: under pressure hose length typically shortens by up to 4% or lengthens by up to 2%; it must not be left taut during installation.
- Chafing: a hose rubbing against the chassis or against another hose wears the outer cover and exposes the reinforcement.
- Life: an aging hose shows cracks in the outer cover, hardening, and traces of moisture at the base of the fitting.
On machines fitted with electronic lever control, hose routing gains extra importance: motor and wiring harness placement must not restrict the hoses' range of movement, and no hose may be stretched or pressed against a sharp corner while the lever goes through full stroke.
Where this term is used: What Is a Hydraulic Lever Retrofit Kit? Definition, Components, Operating Principle