Hydraulic Hose Types: Choosing by Construction and Application
Apr 18th 2023
Hydraulic hose selection starts with the job the hose must do. A hose carries pressurized fluid between pumps, valves, cylinders, motors, and other components, but not every hose construction is built for the same pressure, temperature, motion, or fluid.
Most hydraulic hoses share three basic layers: an inner tube that carries the fluid, reinforcement that supports pressure, and an outer cover that protects the assembly from abrasion, weather, and handling damage.
SAE Standard Hose Families
SAE hydraulic hose standards describe construction and performance requirements for different hose families. The standard helps identify the inner tube material, reinforcement style, cover material, and pressure capability.
Common SAE hose families run across many constructions, from low-pressure return hose to medium-pressure thermoplastic hose and heavy-duty spiral-wire hose. A buyer should not choose by the SAE number alone, but it is an important starting point.
Low-Pressure Hose
Low-pressure hydraulic hose is commonly used for return lines, suction or vacuum service, anti-static lines, and other circuits that do not carry high working pressure.
SAE 100R4 and 100R6 are common examples in low-pressure categories. These hoses may use textile braid reinforcement, and some constructions include a spiral wire for vacuum or suction support. They are often compact and easier to route than heavier high-pressure hose.
Thermoplastic Hydraulic Hose
Thermoplastic hydraulic hose uses a polymer tube rather than a conventional rubber tube. For the same inside diameter, thermoplastic construction can provide flexibility, durability, and strong low-temperature performance.
SAE 100R7, R8, and R18 are common thermoplastic hose families. They can be used in medium-pressure hydraulic circuits, machine tools, construction equipment, hydraulic lifts, and applications that need cleaner routing or non-conductive options.
Spiral Steel Wire Hose
Spiral-wire hydraulic hose is used for high-pressure and severe-duty applications where pressure spikes, flexing, and heavy equipment loads are expected. Agriculture, logging, mining, and heavy mobile machinery often need this type of hose.
Hose such as SAE 100R13 uses multiple layers of spiral reinforcement, often with layers laid in opposite directions for strength and stability. The result is strong pressure capability, but the hose may be less flexible than lighter braided constructions.
Using STAMP to Select the Hose
STAMP is a useful selection method: Size, Temperature, Application, Media, and Pressure. Size starts with hose inside diameter because ID affects flow velocity. Dash sizing is often used, where the dash number relates to sixteenths of an inch.
Temperature includes both the hydraulic fluid and the surrounding environment. The hose tube and cover must remain within their rated range so they do not harden, crack, soften, or shed debris into the system.
Application covers routing, movement, abrasion, exposure, and whether the hose must pass through tight spaces. Media means the fluid being carried; the inner tube and any seals must be compatible with that fluid. Pressure includes working pressure and expected surges.
The correct hose type is the one that matches all of those conditions, not simply the strongest or thickest hose on the shelf. Hose construction, fittings, crimp data, bend radius, and routing should be treated as one assembly decision.