Hydraulic hose construction consists of three plies from the view of the section, the inner tube is in touch of hydraulic fluid, which is made of synthetic rubber, and the middle layer is hose reinforcement which is the source of how hydraulic hose can withstand high pressure. The outer cover is also made of synthetic rubber, which resists corrosion from the outside and keeps the inner layer out of damage. This time, we will concentrate on the hydraulic hose reinforcement and talk about its effect on the hydraulic hose.
How important is the hydraulic hose reinforcement?
The working pressure and burst pressure are both crucial parameters of hydraulic hose, the safety factor is the ratio of them via B.P. divided by W.P., these parameters are all shaped by hydraulic hose reinforcement.
The working pressure is the top limit of practical pressure in a hydraulic hose, even the momentary surge pressure should be under the working pressure, otherwise, it will increase the probability of leakage and exposure, contaminate the machine or hurt the operator.
The burst pressure is the top pressure point when the hose is pressurized to the explosion. It comes from destructive tests in the lab.
In a real application, impulse loads convey hydraulic power to the actuator and fulfill specific actions, hydraulic hoses sustain repeated pressuring and pressure relief, and the type of hydraulic hose reinforcement used will determine how well that hose can handle regular impulse loadings.
Hydraulic hose reinforcement style
The reinforcement is the strength of all hydraulic hoses, it determines the working pressure of the hose. so it is vital to select the right one for your application, currently, there are three types of reinforcement styles in the market, and their functions differ mainly in pressure resistance and flexibility, of course, they can’t be separated from their individual construction.
- Braided: a braid of synthetic fiber (nylon and polyamide), steel wire (multi-strand high tensile steel wire), crafted by high-speed vertical or horizontal braiders.
- Spiral: multi-strand high tensile steel wire wound around the inner tube in parallel.
- Helical: Single thick steel wire wound around the hose helically with a certain gap.
Braided hydraulic hose
Braided hydraulic hoses find their application in two types in terms of materials used. They are textile-braided hydraulic hoses and steel wire-braided hydraulic hoses.
Braided construction has a crisscross wire arrangement. bunches of wires are wounded around the inner tube and overlapped each other. this construction contributes to its flexibility and allows the hydraulic hose has less bend radius.
It is not hard to understand the two different materials textile and steel wire, in comparison, the former has less strength than the latter, but it has more flexibility.
When the impulse is loaded in such hydraulic hoses, the braided hydraulic hoses expand and contract periodically, it leads to high-frequency friction between the overlapped braided wires, from the long run, it will fatigue the reinforcement and produce extra heat that will harm the hose, hence, this kind of hydraulic hose is not suitable high-pressure applications.
Spiral hydraulic hose
Spiral hydraulic hoses are reinforced with helical wire bunch, steel wires are wounded tightly around the hose at a specified angle for maximum dimensional stability. and they are parallel instead of crisscrossing, even plies spiral reinforcement is commonly used in hydraulic hoses, for instance, four or six plies of reinforcement, adjacent plies reinforcement is in opposing directions as to balance the force.
This construction results in high strength and less flexibility, spiral hydraulic hoses are designed to handle the high impulse application such as construction equipment, heavy-duty trucks, and fleet vehicle.
helical hydraulic hose
Helical hydraulic hose is special existence and it is exclusively designed for vacuum pressure use. The helical hydraulic hoses are commonly reinforced with braided steel wire or textile, and the helical single steel wire is spiraled at a certain distance and supports the hose against collapse when exposed to vacuum pressure.
They are commonly used in suction applications and return lines.
The hydraulic hose reinforcement forms the working pressure of hydraulic hoses, this gives us a guideline on how to choose the right hose, simply saying, for strength, the best choice would be a spiral wound hydraulic hose, if you prefer high flexibility, textile or steel wire braided hydraulic hoses are optimal. and if you choose a hydraulic hose for suction use, the helical hydraulic hoses are the right ones.
Sinopulse Group is a professional hydraulic hose manufacturer from China, We supply a complete series of hydraulic hoses that adhere to SAE and DIN EN standards, for the concrete requirement, please contact us any time, and we will reply to you with expert insight about your questions, don’t hesitate.