The importance of steel wire reinforced rubber hose

Rubber hose is a hose made from rubber ingredients. Widely used in industry, agriculture, military industry, medical treatment and people’s livelihood. Rubber hoses are divided into pure rubber hoses (non-reinforced hoses) and reinforced hoses. Reinforced rubber hose refers to a hose with one or more layers of reinforcing material between the inner rubber layer and the outer rubber layer or only outside the inner rubber layer (no outer rubber layer). There are various reinforce layer structures, and there are basically two categories of reinforce materials: fiber and metal (metal reinforce materials are generally steel wires).

Hose pressure rating

The working pressure of reinforced rubber hoses is roughly divided into 5 levels according to the SAEJ 517 standard: low pressure, medium pressure, high pressure, very high pressure, and ultra-high pressure. Within the same grade, the pressure depends on the inner diameter of the hose. Under the same structure, the smaller the inner diameter, the higher the pressure it can withstand. The larger the inner diameter, the lower the pressure it can withstand. The low-pressure hose is reinforced with fiber material. Medium-pressure hoses can be reinforced with fiber materials or steel wires. High-pressure, very high-pressure and ultra-high-pressure hoses are generally reinforced with steel wire.

Only special-purpose hoses are reinforced with aramid fiber materials whose volume and mass are smaller than steel wires and whose tensile strength is higher than steel wires. The reinforce layer of steel wire reinforced rubber hose has a braided structure and a winding structure, and sometimes a hybrid structure of the two is also used. Under the same conditions, the wound structure hose has higher pulse pressure resistance than the braided structure hose. This is because there are no interweaving points between the wrapped steel wires like in a braided structure. Therefore, there will be no local friction between the steel wires.

Steel wire braided construction

The braided structure is composed of two strands of steel wires running in the forward and reverse directions intertwined in the form of “two up and two down”, forming a mat structure. According to the hose pressure requirements, it can be single layer or double layer. In addition, steel wire specifications also vary in thickness.

Steel wire winding structure

The winding structure is composed of two adjacent layers of steel wires wound in reverse spirals, and the steel wires are not intertwined with each other. The steel wire winding layer is an even number layer. According to the pressure requirements of the hose, there are generally 2 layers, 4 layers and 6 layers. Steel wire also comes in different thicknesses.

Special large diameter rubber hose

Steel wire braided and wound rubber hoses, the inner diameter is generally less than 51 mm. Hoses with an inner diameter greater than 51mm are called large-diameter hoses. Such as oil drilling rubber hose, offshore oil transportation rubber hose, dock exhaust and suction rubber hose, dredging rubber hose, ore and other solid material transportation rubber hose. Agricultural irrigation and drainage rubber hoses and other drainage and suction hoses are also large-diameter rubber hoses. But its reinforce layer is mainly impregnated textile fabric (called interlayer).

It is supplemented by armored steel wire spirals to maintain the circular shape of the hose and withstand positive and negative pressures. Offshore oil transmission rubber hose is an offshore single-point moored crude oil transportation hose with an inner diameter of 150 to 600 mm. It is divided into two types: underwater and floating. Due to the harsh usage conditions of this hose, its structure is relatively complex. In addition to the fabric buffer layer, the reinforce layer is mainly composed of multi-layer steel cord winding layers and steel wire spirals. The cord-wrapped steel wire can be a single steel wire or a thin ply wire rope.

Oil drilling rubber hose, with an inner diameter of 64 to 102 mm and a working pressure of 27 to 52MPa, is a large-diameter ultra-high-pressure rubber hose. This kind of hose is reinforced with a single thick steel wire or a thin twisted steel wire rope, usually 4 layers. The wharf exhaust and suction rubber hose has an inner diameter of 102~304 mm and a working pressure of 1.55MPa. Used to discharge and absorb oil and petroleum products between terminals and tankers.

It is actually a soft connection between the terminal and the oil pipeline of the tanker to adapt to the up and down and horizontal floating of the tanker in the water. This kind of hose is generally reinforced with steel cord winding, supplemented by thick steel wire spirals. The cord layer is generally 4 layers. This kind of exhaust and suction rubber hose can also be used to exhaust and absorb other chemicals.

The role of steel wire in rubber hoses

Reinforced rubber hose is a flexible conduit. It is used to transport liquids, gases and granular or powdery solid materials, and transmit hydraulic and pneumatic power. In the medium transfer, hoses must withstand internal or external pressures (positive or negative pressure) of varying sizes. Therefore, the main function of the steel wire reinforce layer is to strengthen the rubber hose. It has the ability to withstand positive and negative pressure. During use, the pressure experienced by rubber hoses, especially hydraulic hoses, is not constant. It has to withstand periodic pulse pressure from 0 pressure to 125% working pressure. Sometimes it has to withstand higher instantaneous impact pressure. In the design of rubber hoses, a safety factor needs to be added to the required working pressure. That is the ratio of the smallest burst pressure to the largest working pressure. The safety factor ranges from 2 to 5, generally.

Rubber hoses, especially hydraulic hoses, must withstand periodic changes in inner diameter increase and decrease and length elongation and shortening due to pressure during operation. It also has to withstand cyclic flexural changes caused by bending. In addition, there are also deterioration effects on the inner and outer rubber layers caused by the medium, climate, high and low temps, etc. All these factors not only directly affect the performance of the rubber hose, but also affect the service life.

In the design of rubber hoses, the main factors for steel wire are tensile strength and toughness. Select the proper steel wire according to the pressure rating of the hose. In general, the lower the tensile strength of the steel wire, the better the flexibility. At the same time, the higher the tensile strength, especially at its upper limit. The worse the flexibility, the greater the brittleness. However, it is more important to develop steel wires with high strength and good flexibility. This will play an important role in improving the performance and service life of rubber hoses.

The bonding between steel wire and rubber is very important for the flex resistance and pulse performance of rubber hoses, especially hydraulic hoses. After the rubber hose is formed and vulcanized, the components of the pipe body are well bonded. Make the tube body an indivisible whole. This is one of the issues that must be considered in hose design.

How many kinds of rubber hose has steel wire reinforce?

In fact, many kinds of rubber hoses have steel wire between the inner and outer layer. In a word, all the rubber hoses that require high pressure resistance have a steel wire reinforce layer. Next, let me introduce you some typical ones.

First, rubber water suction hose

Suction rubber hose is a flexible industrial hose which adopts natural rubber or SBR. It has great wear, weather and ozone resistance. Thus it can work at outdoors for a long time in any weather conditions. Rubber water hose widely serves in construction, water supply, waste water discharge and municipal project. Besides, it is also used in emergency. In rainy season, flood will happen frequently. In this case, you can use the suction rubber hose to discharge the flood. While with a large diameter rubber hose, the discharge work can be more effective.

In agriculture, people often use PVC hoses like PVC layflat hose to deliver water. But if you need to drag the hose, it will wear the PVC flat hose. Then it will cause water leakage. On such occasion, you can use the suction rubber hose to deliver water. Because there will never be problems like leakage and kink.

Second, hydraulic hose

Hydraulic hose is the most typical steel wire hose among all the flexible hoses. Because of the special function, the pressure inside the hydraulic hose pipe is very high. In general, it can be several Mpa. But sometimes it can reach dozens of Mpa. Thus general rubber structure and fibre reinforce can not meet the pressure requirement. Then there must be steel wire as the reinforce layer. What’s more, the steel wire can be 2 layers, 4 layers and 6 layers based on different pressure.

Third, pressure washer hose

As the name shows, power washer hose works at a high pressure. It is to spray high pressure water to wash cars and remove the dirt from surfaces. The max pressure inside the hose can reach 4000 psi. Thus the reinforce layer should be steel wire. In general, there are 2 layers of steel wire in a pressure washer pipe. It can deal with most of the usages. But in some special cases there can be more reinforce layers.

Fourth, composite hose

Composite hose contains a series of hoses for various apps. For such hose, each type has its specific use. In oil field and drilling project, you need a composite oil hose to deliver crude oil. But in sea drilling platform, you need a heavy duty composite oil hose. We know that there is salty moist above the sea. Thus the salty moist will corrode the oil hose. Therefore, the composite hose should be resistant to acid, alkali and corrosion. Besides the drilling platform, it is also ideal for the oil transfer between ships and docks. Besides above hoses, there is a marine composite hose. It mainly serves in various ships like oil tanker and container vessel. While in chemical industry, you may need a composite chemical hose to deliver various chemical products.

In the gas station, there is a new composite hose that gradually replace the steel pipe. That is the petrol station HDPE hose. It adopts high density PE as the raw material with reinforce layer and resistant layer. The traditional pipe to deliver oil in a gas station is steel pipe. But it is buried underground. Thus after a long time, it will be corroded. Then it will cause leakage, which not only pollute the soil, but also cause huge loss. While the HDPE pipe has a special structure which has excellent corrosion resistance. Besides, it has a two-layer structure which provides double protection. Thus you never have to worry about the leakage problem. What’s more, it has a extremely long service life which can be over 50 years.

Last, sweeper hose

Sweeper hose is the specific hose in a street sweeper. It is made from natural rubber or other synthetic rubbers which has great wear and corrosion resistance. Besides, there is a steel wire layer inside the rubber to make the hose have a strong structure. Sweeper hose is to suck the dirt in the street. While there are leaves, branches, stones and many other abrasive materials which can wear the hose. But such rubber material handling hose has excellent abrasion resistant. Thus it can deal with these abrasives well without any problem.

Above are some typical rubber hoses which have steel wire layer inside. In fact, there are many other hoses have steel wire hoses as reinforce. Such as food suction hose, peristaltic hose, concrete pump hose, etc. While besides rubber hose, many plastic hoses have steel wire reinforce layer. These hoses include PVC steel wire duct hose, PU ducting hose, etc. In a word, any apps that requires high pressure and vacuum resistance should choose a hose with steel wire reinforce.

Orientflex is a hose manufacturer which has 15 years’ experience. Besides the hoses mentioned above, we can offer you many other hoses like auto rubber hose and silicone hose. Besides the standard hoses, we can offer you custom hoses. Then it can fit your work well. Because of high quality and unique one-stop service, Orientflex has been one of the most popular hose supplier. While Orientflex hose is more and more famous in the world.