how hydraulic hose is made

Hydraulic hoses are essential components of hydraulic systems, which are used in a variety of industries, including manufacturing, agriculture, construction, and transportation. Hydraulic hoses transmit fluids, oils, and gases under high pressure and extreme temperatures, and they operate in harsh and rugged environments. Knowing how a hydraulic hose is made can help you understand their design and quality, and make informed decisions when selecting a hydraulic hose for your application.

In this article, we will explore the manufacturing process of hydraulic hoses, from selecting the raw materials to testing the finished product. We will also discuss the different types of hydraulic hoses, their applications, and maintenance tips.

1. Raw materials

The first step in making a hydraulic hose is choosing the raw materials. Hydraulic hoses are typically made of synthetic rubber or thermoplastic materials, reinforced with high-tensile steel wire or fiber braids. The choice of materials depends on the application, operating conditions, and performance requirements.

Synthetic rubber is the most common material used in hydraulic hoses, due to its flexibility, durability, and resistance to abrasion, oil, and weather. Furthermore, synthetic rubber can withstand high pressures and temperatures, up to 10000 psi and 250°F, respectively. Some of the popular synthetic rubbers used in hydraulic hoses are Nitrile (NBR), Ethylene Propylene Diene Monomer (EPDM), Styrene Butadiene Rubber (SBR), and Fluoroelastomers (FKM).

On the other hand, thermoplastic materials are lightweight, non-conductive, and resistant to chemicals and UV light. Thermoplastic hoses are suitable for applications that require high flexibility, low weight, and frequent movement, such as mobile equipment and robotics. Some of the common thermoplastic materials used in hydraulic hoses are Polyethylene (PE), Polyurethane (PU), and Nylon (PA).

2. Hose construction

Once the raw materials are selected, the next step is constructing the hydraulic hose. The hose construction depends on the type and size of the hose, as well as the operating and environmental conditions. Typically, hydraulic hoses are composed of three layers: the inner tube, the reinforcement layer, and the outer cover.

The inner tube is the layer that comes into contact with the fluid being transmitted. It must be compatible with the fluid and resist chemical corrosion and thermal expansion. Synthetic rubber and thermoplastic materials are both suitable for inner tubes, depending on the application.

The reinforcement layer provides the strength and flexibility of the hose. It is typically made of high-tensile steel wire, braids, or spirals, which are embedded into the inner tube. The reinforcement layer determines the working pressure of the hose, and it can be single or multiple layers, depending on the pressure requirements.

The outer cover is the layer that protects the hose from environmental factors, such as abrasion, UV light, and weather. It can be made of synthetic rubber or thermoplastic materials, with different colors and textures, depending on the application.

3. Hose assembly

After the hose construction, the next step is assembling the different components into a complete hydraulic hose. Hose assembly involves cutting, crimping, and attaching the fittings and adapters onto the ends of the hose.

Cutting the hose involves using a special cutting machine or a sharp blade to achieve a clean and smooth cut. Crimping the fittings onto the hose involves compressing the metal sleeve or ferrule onto the hose and the fitting, using a hydraulic crimper or a hand tool. Crimping creates a permanent and leak-proof connection between the hose and the fittings, and it ensures proper alignment and retention.

Attaching the fittings onto the hose involves selecting the appropriate type, size, and orientation of the fitting, depending on the hose and the equipment. There are different types of fittings, such as JIC, BSP, ORFS, and SAE, each with its own sealing and thread standards. It is essential to use the correct fittings and adapters, and to follow the torque and installation instructions provided by the manufacturer.

4. Hose testing

The final step in making a hydraulic hose is testing its performance and quality. Hydraulic hoses must undergo rigorous testing, to ensure that they meet the industry standards and specifications, and perform safely and reliably under the expected conditions.

Testing a hydraulic hose involves subjecting it to high pressure and exposing it to extreme temperatures and environmental factors, such as oil, water, salt spray, and ozone. The hose must withstand a burst pressure that is at least four times the working pressure, without leaking or rupturing. The hose must also resist kinking, twisting, and bending, and maintain its flexibility and strength over time.

5. Types and applications

Hydraulic hoses come in different types and sizes, to suit a wide range of applications and functions. The most common types of hydraulic hoses are:

- High-pressure hoses, for applications that require pressures above 3000 psi, such as heavy machinery, mining, and drilling

- Low-pressure hoses, for applications that require pressures below 1000 psi, such as agricultural and industrial equipment

- Thermoplastic hoses, for applications that require high flexibility and mobility, such as robotics, aerial platforms, and marine equipment

- Specialty hoses, for applications that require customized or specialized features, such as chemical resistance, fire resistance, or electrical conductivity.

In conclusion, hydraulic hoses are crucial components of hydraulic systems, and their performance and quality depend on the manufacturing process and the selection of raw materials. Knowing how a hydraulic hose is made can help you appreciate its design and functionality, and make informed decisions when selecting a hydraulic hose for your application. Remember to choose the right type, size, and fittings, and to inspect and maintain your hydraulic hoses regularly, to ensure their longevity and reliability.