9 Differences Between Hard Tube & Soft Tube of Hydraulic Tube

Hard tube and soft tube of hydraulic tubes are commonly used pipe forms in hydraulic system, and they have their own advantages in structure, characteristics and application. Choosing the right hydraulic tube requires comprehensive consideration of the system's working conditions, installation environment and maintenance requirements. The following details the differences between the two in various aspects and other key factors.

Structure

Hard hydraulic tubes are usually made of metal materials (such as steel, copper, aluminum, etc.), with strong rigidity and pressure resistance. Among them, seamless steel pipe is the common material for hard hydraulic tubes, and the inner wall is usually smooth, which can reduce the pressure drop in the hydraulic system.

Soft hydraulic tubes are usually composed of an inner layer pipe, a reinforcement layer (such as steel wire braid, steel wire spiral, etc.) and an outer protective layer, which have certain softness and bending properties. In some applications, soft hydraulic tubes can also be used in conjunction with casing pipe to provide additional external protection for the system.

Bending performance

Hard hydraulic tubes are relatively rigid and difficult to bend. Their bending radius is relatively large. When installing, the routing and layout space need to be considered. They are suitable for straight or large bending radius pipeline design.

Soft hydraulic tubes are more flexible and can be bent and adapted to different installation environments more easily. Therefore, they are more suitable for occasions where frequent bending is required, but excessive bending may also accelerate aging.

Pressure resistance

Hard hydraulic tubes usually have high pressure resistance and can withstand large working pressures. They are suitable for high-pressure environments. At the same time, metal materials have good adaptability to temperature and medium chemical properties. The excellent pressure resistance of hard tubes also makes them outstanding in some extreme environments, such as oil drilling equipment used in conjunction with drill pipe.

The pressure resistance of soft hydraulic tubes is relatively low, which is usually limited by the structure of its inner layer and reinforcement layer. Generally, it is necessary to select the appropriate hose type and specifications according to the working conditions.

Temperature adaptability

Hard hydraulic tubes can generally withstand a wider temperature range and are suitable for high or low temperature environments.

The performance of soft hydraulic tubes may decrease at extreme temperatures, so it is necessary to refer to the product description when selecting.

Safety and failure modes

Hard hydraulic tubes are prone to cracks or breaks under overpressure or improper installation, and the risk of failure is relatively high.

Soft hydraulic tubes usually show gradual leakage when they fail, and there are usually obvious signs of aging or wear in the early stage, which is convenient for early prevention and replacement.

Fluid dynamics

The inner wall of hard hydraulic tubes is usually smoother, which is conducive to reducing fluid resistance and pressure loss.

Soft hydraulic tubes can also maintain good fluid transmission under reasonable design, but after long-term bending, they may produce additional resistance due to wear of the inner wall.

Vibration and shock absorption capacity

Hard hydraulic tubes may require additional support or vibration reduction measures in high vibration environments to prevent breakage.

Soft hydraulic tubes can effectively absorb vibration and shock due to their good flexibility and reduce system fatigue.

Installation and replacement

Hard hydraulic tubes are relatively complicated to install and replace, requiring welding, threaded connection or special joints. The construction process requirements are high, and professional personnel are required for maintenance.

Soft hydraulic tubes use simple installation methods such as end crimping, threaded connection or clamp clamping, which is easy to replace and adjust. In addition, hydraulic hoses are often connected by pup joints in some applications to further simplify the pipeline layout.

Cost and maintenance

Hard hydraulic tubes have higher initial investment due to their expensive materials and installation process, but they have a longer life and lower failure rate in a stable operating system; however, once damaged, they are difficult to repair.

Soft hydraulic tubes have relatively low material costs and installation costs, and are easy to repair and replace, but they may age prematurely due to fatigue in the case of long-term or high-frequency bending, and need to be inspected and replaced regularly.

Summary

Hard hydraulic tubes or hoses need to be selected according to the specific hydraulic system requirements and working environment. When selecting, factors such as the characteristics of the conveying medium, working pressure, temperature range, safety requirements, and budget should be considered. If you are not sure, it is best to consult a professional hydraulic engineer or supplier for accurate advice.