Overload protection function of hydraulic tensioner

In mechanical equipment, hydraulic tensioner is not only used to adjust the tension of belt or chain, but also bears the important overload protection function.

Principle of overload protection

The overload protection function of hydraulic tensioner is based on the basic characteristics of hydraulic system, that is, the fluidity and compressibility of hydraulic oil under pressure. When the system load increases suddenly, the tension of belt or chain will increase rapidly. At this time, the hydraulic oil inside the hydraulic tensioner will release part of the pressure through the pressure relief valve or specific pressure relief channel, so as to avoid the tension exceeding the design limit.

Specifically, there is a pressure threshold inside the hydraulic tensioner. When the tension caused by the system load exceeds this threshold, the hydraulic oil will be automatically released through the pressure relief mechanism to reduce the pressure in the hydraulic cavity. This pressure relief process is instantaneous and can effectively prevent excessive tension from damaging belts, chains or other transmission components.

How to implement overload protection

The overload protection function of the hydraulic tensioner is mainly achieved in the following two ways:
1. Pressure relief valve design: The hydraulic tensioner is usually equipped with a pressure relief valve. When the pressure in the hydraulic chamber exceeds the set value, the pressure relief valve will automatically open and release part of the hydraulic oil to reduce the pressure. This design is simple and reliable and is widely used in various types of hydraulic tensioners.
2. Hydraulic oil flow control: In some high-end hydraulic tensioners, the overload protection function is achieved by precisely controlling the flow of hydraulic oil. When the system load increases, the flow path of the hydraulic oil changes, and part of the hydraulic oil is directed to the low-pressure area to avoid excessive pressure.

Whether it is a pressure relief valve or hydraulic oil flow control, its core goal is to ensure that the tension is always within a safe range by reducing the pressure in the hydraulic chamber.

The importance of overload protection

The overload protection function is of great significance in hydraulic tensioners, mainly reflected in the following aspects:
Preventing component damage: When the system load increases suddenly, excessive tension may cause belt breakage, chain tooth skipping or bearing damage. The overload protection function of the hydraulic tensioner can effectively avoid these problems and extend the service life of the equipment.
Improve system reliability: The overload protection function ensures the stability of the transmission system under extreme working conditions, reduces the failure downtime caused by excessive tension, and improves the operating efficiency of the equipment.
Reduce maintenance costs: By avoiding component damage caused by overload, the hydraulic tensioner reduces the maintenance requirements of the equipment, reduces maintenance costs and time costs.
Enhance safety: The overload protection function not only protects the equipment, but also avoids safety accidents that may be caused by component damage, providing higher safety protection for operators.