Hydraulic hoses are key components for transmitting power in hydraulic systems. There are many models, among which SN, SC, and SP are the three most common types. The main difference lies in the structure of the reinforcement layer and the applicable pressure range.

1. SN type hydraulic hose

 

SN type hydraulic hoses usually refer to hoses that meet the SAE standards R1AT, R1B, and R2, and their working pressure range is between 21 and 28 MPa. The structure of this hose usually consists of an inner rubber layer, a reinforcement layer, and an outer rubber layer. The inner rubber layer is mainly made of nitrile rubber (NBR), which has good oil resistance and wear resistance; the reinforcement layer is made of high-strength steel wire braiding or winding to ensure the high-pressure bearing capacity of the hose; the outer rubber layer usually uses chloroprene rubber (CR) or chlorosulfonated polyethylene (CSM) to provide good weather resistance and wear resistance.

 

Application scenarios: Commonly used in engineering machinery, agricultural machinery, excavators, forklifts and other equipment. Due to its good oil resistance and wear resistance, it is widely used to transport hydraulic oil, lubricating oil and other media.

 

Advantages:

  Simple structure, easy to install and maintain.

  Low cost, suitable for general working conditions.

  Good oil resistance and wear resistance.

 

Disadvantages:

  Limited high pressure bearing capacity, not suitable for high pressure systems.

  Fatigue damage may occur in high vibration environments.

 

2. SC hydraulic hose

 

SC hydraulic hose usually refers to hoses that meet SAE standards R9, R12, R13, and its working pressure range is between 35 and 70 MPa. The main difference between SC hose and SN type is that its reinforcement layer is wrapped with high-strength steel wire, which improves the pressure bearing capacity of the hose. In addition, the inner rubber layer of SC hose usually uses high temperature resistant hydrogenated nitrile rubber (HNBR) to cope with higher temperature working environments; the outer rubber layer uses oil resistant and better weather resistant synthetic rubber.

 

Application scenarios: Commonly used in large-scale engineering machinery, mining equipment, ships and other occasions with high pressure resistance requirements. In addition, it is also suitable for hydraulic systems in high temperature environments.

 

Advantages:

  Strong high pressure bearing capacity, suitable for high pressure systems.

  Good high temperature resistance, suitable for high temperature conditions.

  Long service life and high reliability.

 

Disadvantages:

  High cost, suitable for specific working conditions.

  Complex structure, high installation and maintenance requirements.

3. SP type hydraulic hose

 

SP type hydraulic hose usually refers to hoses that meet SAE standards R17, R19, R21, and its working pressure range is between 70 and 140MPa, which belongs to ultra-high pressure hydraulic hose. The reinforcement layer of the SP type hose is multi-layer ultra-high strength steel wire winding to ensure its extremely high pressure bearing capacity. The inner rubber layer usually uses fluorine rubber (FKM) with excellent high pressure resistance and oil resistance, and the outer rubber layer uses special synthetic rubber with impact resistance and wear resistance.

 

Application scenarios: Commonly used in hydraulic pumps, hydraulic cylinders, high-pressure testing equipment and other occasions with extremely high pressure bearing capacity requirements. In addition, it can also be used in hydraulic systems in extreme environments, such as deep-sea operations, aerospace, etc.

 

Advantages:

  Ultra-high pressure bearing capacity, suitable for extreme working conditions.

  Excellent oil resistance, high temperature resistance and corrosion resistance.

  High reliability and long service life.

 

Disadvantages:

  Very high cost, suitable for specific high-end applications.

  Extremely high technical requirements for installation and maintenance.

 

Summary

The main differences between SN, SC, and SP hydraulic hoses are their working pressure range, reinforcement layer structure, inner rubber layer material, and outer rubber layer material. SN type is suitable for medium and low pressure systems, SC type is suitable for high pressure systems, and SP type is suitable for ultra-high pressure systems. When selecting hydraulic hoses, it is necessary to make reasonable choices based on the specific working environment, pressure requirements and medium characteristics to ensure the safety and reliability of the system.