What are the structural characteristics of large-diameter high-pressure hoses?

　　 Large-diameter high-pressure hose It is a type of hose, primarily distinguished by its large diameter and high-pressure rating. Large‑diameter high‑pressure hoses are suitable for conveying hydraulic fluids such as alcohol, hydraulic oil, fuel oil, lubricating oil, water, emulsions, and hydrocarbons, enabling high‑pressure fluid transport or hydraulic power transmission.

　　Large‑diameter high‑pressure hoses consist of an inner rubber layer, a middle rubber layer, steel‑wire braided layers I, II, and III, and an outer rubber layer. Since these hoses do not include a reinforcing carcass, they can be extruded directly using an extruder; for hose fabrication, a forming machine is used to wind tape around the inner rubber layer; and when manufacturing water‑suction hoses, a metal helical wrap is required.

　　As the application scope of large‑diameter, high‑pressure hoses continues to expand, their product portfolio has also begun to grow. Initially used primarily in the petroleum and coal industries, these hoses are now finding applications in an increasing number of sectors. In today’s petroleum industry, in addition to drilling and vibration‑resistant hoses, other types are being adopted as well. Due to national policy considerations, some domestic manufacturers have already started producing such hoses; however, floating or semi‑floating oil‑transport hoses and deep‑sea subsea oil‑transport hoses still rely on imports. Meanwhile, the coal industry is expanding the range of hose types it employs, including telescopic hoses for coal‑bed water monitoring and sealing devices. These products are utilized for water injection and grouting operations prior to fully mechanized mining in underground coal mines.

　　According to available data, China’s current hose production capacity stands at 500 million to 700 million standard meters, while the nation’s actual output in 2005 fell short of 400 million standard meters, indicating substantial untapped production potential. In hose manufacturing, automotive hoses, wire‑braided hoses, and fabric‑reinforced hoses account for a significant share. Among these, automotive hoses are one of the fastest‑growing segments, closely tied to the rapid expansion of China’s automotive industry. Large-diameter high-pressure hose It is also a variety that has experienced rapid development in recent years. Its growth has been closely tied to technological advances in China’s petroleum and coal industries, as well as the expanding use of construction and agricultural machinery.

　　Everyone is familiar with the application knowledge of large‑diameter, high‑pressure rubber hoses. Currently, these products are primarily used in hydraulic supports for mining and in oilfield development, and they are suitable for construction projects, lifting and transportation, metallurgical forging, mining equipment, marine vessels, injection molding machinery, agricultural machinery, various machine tools, and mechanized operations across diverse industrial sectors—handling water‑based fluids and other liquids. Their maximum working pressure can reach 70 to 120 MPa.

　　To achieve better application results, what issues should be kept in mind during use?

　　1. The bending radius shall not be less than the specified value to prevent damage to the hose reinforcement or premature failure due to excessive stretching.

　　2. Based on the operating conditions, select the correct hose model and specifications; never use the wrong type or substitute it with an inappropriate one.

　　3. When using the =, adjust the pressure slowly and evenly to prevent damage caused by a sudden pressure surge.

　　4. When relocating the workpiece, it should be lifted off the ground and not dragged to avoid scratching the outer rubber coating.