Rubber hoses are flexible conduits composed of an inner rubber layer, a reinforcing layer (such as fiber braid or steel wire braid), and an outer rubber layer. They are widely used for transporting various gases, liquids, and slurries, and are often referred to as the "flexible arteries" of industry.

The performance of rubber hoses is highly dependent on the choice of inner rubber layer to withstand different transported media:

• General-purpose hoses: Such as water and air hoses, often use blends of natural rubber (NR), styrene-butadiene rubber (SBR), or butadiene rubber (BR), which are low-cost and highly flexible.

• Oil-resistant hoses: Crucial in automotive fuel and hydraulic systems, these must use nitrile rubber (NBR) because its molecular chain contains polar nitrile groups, providing excellent resistance to oils.

• High-temperature/chemical-resistant hoses: When transporting steam, hot water, or corrosive chemicals, ethylene propylene diene monomer (EPDM) rubber (water-resistant, steam-resistant, and aging-resistant) or fluororubber (FKM) rubber (high-temperature resistant and resistant to strong corrosive media) is required. • Reinforcing layer: Braided, wound, or knitted using high-strength rayon, polyester, nylon, or steel wire to withstand internal pressure.

Currently, hoses are developing towards higher performance, greater versatility, and longer lifespan. Examples include high-temperature cooling water hoses in automotive engine compartments and high-temperature, oil-resistant hoses for turbochargers. In the petroleum industry, subsea hoses used in deep-sea oil and gas extraction, which must withstand enormous pressure and harsh environments, represent one of the pinnacles of hose technology.