This type of hose has a spiral steel wire ring inside, which serves to prevent the negative pressure from collapsing the pipe wall during suction. For negative pressure conditions such as pump inlet sections, sewage pumping, and river dredging, an absorbent hose should be used. If an ordinary water hose is used instead, the hos will be flattened, and the flow rate will drop sharply or even stop.
The water hose is only suitable for positive pressure clean water environments, such as water supply for equipment cooling, site watering, and vehicle washing. It does not have a negative pressure resistance structure and cannot transport oil products or chemicals. Its advantages are light weight, stable pressure resistance performance, and a relatively low price.
PVC hoses are cos-effective and come in various transparency options. They are widely used in scenarios such as low-pressure air, water, and dust suction. However, there are two significant drawbacks: Firstly, they become hard and brittle at low temperatures (close to 0°C), making them prone to cracking; Secondly, they are not resistant to oils and aromatic hydrocarbon solvents, and will swell and deform upon contact. If the working environment is relatively mild, PVC hoses remain a highly cost-effective choice.
When transporting gasoline, diesel, lubricating oil or hydraulic oil, special oil pipes with an inner layer of nitrile rubber (NBR) must be used. Ordinary rubber or PVC will swell when in contact with oil products, causing the inner layer to peel off or the pipe body to rupture. When purchasing, it is necessary to confirm whether there is an "OIL" or "Fuel" mark on the hose, and further filter based on whether the medium requires anti-static protection.
This hose has the ability to withstand both negative pressure and positive pressure, effectively combining the functions of "water suction hose" and "water hose". It is commonly used in scenarios such as tanker loading and unloading, mobile pumping stations, and sewage treatment where alternating suction and pumping are required. When choosing it, the main consideration is whether the working pressure and vacuum degree match.
The composite hose is composed of multiple layers of high-molecular films and inner and outer steel wires wound together. Its most notable feature is its lightness and softness, with the bending radius typically being only one-third of that of the rubber hose of the same diameter. In sites where hoses need to be frequently moved, such as chemical terminals, tanker loading and unloading, and offshore platforms, the composite hose can significantly reduce labor intensity. It is relatively expensive, but the overall usage cost is often lower.
