Suction hoses - Page 3

How is the suction hose constructed?

The suction hose has a reinforcement, i.e. a metal or plastic spiral. It ensures adequate rigidity.

In addition, this type of hose is usually characterized by its shorter length (usually between 1.6 and 2.4 m) and greater width. Among the most popular suction hoses, we distinguish:

• 75 mm/3 inch suction hose,
• 110 mm/4 inch suction hose,
• 150 mm/5 inch suction hose.

Suction hose differs from other hoses in terms of construction. As it circulates the liquid by means of the vacuum generated by the pump, it must not become distorted (flattened), as this would block the flow.

What are the different types of suction hoses?

The most popular types of suction hoses are:

• hard suction hoses,
• flexible suction hoses.

Hard suction hoses are primarily used to draw liquid from areas below the pump. They have additional reinforcement to protect against vacuum. Hard suction hoses are usually made of SBR rubber. They have a steel wire spiral and additional protection in the form of a textile braid. Hard suction hoses are also resistant to temperatures from -30 °C  to 70 °C.

Flexible suction hoses are made of plastic, which has much greater flexibility compared to rubber. Flexible suction hose is usually used to suck water from hydrants, a cistern, or a natural water reservoir.

However, this does not mean that a flexible suction hose is not suitable for pumping the medium. That is why many are also referred to as suction and discharge hoses.

What applications are suction hoses used for?

Suction hoses are primarily used as hoses between the fluid reservoir and the pump. This is why they are used on a mass scale by the fire brigade, for example. Using them, it takes in water from rivers, lakes or hydrants.

Suction hoses for fire brigades have also been developed specifically for firefighting competitions. They are usually characterised by a little more flexibility and special fire hose fittings so that competitors achieve better times when competing. In addition, the competition suction hose is very similar in design to the traditional one.

In addition, the septic tank hoses are very popular. It is essential equipment for any sewage tanker and is used to dispose of wastewater. In this case, very often, it appears as a suction hose with a strainer. This blocks debris that is too large from entering the hose.

There are also special-purpose suction and discharge hoses, for example for the food or agricultural industry.

What to pay attention to when choosing a suction hose?

When choosing a suction hose, pay attention to:

• Abrasion resistance,
• Type of medium,
• Environmental factors,
• Standards.
  

Abrasion resistance

No suction hose can avoid frictional damage during solid material handling. This is most noticeable in hoses with a rough inner tube.

Therefore, for such jobs, choose a hose that features high friction resistance.

Type of medium

Transporting materials for which the suction hose is not designed will sooner or later lead to hose failure. For example: a hose designed to transfer water will not effectively transfer petrol.

If this is the case, not only will the life of the hose decrease, but the medium may also become contaminated as a result of leaching from the hose walls.

Environmental factors

Environmental factors such as exposure to sunlight, extreme temperatures, or dragging on the ground affect hoses. At low temperatures, hoses tend to lose their flexibility. In hot temperatures, they can spoil.

Exposure to UV radiation from sunlight can cause chemical degradation of the material.

The local environment in which the hose is used also has significance. In chemical plants, hoses degrade faster than in agriculture, for example.

Standards

When buying hoses, pay attention to whether they meet European Union (EU) standards. This is particularly important when working with food products or chemicals.