Ducting Insights

What is a Duct Hose?


At its core definition, a ducting hose is tube-like piece of equipment, with an opening at each end, which is made to transfer something from point A to point B. But this is a broad and over-simplistic term which does not properly explain the features and functionality of Rubber-Cal’s ducting hoses. These ducts are made specifically to move a range of materials. This range includes five categories – air of varying temperatures, dust and other fine particles, abrasives, larger non-abrasive materials, and fumes.

There is no one ducting hose product which will be perfectly suited to each different type of material movement. A wide variety of hoses are available, all with different designs and made with different materials, and all boasting different capabilities. Hose materials include PVC, coated polyester fabric, neoprene, silicone, thermoplastic rubber, aluminum, stainless steel and more. Each will provide different qualities. For instance, PVC ducting can provide a high degree of flexibility, while stainless steel is ultra strong and rigid. Some materials provide a higher working temperature, while others handle exposure to chemicals. To ascertain what kind of duct is needed in any particular setting, you need to know what will be travelling through it, what temperature it must be able to handle, whether it needs any resistance to chemical exposure, whether it will be used with positive or negative pressure, and what size is needed in terms of length and diameter.

In most cases, the open ends of the ducting hose are attached in place using a connector, clamp or belt. The applications for a hose can include everything from transferring air within an air conditioning system, sucking up sand, pebbles and other small debris and abrasives, to ventilating harmful fumes. In each of these applications – and many more – the hose itself does not have any powers of positive or negative pressure. It is simply there as a conduit, providing the channel to transfer a material from A to B.

Tips Before You Buy

How a Duct Hose is Measured


The size of a piece of ducting will normally have to be very precise. To make sure you get the exact size you need, you should know the basics when it comes to measuring a duct hose. As long as you know how to measure the length and diameters of a duct hose, you should be good to go.

One of the most important aspects to be aware of is how the length of a duct hose is measured. Because a lot of ducting comes in flexible forms and can stretch considerably, this can cause some serious confusion. When it comes to the length, the measurement will refer to the hose at its most extended point – the absolute maximum length it can represent. In other words tow people pulling in each end of the hose should get it to its maximum or selling length. A compression ratio could also be recorded. This tells people what size the hose can be reduced down to. For instance, a ducting product with a 5:1 ratio would be 5 ft at its maximum length, compressing down to 1 ft at its smallest point.

Another key figure in the measurement of ducting is the diameter. This is the size of the circular opening at the end of the duct hose. If a straight line was drawn across that circle at its greatest point and measured, that number would be the diameter. It should not be confused with the circumference, which you would get by measuring around the circular opening. There are two separate diameters often recorded, labelled ID and OD – inner diameter and outer diameter. The ID measures from the inside edge of the ducting wall. The OD will be slightly larger, as it measures from the outer edge, taking into account the thickness of the ducting wall.

Ducting insights

Silicone: An Excellent High Temperature Material


Silicone is an important part of the rubber family, mainly due to the incredible qualities it possesses. While most materials wilt under extreme heat, silicone is special because it can stand up to extreme temperatures without seeing damage. It is this quality that makes it stand out among other materials and even other rubber types.

While the limits of silicone’s heat resistance are unlikely to be tested in everyday life, it is vital in some areas. For example, industrial machinery relies on silicone ducting hoses as a key component. Heavy machinery, such as those used in plastic and metalwork, reach extremely high temperatures, and need materials that can stand the heat. Silicone ducting can handle temperatures reaching 550 degrees Fahrenheit without degrading. A specific silicone ducting product will feature a number after its name, which indicates the top temperature it can withstand.

It is important to distinguish the difference between heat resistance and being fire-proof though. Silicone is one of the best materials there is when it comes to low thermal conductivity, which allows it to bear serious heat without damage. However, it could still sustain damage if it comes into contact with an open flame. This is because silicone’s temperature resistance and burn points are different. A flame can cause it to ignite, but heat leaves it unaffected – to the point of the duct’s heat resistance.

Different silicone products feature different aspects, such as insulation or fiberglass supports to increase the strength of the ducting. But it is the silicone itself that is best used to contain heat, making it an excellent high-temperature material.