Claw couplings - Page 3

How is the claw coupling constructed?

The claw coupling is constructed symmetrically. What does this mean? The two sections of the connection are the same — there is no distinction between socket and plug.

Obviously, the distinguishing features of the claw coupling are the claws (hooks) and the tabs into which these claws are inserted. In addition to this, the seal is also important — it is located inside.

As far as the manufacturing material is concerned, the claw couplings are most often made of galvanised cast iron, brass or stainless steel. As standard, they have a seal made of NBR oil-resistant rubber. Exceptions are stainless steel products, where the seal is made of viton.

The next important point is the installation method of the coupling. It depends on the end of the component in question, and there are several of these to choose from:

• for hoses,
• with female thread, 
• with male thread, 
• with cap.

In addition, there are also claw couplings in the form of tees.

What are the types of claw couplings?

You will find 3 of the most popular types of claw couplings on the market.

• Claw coupling 40 mm (GEKA claw coupling), 
• Claw coupling 41 mm,
• Claw coupling 42 mm.

We have prepared a description of each of them below.

Claw couplings 40 mm (GEKA claw couplings)

The coupling with a 40 mm claw spacing is also known as the GEKA claw coupling. They are very popular.

These types of products are most often used as water claw couplings. Therefore, you will find them in almost all industries, as well as in horticulture and construction.

They are made of brass as standard, but there are also stainless steel versions available. In the first case, they have a seal made of NBR rubber, while the second has a seal made of viton.

They are characterised by high strength, as they can withstand pressures of up to 16 bar, but this depends on the type of coupling. For some, this parameter is only 10 bar.

Claw couplings 41 mm

Couplings with a 41 mm claw spacing represent the US standard. They are used as air claw couplings wherever industry and construction uses US-origin equipment.

They are made of galvanised cast iron and their construction is distinguished by the presence of a special safety pin. Claw couplings have a seal made of oil-resistant rubber (usually NBR).

As far as working pressure is concerned, the American-style air claw coupling can withstand up to 10 bar.

Claw couplings 42 mm

Wherever there is no need for the US version, you will find couplings with a claw spacing of 42 mm. Also used for the transmission of compressed air, but is distinguished by the fact that it comes in several varieties.

These include:

• standard galvanised cast iron claw coupling with NBR seal (also available with hole for safety pin); 
• galvanised cast iron claw couplings with a brass seal on the rubber ring; 
• galvanised cast iron claw couplings with a ring to prevent disconnection and a NBR seal (has a higher pressure rating of 16 bar); 
• brass claw couplings with NBR seals; 
• stainless steel claw coupling with viton seal (here the permissible pressure is also 16 bar).

Excluding the two exceptions mentioned in the list, all other varieties can withstand a working pressure of 10 bar.

Claw couplings 42 mm are used for the transmission of compressed air in a wide range of applications. This means that they are used in installations, compressors and pneumatic tools, among others. A perfect example of their use is, for example, the claw coupling for sandblaster.

How to choose the right claw coupling?

To pick the right claw coupling, you need to pay attention to two important points. The first is the distance between the hooks (claws). While the second relates to where they will be installed.

For example, if you need a claw coupling for a hose, choose a product with an end for such installation. The same applies to threaded ends.

Finally, you should also pay attention to the size of the installation. Claw coupling ends are available in many cross-sections. Among the most popular are:

• 1/2 inch claw coupling,
• 3/4 inch claw coupling, 
• 1 inch claw coupling, 
• 2 inch claw coupling.

When you take the above into account, you will certainly select the right product for your needs.