The main purpose of cold formed channels in structures is to serve as supporting members. Lip channels, open channels, Z-sections and top hats are the popular open channels in the construction industry. In the trailer manufacturing industry open channels such as top rails and side rails are commonly used. Open channels are easily customisable by customers to suit their specific needs and therefore one is not limited to certain industries or designs.
Cold formed open channels can be formed either by press braking a flat steel sheet or by roll forming into the desired shape. The first step in roll forming an open section is to determine the size of the slit strip, where after the coil needs to be slit into the correct width.
The slit strip will then be passed through different sets of rolls, known as passes. At each pass the profile is formed a certain number of degrees in a certain direction. When it is through the last pass the profile will be fully formed to the desired form and cut to the length required by the customer.
Lip and open channels are mainly used (and referred to) as purlins in steel structures. It is used as an alternative for hot/cold rolled channels. Other industries which use lip and open channels are shelving and racking, trailer manufacturers, construction, agricultural, etc.
In the construction industry lip channels as well as open channels are mainly used in buildings as a horizontal member which provide support to the roof decking or sheets.
In the construction industry top hats and Z-sections are very popular concepts. They can either serve as roof purlins or wall girts. Different sizes will be used, depending on the type of construction. The biggest advantage of top hats is that they are easy and fast to install.
The above mentioned are the common open channels in the market. The advantage of cold formed open channels is that it is not limited to any specs. Customers can design open channels to suit their needs.