Strapping tool
Strapping tools are used for strapping , i.e. tensioning and closing straps and thus securing packages. Depending on the weight and nature of the load to be secured, steel straps or plastic strapping are used. The basic principle of how a strapping tool works is always the same: a tensioning roller pulls the strapping tight and a "locking unit" (sleeve, welding unit or notch lock ) hold the strap ends together.
Types of strapping tools
Strapping devices differ fundamentally according to the type of strapping on which the device is based, the type of drive and the type of closure.
Strapping devices initially differ in whether they were designed for steel packaging strapping , polyester textile strapping (ie thread structure strapping , woven strapping or composite strapping) or extruded plastic strapping strapping (PP strapping or PET strapping ).
There are manual strapping tools for all types of strap, in which the strap is tensioned by hand and then closed with a locking sleeve or, in the case of textile strapping, with a metal clamp. The straps can be tensioned and closed separately with tensioners and pliers or combined in one device - so-called combination strapping device.
It is also possible for all types of strapping to work with a pneumatic strapping device. In contrast to battery strapping tools, you are independent of the service life of a battery charge and can always repeat a certain tensioning force; This is of particular importance for export packers who have to meet certain safety requirements - especially when tensioning textile and lashing tapes. Battery strapping tools, on the other hand, have established themselves particularly in the processing of extruded plastic strapping, in which both the tensioning and the closing of the strapping are battery-operated "at the push of a button". The teeth of a tension roller grip the strapping and pull it taut. Afterwards, the straps are usually welded to one another by means of a friction lock, also known as a "friction-weld lock".
Combined strapping tools
Here the strapping is pneumatically tensioned around the package and as soon as the final tension is reached, the previously applied sealing sleeve is mechanically deformed twice or four times at the edges (the so-called "single or double notch). This is then done The strapping on top is automatically cut off The pneumatic pressure should be at least 4–5 bar flow pressure for this application.
Strapping devices for this use are designed with either a piston or membrane cylinder, which guides the scissor-shaped movement of the locking pliers in one device.
Sealing sleeves are available in a wide variety of forms, including: - Push-Type (closed sleeve shape) - C-shape (half-open sealing sleeve) - Magazine sleeves (here the sleeves are stacked in an open form to form a magazine)
Clamp and closer as separate units
In the steel industry in particular, separate clamps and closers are used instead of combination devices. These devices are usually available for widths from 19.00 to 31.75 mm. The packaging steel strip grades do not play a role in this application.
The strapping tape is stretched around the packaged goods around a so-called tensioner and the previously applied closure sleeve. The pneumatically applied tension is held while the so-called closer (single / double notch) is used and connects the closing sleeve firmly to the strapping.
After the closure has been formed, the tensioner is used by swiveling movements to cut off the strapping on top.