Baling twine

Baling twine is the name of yarn, which is used for binding straw, hay or silage bales and keeps in shape. Other designations are binding twine or cord Erntegarn.

Baling twine is usually made ​​from polypropylene (PP ), as well as sisal is not (yet ) used. The yarn is tied around a straw to press the bales. In so-called highly compressed bales (small straw bales with a weight of about 10 to 20 kg), these are two cords, with large square bales 4-6 cords in round bales up to 20 cords; for round bales often comes a so-called round bale net instead of baling twine used.

In practice cords are omitted from the ball center partly for cost reasons. For the shelf life of the bales during transportation, especially the outer cords are important. Latest trends go to create a kind of bar code with different yarn colors. Thus, the bales can be easily assigned to one owner and unintentional charging by strangers is counteracted.

The required strength of the compacting twine is dependent on the type of straw press (eg whether square bales or round baler, etc.). The strength is defined by specifying the run length indirectly (unit: meters per kilogram ) determined, ie. the smaller the value of the run length ( per kg of baling twine ) is, the stronger the yarn. Typical data for the run length is about 130 m / kg, 150 m / kg, 320 m / kg. For highly compressed bales doing a "strength" ( run length ) of 200 m / kg for sisal and 400 m / kg in PP cord is sufficient. Small square bales with twine of "strength" ( run length ) 150 m / kg bound, for large square bales yarn with a "strength" ( run length ) of up to 110 m / kg is needed.

A special case are baler twine with a barrel length of 750 m / kg. This extremely thin yarns are used on the round baler instead of AC. By about 20 times the winding around the bale, a secure hold is here in spite of the small thickness of the yarn, is reached.

Commercially baling twine is on spools, each with 5 to 9 kg in 2- pack, usually offered. The coils are placed in the side of the baler and connected to the correspondingly labeled coil start of the machine. For this, the coils are wound so that they can be handled without the need to rotate the entire coil. The lead yarn is thereby withdrawn from the coil center, the coil itself remains stationary.

In the early days of Strohpressen partly iron wire was used to tie. Besides the high cost, it was mainly the high risk that animals would swallow iron parts, which put an end to this material.

Claims

Should be cut from the baling twine knotter easily. The yarn should be flexible enough to can be edited with the high speed of the knotter. The many turning points of a baler weigh the yarn on one side, but should not lead to a fraying. In addition, it must also satisfy the increased tensile stresses at grass silage bales. Even after a period of storage, the baler must be UV stable.

Tensile strength

Typical values ​​for the tensile strength of baler will be about 400 daN for a yarn of 110 m / kg, about 200 daN for a yarn of 150 m / kg and 140 daN for a yarn of 320 m / kg, wherein it is of course variations depending on material composition and manufacturers are.