Lightweight gates of high-strength steel for improved worker safety and cattle handling This report presents the work with developing a lightweight gate of high-strength steel for the handling of cattle. The project was conducted as a European Innovation Partnership (EIP) project. The project group consisted of co-workers from the unit of Agriculture and Horticulture and the unit of Process and Environmental Engineering at Research Institutes of Sweden (RISE Jordbruk och trädgård och RISE Kretsloppsteknik), Parsteel AB (former Nilssons Plåtindustri AB), SSAB EMEA AB, Sophie Atkinson at Smart Animal Handling, Swedish University of Agricultural Sciences (SLU) in Skara and the cattle farmer Lars Olsson. The main objectives of the project were to develop a lightweight gate weighing at least 50% less and being three times as strong as a traditional gate for cattle handling. The main motive was to improve the ergonomic conditions and working environment for the animal handlers. Additionally, for the safety of both animals and handlers, the gate must withstand the loads from cattle. Other objectives were to design and construct a gate that does not exceed the price of a high-quality gate and not contribute to increased negative environmental impact. A lightweight gate can be made of various materials such as plastic, fiberglass or steel. Regarding the project group's participants and their competencies, in addition to the numerous requirements placed on a lightweight gate, the choice fell on high-strength steel. High-strength steel is characterized by having high yield strengths, up to 1300 MPa, in comparison with traditional construction steel with yield strength of 355 MPa. For the specific lightweight gate, steel pipes with a yield strength of approximately 750 MPa were chosen. These pipes are mainly used in the automotive and engine industry, where high demands are placed on strength while at the same time a light construction is desired. The gate itself was designed during the project and several details were examined and developed in regard to functionality and safety for both cattle and handlers. The work environment legislation states that gates must be dimensioned and anchored so that the animals cannot break out (AFS 2008:17). The gates must also not pose a risk of injury to the cattle. In order to work safely with cattle, knowledge of cattle behavior is essential and consequently the report contains a chapter describing cattle senses and behavior. Both the lightweight gates and the handling system, built up by the gates, must be adapted to the cattle. In the project, the bud box handling system was tested. The handling system was originally developed to make use of the behavioral characteristics of cattle to encourage forward movement in the desired direction. In the project the handling system's functionality and safety, by using lightweight gates and additional equipment and components, were further designed. The handling system was tested in two groups of heifers at the SLU Götala Beef and Lamb Research Centre. The lightweight gates were also tested in a dairy herd and a beef herd, while hoof trimming, and at a small-scale abattoir. Generally, the light weight of the gates was considered an advantage as the handling of the gates is simplified also resulting in more frequent use of the gates, increasing safety for both animals and humans. During the project, several strength tests were performed by building unique test rigs. In one test rig, the weld of the pipes of the lightweight gate was tested. In another test rig, the strength of lightweight gates, compared with traditional gates on the market, were tested. The outcome of the tests confirmed the original aim of the project, a lightweight gate made of high-strength steel, about 50% lighter and at least three times as strong as traditional gates, had been developed and designed during the project period.