JACTON offers super long stroke screw jacks, like 2m, 3m, 4m, 5m, 6m...until 9m. But not all screw jacks can be produced with long stroke. Usually the maximum travel of a single worm screw jacks lift is 3m to 4m. If this length is exceeded, the lifting screw is easily to get deformed and bent during use, especially when the jack is used to raise the object. Larger screw jacks have their maximum stroke available limited only by the available length of steel bar stock and the practical ability to handle, machine and transport the lead screw and the complete screw jacks. Practical lengths will also be affected by whether the screw is to be subjected to compression or tension loads. Depending on diameter the length can be limited due to deformation of material in the machining process or column strength of the screw when subjected to compression loads.