Abstract: A friction stir welding tool for welding high-strength materials with one or more of the following features: 1) a curved transition geometry structure at the shoulder face and probe interface; 2) a tool material selected on the basis of an ultimate tensile strength determined at or above the temperature of the tool processing temperature; 3) a compressive stress at the point of crack fatigue introduced by mechanical or chemical means; and 4) a threaded probe with a) a major to minor thread diameter ratio that increases toward the distal end of the probe and/or b) with a curved thread root.

Abstract: A press mechanism and method for removing liquid from a traveling fibrous web such as in a paper making machine including first and second elongate extended press nips including an endless looped traveling belt passing over spaced guide rolls with first and second opposed press rolls pressed into the belt to form the extended nips between the press rolls and belt and opposed shoes within the belt pressing outwardly against the press rolls to form the extended nips with the shoes urged against the belt by opposed pistons having a liquid pressure chamber therebetween so that the reaction forces of the fluid on the pistons are cancelled with the web being carried through the nips on felts and following the belt between the nips.