A method for welding a welded part to a component is carried out as arc ignition welding by use of direct current, having a bias current phase in which an arc is formed between the negatively polarized welded part and the component, and a subsequent main current phase for melting material to the joint. The welded part: a) is a galvanized sphere made of C10C having a roundness G500, wherein the size of any zinc inclusions under the surface of the sphere equals 10 micrometers at maximum, orb) is formed by welding a galvanized sphere made of C10C having a roundness G500, wherein the size of any zinc inclusions under the surface of the sphere equals 10 micrometers at maximum, to a connection element.

A projection portion is formed on a distal end surface of a supply rod with which a surface of a flange is brought into close contact. A circular-arc receiving surface is formed at a boundary portion between the distal end surface and the projection portion, and is configured to fit a flange outer peripheral portion. One side of the circular-arc receiving surface is continuous with the distal end surface, and another side of the circular-arc receiving surface is continuous with an inclined guide surface. The close contact of the flange with the distal end surface is achieved with a magnet of an advancing/retreating type provided in the supply rod.

An anchoring assembly for anchoring a liner of a cured lining material arranged to be applied in liquid form to a metal object provided with the anchoring assembly, the anchoring assembly including an elongated mounting pin and a ferrule provided at a first end thereof, wherein the pin is arranged to be mounted at the first end to the metal object, the anchoring assembly further including a plurality of spaced anchor fins connected to the pin at a second end and extending radially outward relative to the pin, wherein the ferrule includes a radially outwardly extending place holder part arranged to be held by a ferrule holder during mounting of the pin at the first end to the metal object.

A control unit and method for a joining system having at least one joining station, which is designed to join at least one first joining element to a workpiece, determines actual data with respect to a first joining element joined to a current workpiece by the joining station. The control unit and method determine, in accordance with the actual data, a subsequent control instruction for the joining station for joining a first joining element to a subsequent workpiece.

A system is provided comprising a hardened stud body and an unhardened stud subunit coupled to the hardened stud body. The hardened stud body may comprise a first composition having by weight between 17% and 21% chromium, between 2.8% and 3.3% molybdenum, between 50% to 55% nickel, and between 4.75% and 5.5% niobium. The unhardened stud subunit may comprise a second composition having by weight between 20% and 23% chromium, between 8% and 10% molybdenum, at least 58% nickel, and between 3.15% and 4.15% niobium.

A welding tool for a robot welds together a first component and a second component by using a metallic welding element disposed within a through-hole in the second component. The welding tool includes a welding torch attached to an arm, an element pusher that is attached to a distal end of the arm and disposes the held welding element between the welding torch and the through-hole and disposes at least a part of the welding element within the through-hole, a component pusher attached to the distal end of the arm and movable in an axial direction of a distal end of the welding torch, and a driving device that presses the component pusher against the second component. The element pusher is movable in the axial direction relative to the component pusher.

A welding device for welding a stud to a substrate along a welding axis in a welding direction, comprising an inert gas cover with an inert gas inlet arranged as a ring around the axis, with an inert gas outlet, and an opening facing the welding direction, the opening having transversely to the welding direction an opening diameter, wherein the inert gas inlet is at an inlet distance from the opening counter to the welding direction, wherein the inert gas outlet is at an outlet distance from the opening counter to the welding direction, and a holding device holding the stud within the cover during welding, the holding device having an outside diameter and a stud receptacle with an inside diameter, wherein the outlet distance is at least half of a difference between the opening diameter and the outside diameter or at least the same size as the inlet distance.

A method of welding a weld stud to a workpiece and of checking the strength of the welded joint includes the steps of providing a tool, a workpiece, and a weld stud, the weld stud including a shank and a polygonal shaped head; welding the weld stud onto the workpiece; applying the tool to the polygonal shaped head section of the stud; applying a predetermined test torque to the weld stud with the tool; and checking the welded joint for satisfactory acceptance of the test torque.

A method for joining joining elements to components, in particular for stud welding, comprises the steps of: providing a joining element having a first joining surface, and providing a component having a second joining surface; preparing the first or the second joining surface, wherein the preparation step includes detecting the state of the first or the second joining surface; joining the joining element to the component. The preparation step uses least one of the following detection methods: (i) an electrical contact resistance measurement, (ii) an electrical conductivity measurement, (iii) a fluorescence measurement, and (iv) a laser measurement.

A device for holding a stud with a radially flange and an axial shank. The holding device comprising a collet including a clamping section and a hollow insertion section defining an insertion axis such that the stud can be inserted via the insertion section to the clamping section. The holding device further comprising a tubular securing sleeve located radially inward of and concentric with the insertion section. A clearance is defined between a bottom end of the securing sleeve and a top end of the clamping section and is adapted to releasably receive the stud flange. A first air flow channel in a first direction is adapted to blow feed the stud into the collet; and a second airflow channel oriented in a second different direction is adapted to maintain the stud shank substantially in line with the insertion axis.