Kabel-und Metallwerke Gutehoffnungshutte Aktiengesellschaft

Marshall Richards Barcro Limited

Otto Uhlmann

Norbert Stephan

Klaus-Peter Uhlmann

Ottmar Leuchs

Walter Langhans

Hans-Jurgen Kloppner

Several lengths of tubing are interconnected either in advance by welding or brazing, or on-line by hollow plugs, and fed through an annealing furnace, a jacketing station, and a cutter, whereby flushing gas such as air, oxygen-enriched air, or an inert gas are sucked through the respective trailing end. The on-line, end-to-end connection can also be additionally used for tubings as prepared in advance and permits continuous processing, particularly combining process annealing with removal of oil residues.

Processing of copper tubing

Two water tanks, one behind the other, are disposed adjacent to the rolling gap for a piercing mill; the rolled seamless tube on a mandrel rod passes through both tanks during rolling. The tank closest to the gap contains also a mandrel holder, and following rolling the mandrel is retracted into that tank; this tank, but not the other one, is emptied and the mandrel on the rod is exchanged. The tank is refilled and the next billet can be rolled. Nozzles are provided to prevent water from escaping through openings in tank walls for the tube.

Mandrel exchange in piercing mills

Extruded, drawn and coiled copper tubing with wall thickness of 0.7 to 2 mm is soft annealed, straightened and jacketed in an extruder with a blend of polyvinyl chloride, chalk, a plasticizer and other additives for lubrication and stabilization. The jacket has inwardly extending ribs defining channels inbetween to enhance heat insulation.

Method of continuously making flexible, heat insulated metal tubing

The invention relates to an improved method and apparatus for tube drawing which relates to the use of a floating plug and die arrangement, the necessary draughting tension in the tube being drawn being generated by a rotatable tube block around which the tubing downstream of the die is wrapped. The invention proposes to mount a tube guide upstream of the die in such wise that the relative spacing between the guide and the die can be a minimum during threading-up of the die but increased during drawing.

Method and apparatus for drawing tubes

The invention is concerned with a method of and apparatus for the continuous drawing of metal tubing by the die and floating plug method using rotating drawing blocks to provide draughting tension. Tube lengths are processed joined end-to-end in sequential stages with accumulators provided between adjacent dies to permit the receipt of tubing from the upstream die and the supply of tubing to the downstream die to be at different rates. Each joint between lengths is broken upstream of a die but remade downstream thereof, the accumulator absorbing and supplying tube from/to adjacent blocks while the tube rejoining process is effected.

Tube drawing method and apparatus

A single capstan drum is used to pull alternatingly e.g. tubing through dies and coiling it on the periphery of the drum. The tubing to be drawn is taken from different stores, and while the tubing from one store is drawn, the other die and tubing of another store is prepared and inserted into that die, so that upon change-over the drum has to be halted merely briefly to fasten the end of the prepared tubing to the drum's periphery. The drawn tubing which was coiled dropped off the drum as soon as its end had left the respective die.

Drawing of elongated stock

A seamless pipe made by extrusion or piercing and having eccentric interior has the outside of one of its ends turned to concentric dimensions with its interior and is pulled through a peeling and scraping tool affixed to a positioning die, and over a mandrel which widens the pipe particularly in the zone of peeling.

Method of making seamless metal tubes

Copper tubing is drawn through a die by means of a rotating drum to which the front end of the tube is fastened and may remain fastened as the drawn tubing is coiled on the drum, or the front is released, so that frictional engagement of multiple coils on the drum provide for pulling. An annulus pushes the coils down, but is retracted or remains ineffective as long as the front end of the tube is fastened.

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Burgdorf, Germany

Otto Uhlmann