DE3119539A1 - Process for the treatment of copper pipes - Google Patents

Abstract

In a process for the treatment of copper pipes which are brought to the final dimensions by drawing with the use of drawing oil and are finally soft-annealed, an oxidising atmosphere being maintained in the interior of the pipe, the oxidising gas is passed in continuously in an exactly metered amount by regulating the pressure or the flow rate.

Description

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Cable and metal works Gutehoffnungshütte Aktiengesellschaft

2-254 14 '. 05.81

Process /. For treating copper pipes

The invention relates to a method of treating before. Copper pipes made by pressing or rolling and subsequent Drawing can be brought to the finished size using drawing oil and after the last drawing process be heated to evaporate the drawing oil and anneal the tube, with the drawing oil vapors from inside be driven out by the introduction of a gas, in which individual pipe lengths are connected at the end in a gas-permeable manner a section of the pipe length to more than? 600 C, preferably by means of resistance or induction heating heated in continuous flow, and in the. An oxidizing gas is introduced inside the length of the pipe will.

In a known method (DE-OS 29 28 084) is in • Area of the discharge table for the copper pipe, a pump provided, the suction line with the end of the as The coil present copper pipe is connected by means of a quick coupling. The blower sucks the in the area drawing agent vapors generated by the annealing device

BATH ORIGINAL

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going from inside the copper pipe ^ .-? away. The sawed off The end of the copper pipe opens into the free atmosphere, so that air can flow into the inside of the pipe and through the Decay of the drawing oil resulting in elemental carbon can burn in the area of the glow device.

In the older registration (P 30 18 036.0) the Production lengths not by a saw cut, but separated by a silhouette. As a result, a negative pressure is generated in the pipe interior by the pump and the The drawing agent vapors are completely extracted before they reach the annealing area. The end of the pipe is here not completely closed so that a small amount of air can enter the pipe interior and cause a slight Oxidation of the inner surface of the pipe results.

As a result of the length of the suction pipe, which varies over the annealing zone and the more or less gas-tight interface are in the annealing area of the production line unstable operating conditions that lead to uncontrolled carbon residues in the finished Tube remain as well as different oxide layer thicknesses' can arise.

The invention is therefore based on the object of improving the known method to the effect that now copper pipes with an approximate length over the length thick, anti-corrosive copper oxide layer can be.

In the case of a method, this task is as mentioned at the outset Kind of solved by having the gas in exactly doped Quantity by regulating the pressure or the quantity -introduced will. It is essential that a constant air pressure or oxygen partial pressure in the annealing

zone of the copper pipe is set. This can be done by be achieved that the suction pressure is an inlet side arranged pump is controlled or regulated depending on the suction length. Alternatively, a overpressure line connected on the outlet side accordingly has been monitored or controlled. If you choose the quantity control, a constant amount of air or gas is either blown in or sucked out per unit of time.

In addition to achieving constancy in the annealing range, there are other advantages that consist in the fact that the Separate the finished pipe lengths from the size of the air inlet slots created by the scissor cut from the subordinate Egg interpretation are. It can be driven with completely off-my cut if necessary. If suction is carried out, then -will the continuous change in the suction pipe length is automatically compensated for by the volume control.

The invention is explained in more detail on the basis of an exemplary embodiment shown schematically in the figure.

The copper tube 2 present in an annular collar 1 is from a waste sheet 3 peeled off and initially in a Richtrollonsatz 4 introduced. Behind the straightening roller set 4 there is a continuous resistance annealing device 5, in which the copper pipe 2 is heated to at least 600.degree. That from the continuous resistance annealing device 5 2b exiting copper pipe 2 cools slowly and is by means of an extruder 6 with an unspecified but provided known plastic jacket. Behind the Extruder 6 a flying saw 7 is arranged, which separates the sheathed copper pipe into commercial lengths. the llandc Lsläricjeri then get into a no longer representedon FördiM'ro 1.ltu'irjang and are zugelülirl in a winding device .

BATH ORIGINAL

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In the area of the drain table "3 *" there is "ezne PuWpe" <3der one Fan 8 is provided, the suction line 9 of which is connected to the end 10 of the annular collar 1 by means of a quick coupling 11 is. If there is only a short length of copper pipe 2 in the collar 1, the quick coupling "II solved, the copper tube length currently in production with a new collar by means of a permeable stopper connected with tensile strength 'and the quick coupling to the new supplied ring bundle 1 connected.

The fan 8 sucks in the heating device in the area of the resistance ^ 5 resulting pulling device holder largely from the interior of the copper pipe 2. Through this, that the cut end of the Kupferrohx-es 2 into the open atmosphere, air can flow into the inside of the pipe and the resulting elemental carbon in the Burn area of continuous glow device 5. Excess Oxygen leads to an oxide layer on the inner surface of the copper pipe 2.

So that there is always a sufficient constant amount of air inside the copper pipe 2 - this applies In particular for the area of the continuous annealing device 5 - a valve 12 is arranged in the suction line 9. This valve 12 is via one: η IchI nu: hr darcjro t.el I.to Controlled quantity regulating device or a Druckrwgulatingeinrichtung. This ensures in any case that even if the pipe length 2 in the production plant is increased inside the copper pipe, 2 the same conditions always prevail.

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Claims (1)

Cable and metal works ■ Gutehoffnungshütte Aktiengesellschaft 2-254 05/14/81 Patent claim Process for treating copper tubes, which are brought to the finished size by pressing or rolling and subsequent drawing using drawing oil and are heated after the last drawing process in order to evaporate the drawing oil and soft-annealing the tube, the drawing oil vapors from the inside by introducing a gas to be expelled, are connected end permeable to gas in which individual pipe lengths, in each case a portion of the tube length to more than 600 C, preferably by resistance or induction heating in the continuous run-through heated, and an oxidizing effect gas is introduced into the interior of the pipe length, dadurc in h that the gas in a precisely metered amount. is initiated by regulating the pressure or the amount. . ^l