GB2123040A

GB2123040A - Method of and apparatus for chilling and hardening heated pipes

Info

Publication number: GB2123040A
Application number: GB08316935A
Authority: GB
Inventors: Wolfgang Kretzschmann; Jurgen Schulz; Josef Holtermann
Original assignee: Mannesmann AG
Current assignee: Vodafone GmbH
Priority date: 1982-07-07
Filing date: 1983-06-22
Publication date: 1984-01-25
Also published as: IT1169441B; JPS599126A; GB8316935D0; DE3225846C2; FR2529908A1; IT8321823A0; DE3225846A1; GB2123040B

Abstract

A pipe, heated to 850 to 1050 DEG C, is chilled/hardened in an oil bath (1) by being moved in said oil (3) in the manner of a pendulum (e.g. through an angle of 40 DEG in one direction and then through the same angle in the reverse direction, and so on) whilst oil is caused to flow through the pipe. The pendulum-like-motion causes turbulence of the oil inside the pipe and also around the outside of the pipe and this ensures good heat dissipation. The pipe (5) is caused to move in the manner of a pendulum by star-like devices (2) carried by a shaft (10) on which is mounted a flushing device (4, 7, 8) which is connected to a supply of oil. The flushing device can be moved along the shaft in order to apply a flushing funnel at the free end of said device to one end of the pipe. <IMAGE>

Description

SPECIFICATION Method of and apparatus for chilling and hardening heated pipes This invention relates to a method of chilling and hardening the inner and outer surfaces of pipes, heated to 850 to 1 0500C, in an oil bath, and an apparatus for carrying said method into effect.

It is known to chill heated pipes by submerging them in an oil bath but this method results in longitudinal deformation of the pipes which necessitates re-alignment.

It is also known to pass pipes into tanks and to transport the pipes via a star-type rotating device.

Although this method produces relatively good results as regards the outer surfaces and also prevents further longitudinal distortion of the pipes, the quality of the inner surface of the pipes is unsatisfactory.

It is also known to flush the interior of pipes whilst they are at rest but the disadvantage of this method of treatment is the resultant poor external quality of the pipes.

The aim of the invention is to provide a method of and an apparatus for chilling and hardening the inner and outer surfaces of heated pipes which will eliminate these disadvantages.

In accordance with a first aspect, the present invention consists in a method of chilling and hardening the inner and outer surfaces of a pipe, heated to 850 to 1 0500C, in an oil bath, comprising the step of moving said pipe in the manner of a pendulum in the oil bath and simultaneously causing oil to flow through said pipe, whereby turbulence is imparted to the oil inside and ouside the pipe with resultant optimum heat dissipation. The method results in substantial improvement of hardening.

In accordance with a second aspect, the present invention consists in apparatus for carrying out the method described in the preceding paragraph, comprising a drive system drivingly connected to a shaft which extends along an oil bath and which carries at least two star-type devices which are spaced from one another axially of the shaft for the engagement of a pipe which is to be chilled and hardened in the oil; and a flushing device connectible to one end of said pipe in order to permit oil to be supplied to the interior of said pipe; said drive system being operable to cause said devices and the pipe engaged thereby to move in the oil bath in the manner of a pendulum.

The flushing device referred to in the preceding paragraph may be mou. ted on a bearing which is slidable in each of two opposite directions along said shaft and the flushing device may be connected to a stationary oil supply line by means of lines having articulated connections with said supply line and with the flushing device.

The flushing device preferably includes a funnel which is applied to one end of the pipe.

A lifting device may be arranged at one end of the oil bath for the tilting of a pipe in order to empty the oil out df said pipe at the end of the chilling/hardening of said pipe; each of said startype devices may have a respective one of a number of connecting member connected thereto for the establishment and breaking of a connection between the flushing device and the star-type device; a pneumatic cylinder/piston arrangement will preferably be provided for the displacement of said bearing along said shaft; and said funnel will preferably be rotatable and exchangeable.

One embodiment of the apparatus in accordance with the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a cross-section showing the apparatus in the pipe-receiving position; Figure 2 is a cross-section of the apparatus in the condition thereof in which a pendulum-like motion begins to be imparted the pipe; Figure 3 is a longitudinal section through that part of the equipment which includes the flushing device; and Figure 4 shows the position of the star-type rotatable device for changing and adjusting the height of the flushing funnel.

Referring to the drawing, in the centre of a right cylindrical oil tank 1, there is arranged a shaft 10 which is supported upon multiple bearings and which is provided with at least two star-type rotatable devices 2 which are spaced from one another axially of said shaft. The shaft is driven by an external drive system 12 (see Figure 3) and the tank 1 has regularly spaced elements 6 secured to its inner surface. A flushing device, including a flushing funnel 4 which can be applied to one of a heated pipe 5 which is to be chilled, is arranged on a sliding (slidable) bearing 9 located on the shaft and is connected to a stationary oil supply line 8 by means of lines which can be moved via articulated connections 7.A connecting member 11 serves to couple the flushing device to the startype rotating device 2 in order to drive the flushing funnel 4 which is in contact with the end of the pipe.

The drive system 12, in a preferred embodiment, is hydraulic and the star-face type device 2 operate via gears and racks.

A pneumatic cylinder/piston arrangement 13 is provided for the displacement of the bearing 9 which supports the flushing device (see Figure 3).

The funnel 4 is rotatable and exchangeable.

The device hereinbefore described is to be operated in order to carry out the following method: A pipe 5 which is to be chilled and which is to be loaded into the device 2 is firstly pivoted into the oil bath 3 by anticlockwise rotation until the flushing funnel 4 can be applied to the adjacent pipe end by displacing the sliding bearing 9 and the supported flushing device towards said pipe end. As a result of short-duration angular movement of the shaft 10 about its axis in each of two opposite directions, during which movements the devices 2 are moved back and forth through an angle of approximately 400, the pipe 5 is moved through the oil in the manner of a pendulum. At the same time, the action of the flushing device commences in order to cause oil to flow through the interior of the pipe.Thus, the pendulum-like movement of the pipe 5 through the oil creates a turbulence which is enhanced by the presence of the elements 6, and the pendulum-like movement of said pipe will also cause turbulence of the oil which is flowing through the pipe; in this way, the outer and inner surfaces of the pipe 5 are brought into extremely good contact with the chilling fluid.

Following the chilling and hardening step described in the preceding paragraph, the flushing device including the flushing funnel 4 is moved away from the end of the pipe 5 and at the same time the connecting member 11 is detached from the flushing device. The treated pipe 5 is then conveyed into a twelve-o'clock position by means of the devices 2, and is lifted and tilted by a pipe lifting device (which has not been shown but which is arranged above one of the end zones of the oil tank 1) in order that the oil may be rapidly discharged from the interior of the pipe.

Thereafter, the pipe is lowered again and the devices 2 are turned further in order to convey the pipe to the discharge end of the apparatus, whereupon the devices 2 are turned back into their pipe-receiving position.

Claims

1. Method of chilling and hardening the inner and outer surfaces of a pipe, heated to 850 to 1 0500C, in an oil bath, comprising the step of moving said pipe in the manner of a pendulum in the oil bath and simultaneously causing oil to flow through said pipe, whereby turbulence is imparted to the oil inside and ouside the pipe with resultant optimum heat dissipation.

2. Apparatus for carrying out the method claimed in Claim 1, comprising a drive system drivingly connected to a shaft which extends along an oil bath and which carries at least two star-type devices which are spaced from one another axially of the shaft for the engagement of a pipe which is to be chilled and hardened in the oil; and a flushing device connectible to one end of said pipe in order to permit oil to be supplied to the interior of said pipe; said drive system being operable to cause said devices and the pipe engaged thereby to move in the oil bath in the manner of a pendulum.

3. Apparatus as claimed in Claim 2, wherein the flushing device is mounted on a bearing which is slidable in each of two opposite directions along said shaft and the flushing device may be connected to a stationary oil supply line by means of lines having articulated connections with said supply line and with the flushing device.

4. Apparatus as claimed in Claim 2 or Claim 3, wherein the flushing device includes a funnel which is applied to one end of the pipe.

5. Apparatus as claimed in any one of Claims 2 to 4, wherein a lifting device is arranged at one end of the oil bath for the tilting of a pipe in order to empty the oil out of said pipe.

6. Apparatus as claimed in any one of Claims 2 to 5, wherein each of said star-type devices has a respective one of a number of connecting member connected thereto for the establishment and breaking of a connection between the flushing device and the star-type device.

7. Apparatus as claimed in Claim 3 or in any of Claims 4 to 6 when appended to Claim 3, wherein a pneumatic cylinder/piston arrangement is provided for the displacement of said bearing along said shaft.

8. Apparatus as claimed in Claim 4 or in any of Claims 5 to 7 when appended to Claim 4, wherein said funnel is rotatable and exchangeable.

9. Apparatus for chilling and hardening, in an oil bath, a pipe which has been heated to 850 to 1 0500C, said apparatus being constructed, arranged and adapted to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

10. Method of chilling and hardening the inner and outer surfaces of a pipe, heated to 850 to 1 0500C, in an oil bath, substantially as hereinbefore described with reference to the accompanying drawings.

11. Any features of novelty, taken singly or in combination, of the embodiments of the invention hereinbefore described with reference to the accompanying drawings.