US3291954A

US3291954A - Method of and apparatus for electroinductively heating metal billets

Info

Publication number: US3291954A
Application number: US353452A
Authority: US
Inventors: Scheffler Friedrich
Original assignee: Deutsche Edelstahlwerke AG; AEG AG
Current assignee: Deutsche Edelstahlwerke AG; AEG AG
Priority date: 1963-09-28
Filing date: 1964-03-20
Publication date: 1966-12-13
Anticipated expiration: 1983-12-13
Also published as: AT246871B; DE1215187B

Description

Dec. 13, 1966 F. SCHEFFLER 3,291,954

METHOD OF AND APPARATUS FOR ELECTRO-INDUCTIVELY HEATING METAL BILLETS Filed March 20, 1964 2 Sheets-Sheet l Dec. 13, 1966 F. SCHEFFLER 3,291,954

METHOD OF AND APPARATUS FOR ELECTRO-INDUCTIVELY HEATING METAL BILLETS Filed March 20, 1964 2 Sheets-Sheet 2 United States Patent Germany, and Allgemeine Elektricitats-Gesellschaft, Berlin-Grunewald, Germany Filed Mar. 20, 1964, Ser. No. 353,452 Claims priority, application Germany, Sept. 28, 1963, D 42 582 11 Claims. oi. 219--10.69)

The present invention relates to .a method of and apparatus for electro-inductively heating metal billets.

When metal billets are heated it is often desirable that the hotbillets should be ready at given intervals for feeding a hot working machine or the like without interruption. This requirement is generally impossible to satisfactorily by using a furnace in which the billets are heated by gas, oil or electric resistors. It has therefore already been proposed to interpose in the supply line between such a furnace and the hot working machine supplementary heating equipment which can be controlled in synchronism with the working cycle of the hot working machine. The use of induction heating equipment has already been proposed for this purpose.

The present invention concerns plants for electro-inductively heating metal billets which are to be supplied to hot working machines or the like at intervals which synchronise with a prescribed working cycle. The proposed plant is distinguished by its particularly convenient construction which is extremely compact for solving the problem in question. The invention provides a billet-transporting roller bed with tiltable sections above which the inductors are located outside the path of the roller bed. Alongside each tiltable section of the roller bed is a stand for supporting one inductor. The stands are also equipped with a slideway for a billet loading slide which is adapted to push the billet up the tilted roller bed section int-o the inductor interior .and to lower the same out of the inductor. Whilst the tiltable roller bed section returns into the horizontal the slide retains the billet in the inductor.

The proposed plant permits the several inductors to be independently loaded and unloaded again without impeding the continued flow of billets along the roller bed. It is thus possible with due regard to the required heating and reheating times that may be required to adjust the intervals at which the billets heated to hot working temperature, are delivered in synchronism with the working cycle of a following hot working machine. The roller bed need merely be provided with a sufiicient number of inductors to permit operation in conformity with the particular circumstances and factors that govern the working cycle of the production line. Moreover, a single preheating furnace may be associated with a plurality of or with two roller beds arranged side by side and billets may be delivered to the several beds in rotation, for instance by suitable gating means.

A preferred embodiment of the invention is illustratively shown in the drawings in which FIG. 1 is a perspective view of a live roller bed,

FIG. 2 is a vertical section of the live roller bed directly behind one of the tipping sections,

FIG. 3 is a side elevation of an inductor stand and FIG. 4 is a similar side elevation of a stand showing the loading slide and the billet in loaded or unloaded position.

An elongated base 1 carries a live roller bed 2, the several rollers being driven either individually or in groups in a manner that is well understood. Sections 3 of the roller bed are adapted to tilt on trunnion bearings 4. The

3,291,954 Patented Dec. 13, 1966 tiltable sections are likewise fitted with rollers which may be driven singly or in groups. Conveniently facilities are provided for driving the rollers in the tiltable sections 3 at a speed which differs from that of the rollers in the rest of the live roller bed.

Each tiltable section is equipped with an interceptor 5 which can be tiltably raised on pivots 6. In chain dot outlines an interceptor is shown in raised position at 5 in FIG. 2. The purpose of the interceptor is to stop a billet travelling along the roller bed when it has been conveyed on to the respective tiltable section. An intercepted billet is shown in chain dot lines at 7.

Alongside each tiltable section 3 is a stand '8 which carries an inductor 9. The inductor is so disposed that its opening .10 aligns with the tiltably raised roller bed section 3.

Stand 8 also carries a slideway 11 for a billet loading slide 12. The slideway is parallel to the axis of the associated inductor 9. The billet loading slide 12 has a lateral arm 14 with a pusher finger 13.

In FIG. 3 the billet loading slide 12 is shown in its upper position in which it holds a billet 7 inside inductor 9 where the billet can be heated to a required temperature. FIG. 3 also illustrates that the tiltable roller bed section 3 drops back int-o alignment with the rest of the roller bed during this heating operation, so that the continuity of the roller bed is restored.

In FIG. 4 the loading slide .12 is shown in its bottom position. It will be seen that the tiltable section 3 of the bed can then clear the slide 12.

The illustrated arrangement which is intended for reheating metal billets functions as follows:

In FIG. 1 it will be understood that a furnace is located at the right hand charging end of the roller bed. This may be, for example, an electric resistance heating furnace for heating say steel billets for hot working to a temperature of something like 600. Each billet, after having reached this temperature, is discharged on to the roller bed shown in FIG. 1. It is assumed that the billet has been propelled to the first inductor at the left hand forward end of the bed in FIG. 1. Here the billet 7 is stopped on the associated tiltable roller bed section by the interceptor 5. The reduce the impact the billet may be slightly braked by the rollers in the tiltable section revolving at a slower speed than the rollers in the rest of the bed. The section 3 is then tilted into the position illustrated in FIG. 4. This is the same position as that which the tiltable section is seen to occupy at the middle stand in FIG. 1. The pusher finger 13 of the billet loading slide 12 can now be applied to the end of the billet to raise the same into the interior of the inductor 9. The final loading position of the slide 12 is that shown in FIG. 3. This is the billet heating position which is also seen to have been established in the distant inductor on the right in FIG. 1. The tilted roller bed section returns into the horizontal whilst the interceptor 5 is raised into position 5. The next billet discharged by the preheating furnace can therefore now pass underneath the loaded inductor to another stand in which the inductor happens to be ready to receive it. Alternatively, a heated billet can be carried past the loaded inductor stand to the hot working machine.

When the billet has been .sufiicientl-y heated by the inductor, the tiltable section is again tilted to receive the heated billet and the slide is lowered again to the position shown in FIG. 4. The tilted section is again returned into line with the bed, the interceptor which has been rendered operative prior to tilting the said section is again rendered inoperative and the billet heated by the inductor is carried on by the bed.

The heating times during which the loading slides remain in heating position, the tilting deflections of the tiltable roller bed sections, the raising and lowering of the inte-rceptors and the speed of travel on the roller bed can be suitably synchronised by electric control means comprising timing relays and so forth in a manner well known to the art.

'What I claim is:

v1. Apparatus for electro-indnctively heating metal billets which are required to be delivered to hot-working apparatus or the like in synchronism with a predetermined working cycle, comprising a billet-transporting roller bed; said bed comprising a plurality of sections each tiltable into an inclined position; an inductor located above each tiltable section outside the path of travel of the billets on the bed; and means for conveying a billet on a tilted section along said section and into cooperation with the inductor associated therewith and for maintaining the said co-operation while the said tilted section is returned into alignment with the bed to allow another billet to be transported past the said inductor.

2. Apparatus according to claim 1, comprising a displaceable billet-interceptor on each said tiltable rollersection adapted to be displaced into intercepting position when the said section is to be tilted with the intercepted billet and to be withdrawn when it is desired that another billet shall pass oil. the said section when this is co-linear with the bed.

3. Apparatus according to claim 1, comprising a pivoted billet-interceptor on each tiltable section.

4. Apparatus for electr-o-inductively heating metal billets which are required to be delivered to a hot-working machine or the like in synchronism with a predetermined working cycle, comprising a billet-transporting roller bed, said bed comprising a plurality of sections each tiltable into an inclined position, and inductor and a support therefor alongside each tipping section, a billet loading slide, and means for guiding said slide for movement on said support, said slide being adapted to push a billet up a tilted .section into the interior of the saidind-uctor and to hold the billet in the interior of the inductor whilst the tilted section returns into alignment with the rest of the roller bed, said slide being operable to lower the heater billet from the inductor to the bed.

5. Apparatus according to claim 1, comprising means for driving rollers of the bed for transporting the billets.

6. Apparatus according to claim 1, in which the bed comprises tiltable and non-tiltable sections and means for driving rollers on the bed for transporting the billets.

7. Apparatus according to claim 1, in which the bed comprises tiltable and non-tiltable sections, means for driving rollers of non-tiltable sections of the bed, means for driving rollers of the tiltable sections of the bed and means for controlling the speed of notation of the rollers on at least the tiltable sections of the bed.

8. Apparatus according to claim 1, in combination with a pre-heating furnace.

9. The method of electr-o-ind-uc'tively heating metal billets which comprises transporting billets along a roller bed provided with a plurality of sections each tiltable into an inclined position periodically tilting a said section with a billet located thereon, and displacing the said billet along said section into an induction heater, retaining the said billet in the said heater and returning the.

said tilted section into line with the bed and causing at least one further billet to pass along and beyond the said returned section while the said first billet remains in the heater and lowering said first billet when heated sulficiently again onto the bed in predetermined timed relation to the travel of billets along the bed and delivering the heated billet and hot-working it.

10. The method according to claim 9, in which a plurality of said sections are provided and a said inductor is associated with each said section and while a billet is being heated in the heater associated with a first said section a further billet traverses this first section along the bed, said further billet being intercepted on a second tiltable section of the bed and said second section tilted and said further billet displaced into the inductor associated with the said second section.

11. The method of .electro-inductively heating metal billets which comprises transporting billets by means of a roller bed provided with a plurality of sections each tiltable into an inclined position, periodically tilting a said section with a billet located thereon and displacing the said billet along said section into an induction heater, retaining the said billet in the said heater and returning the said tilted section into line with the bed and causing at least one further billet to pass along and beyond the said returned section whilst the first said billet remains in the heater, again tilting the said section and receiving the heated billet from the inductor thereon and again returning the said section into line with the bed and causing the said heated billet to be carried on by the bed to a hot Working machine.

Claims

1. APPARATUS FOR ELECTRO-INDUCTIVELY HEATING METAL BILLTS WHICH ARE REQUIRED TO BE DELIVERED TO HOT-WORKING APPARATUS OR THE LIKE IN SYNCHRONISM WITH A PREDETERMINED WORKING CYCLE, COMPRISING A BILLER-TRANSPORTING ROLLER BED; SAID BED COMPRISING A PLURALITY OF SECTIONS EACH TITLTABLE INTO AN INCLINED POSITION; AN INDUCTOR LOCATED ABOVE EACH TILTABLE SECTION OUTSIDE THE PATH OF TRAVEL OF THE BILLETS ON THE BED; AND MEANS FOR CONVEYING A BILLET ON A TILTED SECTION ALONG SAID SECTION AND INTO COOPERATION WITH THE INDUCTOR ASSOCIATED THEREWITH AND FOR MAINTAINING THE SAID CO-OPERATION WHILE THE SAID TILTED SECTION IS RETURNED INTO ALIGNMENT WITH THE BED TO ALLOW ANOTHER BILLET TO BE TRANSPORTED PAST THE SAID INDUCTOR.