DE8800081U1 - Annealing material carrier for transporting annealing material through a furnace - Google Patents

Description

an oven

The invention relates to a carrier for transporting annealing material through a furnace, with a grating having a tension yoke at one end.

It is known that metal parts that are to be thermally treated by annealing in an annealing furnace are placed on an annealing material carrier that is moved along a transport path through the annealing furnace. The annealing material carrier then reaches a quenching zone together with the annealing material, where sudden cooling takes place. The annealing material is then removed and the annealing material carrier is returned to the inlet of the annealing furnace. During these different thermal treatments, the annealing material carrier is exposed to strong temperature fluctuations, with the result that its

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Accounts:

Sal. Opoenheim jr. & Oe.. Cologne (BLZ37O3O2OO) Account No. 1O76O 'tJeutsche Bank AG. Cologne (bank code 37O 7OO 6O) Account no. 1165O18 Sostgiro KtMn (bank code 3701OO 5O) Account no. 654-5OO

different parts suffer thermal expansion and contraction.

A known annealing material carrier consists of a grid made of metal sheets that are arranged upright and connected to one another to form a grid structure. The strip-shaped metal sheets extend in a wave-like manner over the entire length of the grid. At one end of the grid there is a tension yoke, to which a hook can attach in order to guide the annealing material carrier along the transport route through the furnace and the quenching zone. In the known annealing material carriers, the grid warps as a result of the thermal stresses, whereby the contact surface of the grid can take on a wave structure and the individual strip-shaped grate bars can tear. This is mainly due to the fact that the grate bars extend over the entire length of the annealing material carrier, which causes large thermal changes in length.

The invention is based on the object of creating an annealing material carrier in which the expansion changes and material stresses caused by thermal effects are reduced and which therefore has a long service life.

This object is achieved according to the invention in that the grating consists of at least two grating parts, which are connected to one another by parallel bolts running at a mutual distance, which are inserted with play through openings in the grating parts that are aligned with one another.

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s$ In the annealing material carrier according to the invention, the grid

>■' grate divided into at least two grate parts, which

are connected to one another in an expansion-movable manner. The grate parts have molded-on tabs with openings through which the bolts are inserted, whereby the openings have a diameter such that the bolts engage in them loosely, i.e. with play. The bolts also have axial play, so that the individual grate parts and the bolts can expand in all directions. The use of two parallel bolts prevents the grating from being bent and collapsing when lifted with a crane hook. The grating therefore retains its stretched shape in all cases.

According to a preferred development of the invention, the grating has three grating parts arranged one behind the other in the transport direction, two grating parts of which are connected to one another by bars.

The middle grate section is connected to the front and rear grate sections by means of appropriate rod connections so that they can expand. In this way, the thermal stresses are reduced, particularly in the middle section of the length of the annealing material carrier. The risk of thermal breakage is greatest in this middle section.

The openings through which the bolts are stretched

are located in tabs that protrude from the respective 30 grate parts. To prevent these tabs from

can bend, are on at least one of the rods

tubular spacers are provided which grip between the tabs of the grate parts.

-A-

In the following, an embodiment of the invention is explained in more detail with reference to the drawings.

ts show:
5

Fig. 1 a top view of the grating and

Fig. 2 a section along the line II-II of
Fig.1.

The annealing material carrier shown in the drawings consists of a grating 10 made of three grating-shaped grating parts 11, 12 and 13 arranged one behind the other in the transport direction, which are made of cast material. Each of the grating parts 11, 12, 13 has longitudinal bars 14 and transverse bars 15. At some intersection points of the bars 14 and 15, vertical threaded holes 16 are provided, into which pillars (not shown) can be screwed in order to produce tiered gratings with spacer bushings in which several gratings are arranged one above the other.

The grate part 11, which is located at the front in the direction of transport, has at its rear end lugs 17 which protrude to the rear and are arranged as an extension of the longitudinal bars 14 and which are formed integrally with the grate part 11. The middle grate part 12 has fork-shaped pivot lugs 18 which engage around the lugs 17. In both lugs 17 and 18, aligned holes 19 are provided through which bolts 20, 21 are inserted. These bolts 20 and 21 have radial play in the holes 19. The bolts 20 and 21 are arranged at a horizontal distance from one another so that they can be connected to the lugs.

17,18 form a connection between the grate parts 11 and 12, which does not allow the grate parts to bend against each other, but allows play to compensate for thermal expansion and contraction.

At the rear end of the middle grate part 12, further double tabs 18a protrude from it, between which a tab 17a, which protrudes from the front end of the rear grate part 12, engages. Holes 19a arranged one behind the other in the transport direction are also provided in the tabs 17a and 18a, through which bolts 20a and 21a are inserted in the same way as is the case with bolts 20 and 21. The bolts 20, 21 and 20a, 21a each extend over the entire width of the grating 10 and at their ends there are heads 22 which do not fit through the openings 19, 19a, so that the bolts cannot be pulled out of the tabs. All three grate parts 11, 12, 13 are connected to one another in an expandable manner by the bolt pairs 20, 21; 20a, 21a. The middle grate part 12 is significantly shorter than the front grate part 11 and the rear grate part 13, which have approximately the same length.

The tension yoke 23 is attached to the front end of the front grate part 11. For this purpose, lugs 24 are provided as an extension of the longitudinal bars 14, which are overlapped by fork-shaped double lugs 25 of the tension yoke 23. On each side there are two bolts 26 and 27, which are inserted through openings 28 of the lugs 24, 25 and secured against being pulled out by heads 30, 31. The two side

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The two regions of the tension yoke 23 are bridged by a central part 32, which can be engaged by a tension member in order to pull the grating 10 through an annealing furnace. The described arrangement connects the tension yoke 23 to the first grating part 11 in a flexible manner, but prevents the tension yoke 23 from tipping over.

On the bolts 21, 21a and 27, between two double tabs 18»18a and 25, there is a sleeve-shaped spacer 33 which prevents the arms of the double tabs from bending. The spacer 33 is arranged on the bolt 21, 21a and 27 which, in relation to a double tab, is located furthest outward.

Claims (6)

EXPECTATIONS 1. Annealing material carrier for transporting annealing material through a furnace, with a grid (10) having a pulling yoke (23) at one end,
characterized in that the grating (10) consists of at least two grating parts (11,12,13), which are connected by mutual Parallel bolts (20,21;20a, 21a) running at a distance are connected to one another and pass with play through openings (19;19a) in the grate parts (11,12,13) that are aligned with one another. 2. Annealing material carrier according to claim 1, characterized in that the grating (10) has three grate parts (11, 12, 13) arranged one behind the other in the transport direction, of which two grate parts (11, 12; 12, 13) are connected to one another by the bars (20, 21; 20a, 21a). 3. Annealing material carrier according to claim 1 or 2, characterized { indicates that at least one of the bars (21;21a) has tubular spacers (33) which are arranged between tabs (17,18;18a,18a) of the grate parts are arranged. 4. Annealing material carrier according to one of claims 1 to 3, characterized in that the tension yoke (23) is connected to a grate part (11) by two groups of two bolts (26, 27) arranged at a mutual distance from each other, which pass with play through aligned openings (28) of this grate part (11) and the tension yoke (23). • · I . >I t· *·· ti, ■ > &igr; ■ · 5. Annealing material carrier according to one of claims 1 to 4, characterized in that the grate parts (11, 12, 13) have vertical threaded holes (16) at the intersection points of the grid bars (14, 15) into which pillars can be screwed. 6. Annealing material carrier according to one of claims 1 to 5, characterized in that one of the grate parts (12) has fork-shaped double tabs (18, 18a) between which single tabs (17, 17a*) of the adjacent grate part (11, 13) protrude.