RU141915U1 - ELECTRIC FURNACE FOR VERMICULITE FIRING - Google Patents

Abstract

An electric vermiculite roasting furnace containing baking sheets made of refractory material, installed at an angle to each other to ensure that the raw material is poured during the roasting process from one to another and having heaters made in the form of tapes mounted on a rib and placed under the covers on the surfaces of the baking sheets are longitudinal, while the heaters are mounted on mounting heads having parallel faces to ensure their parallel installation, and the mounting heads themselves are mounted on panels, GOVERNMENTAL in the backs of the trays, wherein the trays are provided with hinges and configured to change its position from oblique to horizontal, and that the fastening head formed with notches for the recess in the assembled fastening kits.

Description

The utility model relates to the field of building materials, namely, equipment for the production of expanded vermiculite.

Known furnace for firing vermiculite (options) [RU No. 85993, IPC F27B 15/00, published 08/20/2009], including baking sheets made of refractory material, installed in relation to each other at an angle that ensures the pouring of raw materials during firing from one on the other and equipped with electric heaters located on the surfaces of the baking sheets.

Common features of the claimed utility model with an analogue are baking sheets made of refractory material, installed at an angle to each other, which ensures that the raw material is poured during firing from one to another and equipped with electric heaters located on the surfaces of the baking sheets.

The specified furnace has the following disadvantages. The baking sheets are not hinged and cannot change their inclined position, which complicates the replacement of blown electric heaters, and the electric heaters located on the surfaces of the baking sheets are fixed with insulators, which complicates the disassembly and replacement of blown electric heaters and their parallel installation on the refractory surface after replacement .

Also known is an electric furnace for firing vermiculite (RU No. 128706, IPC F27B 15/14, published 05/27/2013), containing baking sheets made of refractory material and installed in relation to each other at an angle that ensures the filling of the raw material during firing from one on the other, and electric heaters, placed under the covers on the surface of the baking sheets, made in the form of ribbons mounted on a rib, electric heaters are made with a variable cross section and are mounted on mounting heads with parallel faces.

Common features of the analogue with the claimed utility model are baking sheets made of refractory material and installed in relation to each other at an angle that ensures the pouring of raw materials during the firing process from one to the other, and electric heaters placed under the covers on the surface of the baking sheets, made in the form of tapes with a variable cross-section, mounted on a rib and mounted on mounting heads with parallel faces.

The specified furnace has the following disadvantages. The baking sheets are not hinged and cannot change their inclined position to horizontal, which significantly complicates the replacement of burned-out electric heaters, and electric heaters mounted on mounting heads with parallel faces do not have grooves for removing mounting sets - studs, pressure plates and nuts in assembled form , which complicates and increases in time the disassembly and replacement of burned-out heaters.

The prototype is an electric vermiculite roasting furnace (RU No. 108128, IPC F27B 15/14, published September 10, 2011), containing baking sheets made of refractory material and installed in relation to each other at an angle that ensures that the raw material is poured during firing from one on the other, equipped with heaters made in the form of ribbons, mounted on a rib and placed longitudinally under the covers on the baking sheet surface, electric heaters are mounted on mounting heads having parallel faces to ensure their parallel noy installation and fixing themselves head placed on the quick release panels installed in the slots on the backs of the trays.

Common signs of the claimed utility model with the prototype are baking sheets made of refractory material and installed in relation to each other at an angle that provides the pouring of raw materials during the firing process from one to another, equipped with heaters made in the form of tapes mounted on a rib and placed under the covers on the surface of the baking sheets longitudinally, the heaters are mounted on mounting heads having parallel faces to ensure their parallel installation, and the mounting heads themselves are placed on firs installed at the rear of the trays.

The disadvantage of the prototype is that the replacement of a quick-detachable panel with mounting heads and heaters is acceptable for small ovens with narrow and short baking sheets up to 800 mm wide and 300 mm long, i.e. then, when the weight of the quick-detachable panel together with heads and heaters does not exceed 25-30 kg. On large industrial furnaces, the dimensions and weight of the baking sheets of which are much larger, it is advisable to replace one heater, having previously installed the baking sheet in a horizontal position. But the prototype trays are not equipped with hinges and cannot change their inclined position to horizontal, which greatly complicates both the replacement of the quick-detachable panel as a whole and the replacement of individual burned out heaters.

In addition, the prototype electric heaters are mounted on mounting heads that do not have grooves for the extraction of mounting sets - studs, pressure plates and nuts in assembled form only with a slight weakening of their tightening. Such a need arises during the operation of furnaces in order to replace not only electric heaters, but also pressure plates, since in places of contact with electric heaters during prolonged operation and high temperature diffusion transfer of one metal to another occurs, leading to damage to the original (even) surfaces . When installing a new electric heater due to irregularities on the surfaces of the pressure plates, a loose contact is formed, this connection, despite the addition of high-temperature conductive paste, gradually heats up, local overheating of the electric heater occurs and it burns out.

The design of the fixing heads without grooves for removing the assembled fastening sets (studs, pressure plates and nuts) requires the complete unscrewing of the nuts and the removal of the studs through the holes in the fixing heads. When disassembling a threaded connection that has worked at high temperature, a complete jamming of the thread often occurs, requiring sawing the studs and discarding unsuitable fasteners. This significantly complicates and lengthens in time the disassembly of the fastening and the replacement of electric heaters and leads to a significant reduction in the maintainability of the furnace as a whole. Increasing the time for disassembling the fastening and replacing the heaters leads to downtime and, as a result, to a decrease in the operational productivity of the furnace.

The objective of the claimed utility model is to increase the maintainability of an electric furnace for firing vermiculite and increase its operational performance.

The technical result of the utility model consists in increasing the maintainability of an electric furnace for burning vermiculite due to the possibility of installing baking sheets for repair in a horizontal position and through the use of fixing heads for fixing heaters with grooves for removing mounting sets - studs, pressure plates and nuts in assembled form, and in increasing the operational productivity of the furnace by reducing the time to replace electric heaters.

The specified technical result is achieved in that the electric furnace for firing vermiculite, contains baking sheets made of refractory material and installed in relation to each other at an angle that provides the pouring of raw materials during the firing process from one to another, equipped with heaters made in the form of tapes installed on the rib and placed longitudinally under the covers on the surface of the baking sheets, the heaters are mounted on mounting heads having parallel faces to ensure their parallel installation, and fixing heads are mounted on panels, placed at the rear of the trays.

The difference between the claimed utility model and the prototype is that the baking sheets are hinged and have the ability to change their position from inclined to horizontal, and the mounting heads are made with grooves for recessing the assembled fastening sets - studs, pressure plates and nuts.

The presence of distinctive features allows us to conclude that the claimed utility model meets the patentability condition of “novelty”.

In FIG. 1 shows a diagram of an electric furnace for firing vermiculite.

In FIG. Figure 2 shows a baking sheet: a side view with a local section and a diagram of the replacement of the electric heater and mounting kit - studs, pressure plates and nuts.

The electric vermiculite kiln shown in FIG. 1, contains a dispenser of vermiculite concentrate 1, the furnace body 2, baking sheets 3 with hinges 4, resting on the walls 5 of the furnace body 2. The baking sheets 3 in the working position are installed with respect to each other at an angle that ensures the spreading of expanded vermiculite from one to another. Mounting heads 6 are placed on the rear of the baking sheets 3. Heaters 7 are located longitudinally on the surfaces 8 of the baking sheets 3, for example, laid out of refractory bricks. The covers 9 are mounted on baking sheets 3 and together with them form firing spaces enclosed between them.

The baking sheet (Fig. 2) contains a frame 1 with refractory material 2 made of refractory bricks, transverse angles 3 and a two-way hinge 4. A fixing head 5 mounted on one of the corners 3 in the back of the baking sheet through electrical insulating spacers 6 with the help of a stud 7 and nuts 8 has slots 9 and a fastening set inserted into them, consisting of studs 10, pressure plates 11 and nuts 12. On the refractory material 2, thanks to the parallel faces of the fastening heads 5, heaters 13 located parallel to each other are located. there is a covering metal layer 14 and a heat-insulating layer 15.

The heaters 13 have a variable cross-section (Fig. 2). At sites above oversleeping vermiculite zones a, b and c (Fig. 1) the cross section of electric heaters 13 is increased, compared to the normal cross-section through the rest length (FIG. 2). Between the enlarged and normal sections there is a section with a variable section (Fig. 2).

An electric furnace for burning vermiculite works as follows.

Vermiculite concentrate is supplied by dispenser 1 (Fig. 1) through the tray to the zone of pouring the upper pan 3. The intumescent vermiculite moves under the action of gravity along the refractory surfaces 8 between the heaters 7 of the pan 3, where it is exposed to the heat radiation of the heaters 7 in the firing spaces. As it moves vermiculite is expanded and poured from one baking sheet 3 to another and in the lower part of the body 2 of the electric furnace, ready-made expanded vermiculite comes out of it.

The heaters 13 (Fig. 2) in areas with a normal cross-section are heated to a temperature of 700-750 ° C and the main firing process takes place in this zone. In areas with an increased cross section, there is no vermiculite flow, therefore, at the same current strength, the temperature radiation is much less.

In the event of a burnout of one of the heaters 7, for example, on the lower baking sheet 3 (Fig. 1), the electric furnace for firing vermiculite is disconnected from the mains and the casing doors open (not shown in Fig.). After cooling the oven for 25-35 minutes, the lower pan 3 is rotated in the hinge 4 to a horizontal (repair) position and fixed (Fig. 1, rotated). Using wrenches (Fig. 2), loosen the nuts 12 and both fastening sets, each consisting of two studs 10, four nuts 12 and four pressure plates 11, two external and two internal (rear view of the head with the mounting kit) are removed from the grooves 9 adjacent mounting heads 5, on which the heater 13 located between them was fixed. Into the grooves 9 (Fig. 2) of the disassembled mounting heads 5, two new mounting sets are inserted, each consisting of two studs 10, four nuts 12 and four pressure plates 11 and then insert a new heating Yelnia element 13.

The removed mounting kits are inspected, repaired or rejected in whole or in part.

Baking sheet 3 (Fig. 1) is returned to the inclined (working) position and fixed.

Then the electric furnace for firing vermiculite is again connected to the network and after reaching the steady-state thermal regime, the concentrate is dispensed by dispenser 1 (Fig. 1).

Thus, the technical result of the utility model is achieved, which consists in increasing the maintainability of the electric furnace for burning vermiculite due to the possibility of installing baking sheets for repair in a horizontal position and the use of mounting heads for fixing heaters with grooves for removing mounting sets - studs, pressure plates and nuts in the assembled form and in increasing the operational productivity of the furnace by reducing the time to replace heaters.

Claims (1)

An electric vermiculite roasting furnace containing baking sheets made of refractory material, installed at an angle to each other to ensure that the raw material is poured during the roasting process from one to another and having heaters made in the form of tapes mounted on a rib and placed under the covers on the surfaces of the baking sheets are longitudinal, while the heaters are mounted on mounting heads having parallel faces to ensure their parallel installation, and the mounting heads themselves are mounted on panels, GOVERNMENTAL in the backs of the trays, wherein the trays are provided with hinges and configured to change its position from oblique to horizontal, and that the fastening head formed with notches for the recess in the assembled fastening kits.

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