AU619194B2 - Arrangement for cleaning surfaces of a wool chamber in the manufacture of mineral wool - Google Patents

Description

AU-AI-19567/ 88 6 1 949 WORLD INTELLECTIAL PROPETY 0RGANIZATIO\ Inernational Hureau INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (51) International Patent Classification 4 (11) International Publication Number: WO 88/ 10242 C03B 37/04, 37/05 Al (43) International Publication Date: 29 December 1988 (29.12.88) (21) International Application Number: PCT/FI88/00095 (81) Designated States: AT (European patent), AU, BE (Eu.

ropean patent), CH (European patent), DE (Euro- (22) International Filing Date: 13 June 1988 (13.06,88) pean patent), DK, FR (European patent), GB (European patent), IT (Eui pean patent), JP, LU (European patent), NL (European patent), NO, SE (Euro.

(31) Priority Application Number: 872747 pean patent), US.

(32) Priority Date: 18 June 1987 (18,06.87) Published (33) Priority Country: FI With international search report, (71) Applicant (for all designated States except US): OY PARTEK AB [FI/Fl]; SF-21600 Pargas A 0. J. P. 16 MAR 1989 (72) Inventor; and Inventor/Applicant (for US only) NURMI, Tom, Emil, Edgar [FI/Fl]: Kvarnbacksv'lgen 5, SF-21600 PargasAUST

AUSTRALIAN

(74) Agent: BERGGREN OY AB; P.O, Box 16, SF-00101 19 JAN 1989 Helsingfors (FI).

PATENT

OFFICE

(54) Title: ARRANGEMENT FOR CLEANING SURFACES OF A WOOL CHAMBER IN THE MANUFACTURE OF MINERAL WOOL 6 2 61 (57) Abstract The invention relates to an arrangement for cleaning a wool chamber in the manufacture of mineral wool. In the manufacture of mineral wool a binder is added to the stream of fibers which is deflected towards the wool chamber and said binder deposits itself in fine droplets on the fibers. The binder-loaded fibers which touch against the walls and roof of the wool chamber adhere to them because the binder hardens upon contact with the hot surfaces. Gradually a hard deposit of binder and fibers is formed upon the walls. According to the invention cleaning of the walls is substantially simplified by means of making the walls 9) and/or the roof of a double-walled construction, perforating the inner walls and applying a reduced pressure in the cavity between the walls and holding a detachable lining against the inner walls by means of suction. When said detachable lining has become coated with deposits of binder and fibers to a certain thickness production is halted and the reduced pressure is broken off, whereon the detachable lining together with the deposits falls off and a new detachable lining or linings respectively are applied to the perforated walls WO 88/10242 PCT/FI8K/00095 Arrangement for Cleaning Surfaces of a Wool Chamber in the Manufacture of Mineral Wool The invention relates to an arrangement for cleaning the inner surfaces of a wool chamber for the manufacture of mineral wool. iacgdance with the pr-am3-bl- te h e- In the manufacture of mineral wool a melt of mineral raw material is caused to run to a fibrillation unit. This can consist of a series of rapidly rotating cylinders on which the melt runs down over the peripheral surfaces and is thrown out by these and stretched during the formation of fibres. A directed stream of gas deflects the fibres into the wool chamber and deposits them on a collecting organ, which can consist of a perforated conveyor belt or one or more perforated drums.

The fibrillation unit can alternatively consist of a rapidly rotating centrifugal receptacle with a perforated peripheral surface. The melt runs down into the centrifugal receptacle and is thrown out through the holes and converted to fibre. A stream of gas deflects the fibres to the wool chamber and deposits them on the collecting organ.

A thermosetting binder is added to the stream of flibres in the wool chamber so that the fibres shall fasten to each other to form a mat of mineral wool.

The addition of the binder is the cause of a troublesome problem. The binder deposits itself as small sticky drops on the fibres and wads of wool with the consequence that the fibres and wads of wool which touch against the walls of the wool chamber easily fasten to the walls as a result of the adhesive action of the binder. The binder hardens 2~! I _Y;I~I_

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5 5@6 5* S S 0Se According to the present invention, there is provided an apparatus for cleaning the inner surfaces in a wool chamber for manufacture of mineral wool, said wool chamber comprising a space enclosed by side walls, floor and roof, and having an inlet end, said wool chamber including a fiberisation unit in the inlet end from which the fibres formed are deflected with the aid of gas jets towards a receiving conveyor comprising at least one wall of the wool chamber and deposited thereon, in which arrangement the roof and/or walls of the wool chamber consist of double walled construction having a cavity between the double walls, wherein the inner wall(s) of the double walled constructions are perforated and a reduced pressure acting in the cavity between the double walls is 15 arranged to hold a thin, heat-resistant detachable lining against the surface of the perforated inner wall(s) facing the chamber by means of suction.

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The walls of the wool chamber have accordingly been made into a double construction in known fashion and the inner surface of the walls has been perforated. Within said double construction a reduced pressure has been arranged with the aid of which a heat-resistant detachable lining is held fast against the inner wall by suction. When the lining has become coated with so much mineral wool that it is necessary to carry out cleaning, this is done simply by interrupting the reduced pressure in the double walls, after which the lining comes off and can be readily gathered up. New lining can be simply applied in place after the reduced pressure has been re-applied.

The detachable lining is suitably of metal and can be aluminium foil or thin sheet metal. Teflon is also a suitable lining material. The detachable lining can also be a dense heat-resistant cloth which possibly is coated with teflon or aluminium. The lining is suitably cut into pieces which are fitted to the shape of the walls of the wool chamber.

It is then a simple matter to put the lining in place.

The reduced pressure is appropriately achieved by means of a suction fan when the lining is flexible and the pressure reduction does not need to be so great. When the lining is of stiffer material, e.g. thin sheet metal, a vacuum pump is used. Preferably there should be a separate suction fan or vacuum pump respectively for the roof area of the wool chamber and one for each wall.

The pressure reduction in the walls should be considerably greater than that which normally prevails in the wool chamber, which is approx. 50 200 mm water column. The pressure reduction in the walls should therefore be preferably at least 500 mm water column.

WO 88/10242 PCT/F!88/0 0 0 9 4 It is also advantageous to divide the double-skinned roof and wall constructions into smaller sections and furnish them with safety systems which guarantee that the reduced pressure is maintained in the other sections even if the perforated lining is damaged or comes loose in some part of the wall or roof.

The shape and pattern of the perforation can vary. The holes can be circular, oval or rectanglar and the pattern of the holes can be chosen freely. The size of the holes shall not be greater than that used on the receiving conveyor of the wool chamber. Namely if some part of the detachable lining of the walls of the wool chamber is missing, some of the fibres from the stream of fibres will be drawn against the exposed holes and cover them. If the holes were too large the fibres would be sucked through the holes and a continuous leakage of fibres would occur.

A combined hole area amounting to 20 60 of the total area is suitable.

When fibre manufacture is in progress binder-coated fibres are continuously deposited on the lining-covered walls of the wool chamber. When the deposit has reached a certain thickness production is halted and the reduced pressure in the walls of the wool chamber is broken off, whereon the detachable lining immediately comes off and falls down to the bottom of the wool chamber, from-where it can readily be gathered up. The reduced pressure is then reconnected and clean lining sucked onto the walls of the wool chamber, after which production can be resumed. The lining should be changed about as often as the walls of the chamber are scraped clean today, i.e. about once a week. Compared with scraping clean, exchange of the detachable lining is considerably faster and simpler.

In the following the invention is described in greater detail with reference to the accompanying figures which il o o.i flt^

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WO 88/10242 PCT/F188/00095 lustrate two advantageous embodiments of the arrangement according to the invention and in which Figure 1 shows a vertical cross-section of the arrangement according to the invention applied to a wool chamber for the manufacture of glass fibre and Figure 2 shows a vertical cross-section of the arrangement according to the invention applied to a wool chamber for the manufacture of mineral wool.

In the figures the reference number 1 denotes the stream of glass fibres or mineral fibres respectively, the number 2 the collected fibre mat, the number 3 the receiving conveyor on which the mat is formed. The number 4 denotes a suction box beneath the receiving conveyor and the number an outlet for the stream of gas which is sucked out. The outlet is connected to a fan which is not shown. The number 6 denotes the inner perforated wall in the double wall constructions, the number 7 the cavity space in said constructions, the number 8 the detachable lining which is held against the inner wall by suction and the number 9 the unperforated outer wall in the wall construction. The number 10 denotes a spacing piece in the double wall and the number 11 denotes an air oulet to the suction fans.

In the embodiment according to Figure 1 the glass melt is thrown out through the holes in the fibrillation unit and converted to fibres. A first gas stream stretches out the glass fibres 1 and subsequent directed gas streams guide the possibly oscillating fibre streams 1L andI 1R (instantaneously the left and the right) towards the wool chamber and the receiving conveyor 3 on which the fibre mat 2 is formed. The addition of hinder is not shown in the figure.

The vertical walls are constructed as double walls 6, 9 with a cavity 7 between them. The inner walls 6 are periii WO 88/10242 PCT/FI88/00 09 6 forated and a detachable lining material 8 is held against them by suction. Particularly in the lower parts of the wool chamber the outermost layer of the fibre streams comes into contact with the walls of the wool chamber and fastens to the lining 8 on the inner walls. When the deposit on the lining 8 has reached a certain value the detachable lining is replaced in the way described previously. The suction pressure is conducted through the outlet 11 which is connected to suction fans which are not shown.

In the embodiment according to Figure 2 the mineral melt runs down onto a fibrillation unit consisting of rapidly rotating cylinders and strikes the peripheral surface of the first cylinder, from where the melt is thrown onto the peripheral surface of the next cylinder and simultaneously drawn out into fibres. A gas jet defects the fibre stream 1 against the upwards inclined receiving conveyor 3. The reduced pressure in suction box 4 draws the fibre stream towards the receiving conveyor which transports the fibre mat 2 formed to the following stage of production. The roof is of double construction and consists of an outer jacket 9 and a perforated inner surface 6, against which the detachable lining 8 is held fast by suction. The reduced pressure is achieved in the same manner as in the preceding case.

The side walls which are not shown are also of double construction and furnished with a lining in the same manner as in the wool chamber according to Figure 1.

The outlet 11 can be furnished with non-return valves which prevent the ingress of air during momentary disturbances in the vacuum system. The double walls can be divided into sections and furnished with a safety system which guarantees that the reduced pressure is maintained in the other sections even if some part of the detachable lining is damaged or comes off. The spacing piece 10 has been introduced into the double walls to prevent the walls being collapsing as a consequence of the reduced pressure.

.h Ilsl I i I WO 88/10242 PCT/F188/00095 7 The suction fan,not shown, which creates the reduced pressure can be a suction fan or a vacuum pump. The choice of type depends on how great a reduction of pressure is needed in order to overcome the reduced pressure in the wool chamber and to hold the detachable lining in place. The pressure reduction in the wall constructions should be appreciably greater than the pressure reduction in the wool chamber since the latter affects the entire surface, i.e. the entire lining, whereas the pressure reduction in the walls affects only the perforated part, i.e. 20 50 of the surface. As noted earlier the reducticn of pressure in the wool chamber is normally between 50 and 200 mm water column, so that the reduction in pressure in the wall constructions should preferably be at least 500 mm water column. Flexible foil material is suitably held in place by suction fans and stiffer material by vacuum pumps.

Alternatively one can contemplate facilitating cleaning of the wool chamber walls by means of applying an excess pressure in the double wall construction and producing a fluidizing layer adjacent to the inner wall, thus creating a repellent effect on the inner wall and thereby preventing loose fibres from depositing themselves on the inner wall.

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Claims (9)

1. An apparatus for cleaning the inner surfaces in a wool chamber for manufacture of mineral wool, said wool chamber comprising a space enclosed by wide walls, floor and roof, and having an inlet end, said wool chamber including a fiberisation unit in the inlet end from which the fibres formed are deflected with the aid of gas jets towards a receiving conveyor comprising at least one wall of the wool chamber and deposited thereon, in which arrangement the roof and/or walls of the wool chamber .e consist of double walled construction having a cavity between the double walls, wherein the inner wall(s) of the double walled constructions are perforated and a reduced 15 pressure acting in the cavity between the double walls is arranged to hold a thin, heat-resistant detachable lining •against the surface of the perforated inner wall(s) facing the chamber by means of suction.

2. An apparatus according to Claim i, wherein said S* double walled constructions each have their own *oS* pressure-reducing device. ooooo

3. An apparatus according to Claim 1 or 2, wherein said 25 double walled constructions are divided into sections with a safety system which guarantees reduced pressure in the other sections in the event of disturbances in one or more sections.

4. An apparatus according to any one of Claims 1-3, wherein the total area of said perforations in the inner wall(s) constitute altogether 20-60% of the total area of the detachable lining.

5. An apparatus according to Claim 4, wherein the size of said perforations in the inner wall(s) is less than or equal to the size of the holes provided in the perforation on the receiving conveyor. 8 ~-P 1'

6. An apparatus according to any one of the preceding claims, wherein said detachable lining consists of separate pieces which are fitted to the shape of the roof and walls respectively.

7. An apparatus according to any one of the preceding claims, wherein said detachable lining is metal, for example an aluminium foil or thin sheet metal, teflon or a dense heat-resistant cloth.

8. An apparatus according to claim 1, substantially as herein described with reference to the accompanying drawings. S* 5 DATED: 1 November 1991 •PHILLIPS ORMONDE FITZPATRICK Attorneys for: OY PARTEK AB AL.

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