EP1907121B1 - Safety system for a roller mill - Google Patents

Abstract

In order to minimize the loss of production of a crushing plant, particularly a cement crushing plant and optimize on the gear side the availability of the roller mill, according to the invention a replacement gear is provided alongside the operating mill gear. The mill gear and replacement gear are located on at least one base plate and preferably together with a drive motor for the mill gear and a second motor for the replacement gear, as well as with a lubricating system located between the mill gear and the replacement gear, are preassembled on the base plate. The base plate is horizontally adjustably guided on the mill foundation. If the mill gear fails the base plate with the units mounted thereon can be adjusted in such a way that the replacement gear is positioned below the crushing pan in the place of the mill gear.

Description

The invention relates to a safety system for a roller mill according to the preamble of claim 1 known, for example from DE19 702 854 ,

It is known to use Wälzmühlen for grinding a variety of materials. Roller mills have considerable advantages in terms of design and control as well as in terms of energy consumption, environmental behavior and overall economy.

In the cement industry, roller mills are used both for the production of cement raw meal and for clinker milling and coal grinding. If raw material grinding plants are operated in conjunction with rotary kilns and a calcination plant, the kiln exhaust gases from the heat exchanger and clinker cooler process can be used for mill drying and for the pneumatic transport of the ground cement raw material or coal.

As a rule, two-, three- and four-roller mills, which are constructed according to the modular system, are used. An air flow roller mill in modular design according to the LOESCHE system is off EP 0 879 086 B1 known. In Fig. 1 Such a roller mill is shown in sections in a side view and without housing. Grinding rollers 2, each with a rocker arm 21 about a swing lever axis 22 in a Bearing 29 of a stand 20 are pivotally mounted, roll on a driven by a drive shaft 26 via a gear 4 grinding bowl 3. The Wälzmühle according to Fig. 1 has two grinding rollers, of which only one grinding roller 2 is shown. Shown is also a rocker arm unit of a rocker arm cylinder 23 and a hydraulic accumulator or a gas spring 24. The stands 20, which are each associated with a grinding roller 2, are at its lower end in a region of a mill foundation 5, which is usually a concrete foundation, attached to a steel foundation frame 15. The mill gear 4 is anchored via an intermediate plate or a gear base plate 27 in the mill foundation 5 or foundation frame 15.

To ensure the required reliability of a cement plant in a continuous operation of the rotary kiln by a corresponding mill performance, safety concepts are known. An Indian DE 103 43 218 A1 described roller mill safety system provides for a constant availability of at least four grinding rollers by the arrangement of more than four grinding rollers, the grinding rollers are arranged in pairs opposite each other and four grinding rollers provide about 80% of the full mill power in a four-roller operation.

Preferably, six grinding rollers are arranged, and in case of damage to a grinding roller, a rocker arm or suspension member, the roller mill is operated with four rollers after the defective grinding roller and its opposite grinding roller were swung out. The advantage of this safety concept is that the roller mill continue to be operated with damage to the grinding rollers, rocker arm or suspension systems after a brief stop and swing a pair of grinding rollers with four grinding rollers can and the raw meal production and thus the furnace operation does not have to be stopped. The swung-out grinding rollers, rocker arms or suspension systems can be separated or replaced.

A disadvantage, however, is that the roller mill must be put out of action in a gear damage, whereby the subsequent processes are interrupted and in a cement plant, for example, the clinker production is stopped. It is necessary to repair the gearbox and to pull it out from under the mill for this purpose, after removing the electric drive motor including the coupling and disconnecting all connecting piping to a lubrication system.

As an alternative to an immediate on-site repair, a replacement transmission can also be installed, if available. Repair and installation of a replacement gearbox, however, require several days of removal and installation time.

For this reason, the conventional safety concept is preferred by the operators, according to which two parallel roller mills are combined with a rotary kiln for the raw meal processing at high furnace outputs. However, this two-mill variant is associated with correspondingly high investment costs.

The invention has for its object to provide a security system for a rolling mill, particularly for a roller mill in modular construction, which ensures the transmission side with a low capital and installation costs, a high availability of the roller mill. According to the invention the object is achieved by the features of claim 1. Advantageous and advantageous embodiments are contained in the subclaims and in the description of the figures.

A basic idea of the invention can be seen to provide a change concept for the mill gear, which allows a rapid replacement of the mill gear and possibly the drive motor and the lubrication system and keeps the downtime and the resulting production loss extremely low.

According to the gear-side safety system according to the invention for a roller mill, a second gear is provided as a replacement or replacement gear, and the mill gear and the exchange gear is arranged on at least one base plate. The base plate is arranged, preferably in predetermined paths, adjustably on the mill foundation or the foundation frame and arranged on the base plate exchange gear can be damaged by adjusting the base plate in place of the mill gear, i. into the mill area and under the grinding bowl. According to the invention, this requires only an adjustment of the at least one base plate.

In a preferred embodiment variant, the mill gear located in operation and the electric drive motor connected to the mill gear via a torsionally flexible coupling are arranged on a horizontally adjustable base plate and aligned exactly with one another. The units are arranged side by side and on a longitudinal axis of the base plate, and on the motor side facing away from the mill gear, a second mill gear as a Replacement or replacement gear and a connected via a clutch engine further pre-assembled. The required lubrication system for the transmission lubrication is located between the mill gear and the replacement gear and connected via pipes to both gears.

In the event of a defect in the mill gear in operation, the grinding bowl is lifted after loosening fastening screws and supported separately. Subsequently, the entire base plate is longitudinally displaced, such that the exchange gear is positioned under the grinding bowl. After lowering and fixing the grinding bowl, the mill operation can be resumed.

The particular advantage of this transmission safety concept according to the invention is that the defective transmission can be repaired without disturbing the grinding operation or removed for repair. The safety system is suitable for cement plants and other central grinding plants and leads to significant time savings in a gearbox change.

Another advantage of this safety concept is that the loosening and subsequent reconnection of the lubrication lines, the time-consuming alignment of the individual components, gear, clutch, motor to each other, as well as the sequence of the removal and subsequent installation omitted or not respected.

Conveniently, the individual units are arranged side by side on the longitudinal axis of the base plate, and the base plate is designed to be displaceable in the direction of its longitudinal axis.

An alternative safety system provides a common base plate with a pre-assembled mill gear, a replacement gearbox and a common lubrication system, which can be adjusted horizontally. In case of damage of the mill gear in operation, the drive motor arranged outside the base plate is disassembled and mounted on the opposite side after the base plate has been moved to its new position. In this new position, the replacement gear is positioned in the mill center and under the grinding bowl and is connected to the displaced drive motor.

Another alternative provides a transmission-safety system in which the base plate with the aggregates arranged thereon not only horizontally and in the direction of the longitudinal axis of the base plate is displaceable, but can also be rotated about a vertical axis. On a common base plate, the operating mill gear, the lubrication system and the exchange gear are mounted, while the drive motor outside of the adjustable base plate on a separate frame or a console, which allows the alignment of the shaft journals of transmission and motor to each other, is arranged.

In case of a gear damage, the base plate in the opposite direction, relative to the drive motor, linearly displaced from the mill area and outside the mill area by 180 ° about the vertical axis, which may be provided in the lubrication system rotated. Thereafter, the base plate is pushed back in the direction of mill area and drive motor, the exchange gear is now arranged under the grinding bowl in the operating position and can be connected to the drive motor via the clutch.

Conveniently, the base plate is dimensioned such that an arrangement and longitudinal displacement between each two stands of the roller mill is ensured.

It is advantageous that the alternative safety systems can be used on both two-, four- and six-roller arrangements.

Roller mills with an odd number of rolls, e.g. Three- or five-roller mills are the preferred catchment area of the following gearbox variant. Here, a first and second base plate are used. On the first base plate, which is located in the mill area or under the grinding bowl, the mill gear, the drive motor and the clutch are mounted aligned with each other. On the second base plate, the replacement gearbox, the second motor and a clutch are mounted ready for use. The lubrication system can be placed separately next to the mill gear or is also on the respective base plate, in which case two lubrication systems are used.

In the event of a malfunction of the mill gear in operation, the entire unit of the first base plate is withdrawn from the mill area and laterally, i. shifted at right angles to the longitudinal axis of the first base plate in an area designated as a repair area. The second base plate with the exchange gear is defined by a region designated as an application region, e.g. transversely to the longitudinal axis of the second base plate, moved and then passes through a longitudinal displacement in the mill area and under the grinding bowl.

In a variant embodiment, the second base plate can be provided without a motor and the drive motor can be arranged on this second base plate if necessary.

Since this concept provides for a longitudinal displacement only by means of a removal opening formed by two uprights, it can be used, in particular in the case of mills with an odd number of rollers, in which the opposite side is blocked by a mill stand.

It is advantageous that the displacement of the base plate can take place in a manner customary for heavy-load transports.

The use of lifting devices and displacement devices is expedient. If hydraulic press bodies are used as lifting devices, these can be arranged between the base plate and the displacement device.

As a sliding device heavy duty rollers, which are arranged on guideways on both sides of the base plate on the mill foundation and a winch, which acts on the base plate, are used.

It is also possible to perform the longitudinal displacement of the base plates and the rotation by means of a hydraulic sliding film and the like.

The base plate may be formed like a frame and fixed to the mill foundation or the foundation frame.

Fig. 1

eine halbe Seitenansicht einer Wälzmühle in Modul- bauweise, jedoch ohne Gehäuse;

Fig. 2

eine Variante des erfindungsgemäßen Getriebe- Sicherheitssystems vor dem Getriebewechsel;

Fig. 3

das erfindungsgemäße Getriebe-Sicherheitssystem nach dem Getriebewechsel;

Fig. 4

eine Grundplatte des erfindungsgemäßen Getriebe- Sicherheitssystems;

Fig. 5

eine vergrößerte Darstellung des Ausschnittes V in Fig. 4;

Fig. 6

eine zweite Variante eines Getriebe-Sicherheits- systems und

Fig. 7

eine dritte Variante eines Getriebe-Sicherheits- systems.

The invention will be further explained below with reference to a drawing; in this show in a highly schematic representation

Fig. 1

a half side view of a roller mill in modular design, but without housing;

Fig. 2

a variant of the transmission safety system according to the invention before the gearbox change;

Fig. 3

the transmission safety system according to the invention after the gearbox change;

Fig. 4

a base plate of the transmission safety system according to the invention;

Fig. 5

an enlarged view of the section V in Fig. 4 ;

Fig. 6

a second variant of a transmission safety system and

Fig. 7

a third variant of a transmission safety system.

In Fig. 1 is a half-side view of a known roller mill with two grinding rollers, but only a grinding roller 2 and a stator 20 is shown, is shown. The mill gear 4 below the grinding bowl 3 is connected via a Getriebefußplatte 27 with the foundation frame 15 of the mill foundation 5, which is a concrete foundation.

The Fig. 2 to 5 show a first embodiment of the transmission-side safety system according to the invention for a roller mill in modular design.

For identical features, identical reference numerals are used in all figures.

In the Wälzmühle the Fig. 2 and 3 , which show only the components of interest here, is a six-roll mill in modular design. To the mill center with the mill gear 4 are six modular units, shown here by six stands 20 with bearing block 29 for the oscillating lever axis 22 of the grinding roller (not shown), respectively.

The stands 20, the mill gear 4, a drive motor 6 and a lubrication system 7 are on a mill foundation 5, which is a concrete foundation with cast foundation frame (not shown) arranged.

In order to create an efficient change concept for the mill gear 4, with which the production downtime can be kept in an extremely favorable time frame of, for example, less than 24 hours, the mill gear 4 and the drive motor 6 are exactly aligned with each other together on a base plate 10 fixed. The mill gear 4 is connected via a torsionally flexible coupling 9 to the electric drive motor 6, and the mill gear 4 is in the mill area 8, i. positioned centrally and below the grinding bowl, not shown.

The common base plate 10 is adapted to receive further units and horizontally adjustable along its longitudinal axis between two stands 20. In the other units is a second transmission, which is arranged as a replacement gear 14 mirror-symmetrical to the mill gear 4 next to the lubrication system 7. The exchange gear 14 is connected via a torsionally flexible coupling 9 with a second motor 16, which like the exchange gear 14 on the common base plate 10th is mounted. The base plate 10 is supported on the mill foundation 5 and the foundation frame 15, not shown, and displaceable in the longitudinal direction (see double arrow A). This longitudinal displacement takes place on guide tracks 34 for rollers, which in conjunction with the Fig. 5 be explained further.

In case of failure of the mill gear 4, the grinding bowl (not shown) raised after loosening the mounting screws and supported separately. Subsequently, the base plate 10 is mounted with mounted thereon unit of mill gear 4, drive motor 6, lubrication system 7, exchange gear 14 and second motor 16 such that the exchange gear 14 enters the mill area 8 and below the grinding bowl (see Fig. 3 ). After lowering and fixing the grinding bowl, the mill operation can be resumed. The defective mill gear 4 is due to the displacement of the common base plate 10 outside of the mill area and can be removed for repair.

The longitudinal displacement of the base plate 10 takes place in the embodiment of FIGS. 2 to 5 with the help of winches 36 and an attacking on the base plate 10 pull rope 38. The base plate 10 can be moved back into the mill area 8 with the repaired, original mill gear 4 and the drive motor back when the exchange gear 14 in use or the second motor 16 fail.

The 4 and 5 show a arranged on the base plate 10 unit for quick change concept for transmission according to the Fig. 2 and 3 , but without mill stand. The mill gear 4 and the exchange gear 14 are connected via a Gear base plate 27 mounted on the common longitudinally displaceable base plate 10. The drive motor 6 and the second motor 16 of the exchange unit are each connected via a torsionally flexible coupling 9 with the mill gear 4 and the exchange gear 14 aligned exactly to each other. The drive motor 6 and the second motor 16 are mounted for this purpose on a frame 32, which allows the alignment of the shaft journals of transmission and engine to each other.

The longitudinal displacement of the base plate 10 is performed by means of lifting devices 30 and displacement devices 31. Fig. 5 shows a lifting device 30 and shifting devices 31 in detail. As lifting device 30, hydraulic compacts 37 are arranged between the base plate 10 and the displacement device 31. The displacement device 31 comprises Schweriastrollen 35, which are guided on guideways 34, and arranged at a distance of the displacement cable winches 36th

Fig. 6 shows an alternative exchange concept for a mill gear 4. On a base plate 10 are arranged as a preassembled unit a mill gear 4, an exchange gear 14 and between these a lubrication system 7, which is connected via pipes to both transmissions 4, 14. Outside the common base plate 10, a drive motor 6 is connected via a torsionally flexible coupling 9 with the mill gear 4 under exact alignment. If the mill gear 4 which is in operation is damaged, the drive motor 6 is dismantled and the base plate 10 is displaced in such a way that the exchange gear 14 is located in the mill area and below the grinding bowl (not shown). The dismantled drive motor 6 is mounted on the opposite side and connected to the exchange gear 14.

Alternatively, the base plate 10 could also be pulled to the side facing away from the engine (arrow C) from the mill area 8, which is shown highly schematically by the longitudinal axis 25 and rotated by 180 about a vertical axis 12, which may be located for example in the lubrication system 7 and then moved according to arrow D again in the longitudinal direction of the base plate 10 in the mill area 8. Below the grinding bowl in the mill area 8 is then the exchange gear 14 and can be connected to the drive motor 6.

In Fig. 7 is a further alternative for a gear change by means of a horizontally displaceable base plate 10 shown highly schematically. In this concept, the mill gear 4 and the drive motor 6 are arranged together on a first base plate 10 in the mill area 8. The lubrication system 7 is arranged on the side facing away from the motor and outside the base plate 10. In an application area 19, which is arranged parallel to a longitudinal displacement area 28 for the base plate 10, a second base plate 13 is provided ready for use with a mounted thereon exchange gear 14 and second motor 16.

In case of failure of the mill gear 4, the base plate 10 is displaced in the direction of the longitudinal axis 11 from the mill area 8 in the longitudinal displacement portion 28 as indicated by arrow E and passes through a transverse displacement according to arrow F in a repair area 18. This repair area 18 is parallel to the application area 19 in this embodiment and disposed on the opposite side of the longitudinal sliding portion 28. The second base plate 13 is now moved transversely to its longitudinal axis 33, ie according to arrow G, in the longitudinal displacement region 28 and then pulled or pushed in the longitudinal direction according to arrow H in the mill area 8.

Alternatively, in each case a lubrication system 7 may be mounted on the first base plate 10 and on the second base plate 13. Since the degradation of the connecting pipes to the lubrication system can be omitted, a further time savings is achieved.

In Fig. 7 For example, a four-roll mill with four mill stands 20 is shown. However, the transmission change variant is particularly suitable for mills with an odd number of rollers, in which the motor opposite side is blocked by a mill stand, suitable.

Claims (20)

1. Safety system for a roller mill
   with crushing rollers (2) rolling on a rotary crushing pan (3),
   with a mill gear (4), which is positioned below the crushing pan (3) and supported on a mill foundation (5) and
   with a drive motor (6) and a lubricating system (7) for the mill gear (4), characterized in that
   for ensuring the permanent availability of the roller mill a replacement gear (14) is provided,
   the mill gear (4) and the replacement gear (14) are placed on at least one base pilate (10, 13),
   the base plate (10, 13) is horizontally adjustable on the mill foundation (5) and in the case of a failure to the mill gear (4), by adjusting the base plate (10, 13), the replacement gear (14) can be positioned below the crushing pan (3) in place of the mill gear (4).
2. Safety system according to claim 1,
   characterized in that
   the base plate (10) is constructed for a joint arrangement of the mill gear (4) and the drive motor (6) connected by means of a coupling (9) to the mill gear (4), the lubricating system (7), the replacement gear (14) and a second motor (16), the lubricating system (7) being positioned between the mill gear (4) and the replacement gear (14) and the in each case externally located drive motor (2) or second motor (16).
3. Safety system according to claim 1 or 2,
   characterized in that
   the base plate (10) is constructed so as to be displaceable in the direction of its longitudinal axis (11).
4. Safety system according to one of the preceding claims,
   characterized in that
   the base plate (10) is displaceable in a longitudinal displacement area (28) between two adjacent mill standards (20) of a roller mill in a modular construction.
5. Safety system according to one of the preceding claims,
   characterized in that
   the mill gear (4) and the drive motor (6), as well as the replacement gear (14) and the second motor (17) are precisely mutually oriented.
6. Safety system according to one of the preceding claims,
   characterized in that
   the mill gear (4) and the drive motor (6) and/or the replacement gear (14) and the second motor (16) are interconnected by means of a torsionally elastic coupling (9).
7. Safety system according to one of the preceding claims,
   characterized in that
   the lubricating system (7) between the mill gear (4) and the replacement gear (14) is connected by means of pipes to the mill gear (4) and the replacement gear (14).
8. Safety system according to one of the claims 1 and 3 to 7,
   characterized in that
   the mill gear (4), lubricating system (7) and replacement gear (14) are jointly placed on the base plate (10) and the drive motor (6) is connected to the mill gear (4) and that in the case of a failure to the mill gear (4) the base plate (10) is longitudinally displaceable in the direction of the drive motor (6) for positioning the replacement gear (14) in the operating position below the crushing pan (3) and the drive motor (6) is positionable alongside and connectable to the replacement gear (14).
9. Safety system according to one of the claims 1 and 3 to 7,
   characterized in that
   the mill gear (4), lubricating system (7) and replacement gear (14) are jointly placed on a base plate (10) adjustably placed on the mill foundation (5) in the direction of its longitudinal axis (11) and about a vertical axis (12).
10. Safety system according to claim 9,
    characterized in that
    after failure to mill gear (4), the base plate (10) is displaceable towards the motor-remote side from the mill area (8) and outside said mill area (8) can be rotated by 180° about the vertical axis (12) and moved back in longitudinal direction into the mill area (8) and that the replacement gear (14) is placed in the operating position below the crushing pan (3) and can be connected to the drive motor (6) located outside the base plate (10).
11. Safety system according to claim 1,
    characterized in that
    the mill gear (4) and drive motor (6) are jointly and in mutually oriented manner placed on the first base plate (10) and a replacement gear (14) and a second motor (16) are jointly placed in mutually oriented manner on a second base plate (13) and
    that the first and second base plates (10, 13) are guided in horizontally adjustable manner on the mill foundation (5) and in the case of a failure to mill gear (4), following the adjustment of the first base plate (10), the second base plate (13) with the replacement gear (14) can be positioned in the operating position below the crushing pan (3).
12. Safety system according to claim 11,
    characterized in that
    the lubricating system (7) is located outside the first and second base plates (10, 13) on the motor-remote side of the mill gear (4) or replacement gear (14) positioned in the operating position.
13. Safety system according to claim 11,
    characterized in that
    in each case a lubricating system (7) is placed on the first and second base plates (10, 13) on the motor-remote side of the mill gear (4) or replacement gear (14).
14. Safety system according to one of the claims 11 to 13,
    characterized in that
    in the case of a failure to mill gear (4), the first base plate (10) is displaceable in the direction of its longitudinal axis (11) out of the mill area (8) and into a repair area (18) and
    that the second base plate (13), positioned in ready-to-use manner in a use area (19), is displaceable into the mill area (8) and into the operating position of the replacement gear (14) below the crushing pan (3).
15. Safety system according to claim 14,
    characterized in that
    the first base plate (10) is displaceable in the direction of its longitudinal axis (11) in a longitudinal displacement area (28) from the mill area (8) and transversely to its longitudinal axis (11) into the repair area (18) and that the second base plate (31) is displaceable from the use area (19), which is axially parallel to the repair area (18) and to the longitudinal displacement area (28),
    transversely to its longitudinal axis (33) into the longitudinal displacement area (28) and then in the direction of its longitudinal axis (33) into the mill area (8) and the operating position of the replacement gear (14) below the crushing pan (3).
16. Safety system according to one of the preceding claims,
    characterized in that
    lifting devices (30) and displacement devices (31) are provided for the displacement of the base plate (10, 13).
17. Safety system according to one of the preceding claims,
    characterized in that,
    as lifting devices (30) hydraulic press bodies (37) are provided between the base plate (10, 13) and the displacement device (31).
18. Safety system according to claim 16 or 17,
    characterized in that
    the displacement device (31) has heavy duty rolls (35) guided on guideways (34) and a cable winch (36) acting on the base plate (10, 13).
19. Safety system according to one the preceding claims,
    characterized in that
    the base plate (10, 13) is adjustable by means of a hydraulic sliding film, floating pads and the like.
20. Safety system according to one of the preceding claims,
    characterized in that
    the base plate (10, 13) has a frame-like construction and can be fixed, at least in the operating position, to the mill foundation (5) or foundation frame (15).

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