Grating bar for step grating

Abstract

A grate bar front section (10) for mounting on a grate bar back section (20) in order to form a grate bar (1) for example for a waste incineration plant, wherein the grate bar front section (10) has a refractory mineral material and a top (14), a bottom (12), a front (16), two narrow sides, and a back (18) as well as a grate bar longitudinal axis (2) extending parallel to the top (14) through the front (16) and the back (18), characterized in that - a recess (70) extends from the underside (12) towards the top (14), - the recess (70) has at least one contact surface (71) for introducing a force acting in the direction of the rear (18) and / or the front (16) into the grate bar front section (10), and - at least one channel (32) with a channel longitudinal axis (33) connects the rear (18) and / or the front (16) and / or at least one side surface 15 with the recess (70), wherein the channel (32) can accommodate a bolt (30) or other connecting element for fastening the front section (10) to the rear section (20) and / or to a front plate (160).

Description

Technical field

[0001] The invention relates to a grate bar front section and a matching grate bar back section, as well as a grate bar with the grate bar front section and / or the grate bar back section. State of the art

[0002] Waste incineration is a collective term for waste disposal processes in which waste materials are burned. Waste incineration reduces the original volume of the waste. One waste incineration method is grate firing. This can involve the use of stepped grates and / or moving grates. The grate consists of several rows of grate bars, usually braced laterally. The different rows of the grate overlap, with the front section of each grate bar overlapping the rear section of the grate bars positioned ahead in the conveying direction. This creates a shallow stepped structure along which the waste to be incinerated is pushed forward by an oscillating motion. Depending on their position within the moving grate, the grate sections can be air-cooled and / or water-cooled. Lateral division into two or more grate lanes is also possible.

[0003] EP 3 048 369 B1 discloses a grate bar for a moving grate used in waste incineration. The grate bar is manufactured in one piece from a ceramic composite material. For this purpose, a ceramic base material is cast into a casing with a base and side walls made of sheet metal and a perforated support structure. The grate bar has a front section for receiving the material to be incinerated and a rear section designed for attachment to a crossbeam.

[0004] Utility model DE 75 21 218 U discloses a grate plate with a base plate onto the rear end of which a wear bar 5 is pushed. The wear bar 5 engages with its front end in a gap extending longitudinally in the base plate and engages with its rear end the rear end of the base plate.

[0005] German patent application DE 29 30 406 A1 proposes a stepped grate for a clinker cooler, in which one-piece grate plates are mounted side by side in rows on crossbeams. To fasten the grate plates, they are tensioned from below to the crossbeam by means of a tie bolt. For this purpose, each tie bolt has an angled free leg at its upper end, which engages in a complementary hook-like recess on the underside of the respective grate plate.

[0006] DE 10 2004 034 322 A1 discloses a two-part grate bar with a flow channel. The channel has a first funnel-shaped, downward-opening end and is then guided first along the inside of the top surface and then along the inside of the longitudinal side, before leading downwards into an opening so that appropriately directed cooling air strikes and flows onto the top surface of an adjacent grate plate.

[0007] DE 197 14 573 C1 discloses a combustion grate for burning problem waste in thermal combustion plants, which is made of a high-temperature, abrasion- and corrosion-resistant ceramic material. Description of the invention

[0008] The invention is based on the objective of developing a lightweight, inexpensive grate bar that promotes processes on the grate and can withstand high thermal and mechanical stresses, such as those that occur, for example, in waste incineration reactors and cement clinker coolers.

[0009] This problem is solved by a grate bar front section according to claim 1 and a preferably complementary grate bar rear section according to claim 11. These two sections can, for example, be joined together to form a grate bar according to claims 15ff. For example, the grate bar can be designed for and used as part of a waste incineration grate or a clinker cooler grate. Further advantageous embodiments of the invention are specified in the dependent claims.

[0010] The front section of the grating bar, hereinafter referred to as the "front section", can be mounted to a rear section of the grating bar, hereinafter referred to as the "rear section", for example, as described in detail below. The front section can then be attached to a supporting structure, such as a crossbeam, in the usual manner via the rear section. Alternatively or optionally, the front section can be attached to existing rear sections or directly to at least one supporting structure, such as a crossbeam, of a grating.

[0011] The front section comprises a refractory mineral material. For example, the front section can be made of or incorporate refractory or highly refractory concrete, preferably ceramic. These materials make the front section insensitive to thermal, mechanical, and chemical influences such as heat, abrasion, or corrosion.

[0012] For example, the front section can consist at least substantially (i.e., more than 30%, preferably more than 50%, preferably more than 75%, more than 85%, or more than 90%) of the refractory mineral material. Hereinafter, the term "ceramic" is used as a pars pro toto for a refractory mineral material. The ceramic may be reinforced, for example, with steel fibers or other fibers, and the front section is preferably monolithic. Alternatively, only the uppermost centimeters of the top surface of the front section may consist of ceramic.

[0013] The front section has a top, a bottom, a front, two narrow sides, a back, and a longitudinal axis of the grate bar extending parallel to the top through the front and back. The designations of the sides refer to the conveying direction of the grate, i.e., the installed position of the grate bar in the finished grate. In the installed state, the longitudinal axis of the grate bar preferably extends at least approximately parallel to the conveying direction (i.e., it forms an angle of ±20°, preferably ±10°, particularly preferably ±2.5°, or is parallel to the conveying direction). The top can hold the material to be processed, be it material to be incinerated (such as waste or wood chips) or cement clinker (or simply clinker) to be cooled. For simplicity, the space above the surface is therefore called the reactor, even though chemical processes do not necessarily take place there.For example, the material to be processed can be transported towards the front by an oscillating movement of the grate bars on the top side. The top side can be in direct contact with the material being processed and can be exposed to the highest thermal and chemical stresses. The underside is the side of the front section facing away from the top side. The top and bottom sides are connected by the front, the back, and the two narrow sides. As usual, the front side faces in the direction of conveying and is opposite the back. The two narrow sides each connect the front to the back. When assembled, the narrow sides of laterally adjacent front sections typically rest against each other. Here, "adjacent" refers to the front sections of a grate row, with the grate rows extending perpendicular to the conveying direction.An (imaginary) longitudinal axis of the grate bar runs through the front and back of the front section. An (imaginary) vertical axis of the grate bar runs orthogonal to the longitudinal axis of the grate bar and orthogonal to the at least approximately flat top surface. An (imaginary) transverse axis of the grate bar then extends, as usual, orthogonal to the other two axes through the narrow sides and, in the installed state, corresponds to the longitudinal direction of a row of grate bars and the transverse direction of the grate.

[0014] In summary, the front edge defines the front section in the conveying direction, shares an edge with both the top and bottom surfaces, and is preferably flat, although it can also have other geometries. The back edge lies on the side of the front section facing away from the front edge and, like the front edge, shares an edge with both the top and bottom surfaces. The back edge can serve as a contact surface for the rear section and / or as a support structure for the grate.

[0015] The narrow sides each share an edge with the front and back, as well as the top and bottom. The narrow sides preferably extend at least approximately parallel (i.e., ±20°, preferably ±10°, particularly preferably ±2.5° or parallel) to the longitudinal axis of the grate bar.

[0016] Starting from the underside of the front section, at least one recess can extend from an opening in the underside towards the top. The recess does not necessarily end in an opening in the top, but preferably below the top. In this sense, the recess can preferably be a blind hole. The recess preferably has at least one contact surface on the boundary of the recess facing the rear or front side. This contact surface can then transmit a force acting towards the rear or front side into the front section, for example, by positive locking and / or frictional locking. Preferably, the contact surface is convex or flat. This allows compressive forces to be introduced into the ceramic of the front section in a material-friendly manner via positive locking or frictional locking. This increases its service life.

[0017] Starting from the rear and / or the front, a channel can connect the rear or front to the recess. The channel preferably has a longitudinal axis. The channel can, for example, have a cylindrical, particularly circular-cylindrical, contour, i.e., be bounded by a corresponding lateral surface. The channel can preferably taper from the rear and / or the front towards the recess, for example, by tapering continuously. The channel can also be at least partially open to the underside.

[0018] The channel can, for example as detailed below, accommodate a bolt or other connecting element for fastening, preferably clamping, the front section to a rear section. The recess provides a support surface for clamping the connecting element with minimal contact area and also offers access to the connecting element and / or the channel. The channel, together with the recess, therefore allows the front section to be preferably detachably connected to a rear section and / or a front panel. The rear section, which is subject to only minimal wear, can thus be reused, for example, if the corresponding front section is worn or otherwise damaged and needs to be replaced.Furthermore, the front section, the optional rear section, and / or the optional front panel can be manufactured from different materials, making it possible to adapt the front section and the optional rear section cost-effectively to their respective tasks. The same applies accordingly to an optional front panel.

[0019] Here, the term "bolt" is used as a pars pro toto for a connecting element. The term "bolt" could therefore simply be replaced with the term "connecting element," which specifically excludes the typical connecting bolt, e.g., a threaded bolt.

[0020] The ceramic material makes the front section corrosion-resistant and wear-resistant. Ceramic also has a high permissible operating temperature. Thanks to the ceramic, the front section remains dimensionally stable even under high temperature loads and also exhibits a low specific gravity. The disadvantages of the ceramic material are its relatively low tensile strength and brittle behavior. Therefore, the tensile stress exerted on the grate bar must be minimized. In contrast to its low tensile strength, ceramic and the other preferred refractory materials exhibit high compressive strength at high temperatures. With the described bolt fastening, the ceramic of the front section is subjected to compressive stress only, at least essentially, during fastening.

[0021] The preferred tapering of the channel facilitates the demolding of the front section from a mold, as the front section can be easily released from the mold by pivoting and / or rotating movements, minimizing frictional forces.

[0022] Another advantage of the optional channel narrowing is the ease of subsequent assembly and disassembly from a complementary back section or front panel. For example, a bolt can be more easily inserted into the channel during assembly. Furthermore, a bolt that may be stuck can be quickly and easily released during disassembly with a simple pivoting motion. The risk of the bolt becoming stuck to the channel edge is significantly reduced, if not eliminated entirely.

[0023] Preferably, at least one gas line extends from the rear and / or bottom towards the top and / or front and terminates there. The number of gas lines can vary as required (i.e., preferably at least one gas line, more preferably two, three, or more). In other words, the at least one gas line connects at least one inlet in the rear and / or front to at least one outlet in the top and / or front. The gas line can be used to cool the front section, and a process gas (hereinafter referred to as "gas") that heats up as it flows through it can also be conveyed to the top of the front section. The gas can be, for example, air or another gas or gas mixture that promotes combustion, such as preheated primary air for waste incineration or other applications.When used in a cement clinker cooler, the gas can be a cooling gas for cement clinker.

[0024] Preferably, at least one section of the at least one gas line is located above a plane that is parallel to the longitudinal axis and transverse axis of the grate bar and also above the channel. In the assembled state, the gas line is then positioned above the bolt for securing the rear section. Gas flowing through the gas line therefore cools the area of ​​the front section located above the bolt (or more generally, the connecting element), thus reducing the thermal stress on the bolt. Consequently, the service life of the bolt is increased, and it can also be dimensioned with smaller safety margins.

[0025] The gas line thus enables the transport of gas located below the front section to the top of the front section. For example, in a waste incineration plant, primary air can flow from the underside of the grate to the top via the gas line. This primary air heats up in the process, i.e., it absorbs heat from the front section. As a result, the gas reaches the top of the front section at a higher temperature, and less energy is required to heat the primary and / or secondary air.

[0026] The gas pipeline can have a circular cross-section, but the cross-section can also be oval, e.g. elliptical, or polygonal.

[0027] At least one section of at least one insulating body can preferably be arranged between the channel and the top surface and / or more preferably between the recess and the top surface. The number of insulating bodies can vary (i.e., preferably one insulating body, more preferably two, three, or more insulating bodies). The insulating body is made of a material with a lower thermal conductivity than the surrounding ceramic and can be, for example, a rod-shaped body. Such a body can be easily placed in a mold and thus easily inserted into the front section. Mineral wool and / or air, for example, can be chosen as the insulating medium.

[0028] The insulating body reduces heat input into the section below and thus acts as a thermal barrier. This reduces the thermal stress exerted on a bolt located in the channel.

[0029] Provided that at least one gas line as described above is provided, the at least one insulating element can preferably be arranged between the gas line and the channel and / or the recess. This does not reduce the heating of the gas flowing through the gas line and further reduces the heat input into the channel area.

[0030] Particularly when the insulating body is rod-shaped, its longitudinal axis can extend at least approximately (preferably ±10°, more preferably ±2.5° or exactly) in the direction of the grate bar's longitudinal axis and / or the channel's longitudinal axis. In this case, the insulating body can, for example, be arranged above the channel, thus protecting the channel and the optional bolt particularly efficiently from the heat on the top side. Alternatively or additionally, the insulating body or another insulating body is oriented at least approximately orthogonally (i.e., ±20°, preferably ±10°, more preferably ±2.5° or orthogonally) with respect to the grate bar's longitudinal axis. This variant is particularly easy to manufacture, and good thermal protection of the channel and the bolt can be achieved by arranging a plurality of insulating bodies side by side.

[0031] The insulating body can have a circular cross-section, but the cross-section can also be oval, e.g., elliptical, or polygonal. The insulating bodies can be arranged tangentially, overlapping, or preferably side by side, e.g., spaced apart from each other and / or at least approximately parallel to each other (within ±10°, preferably ±5°, particularly preferably ±2.5° or less).

[0032] Preferably, at least one gas passage extends from an inlet on the underside towards the top and terminates in an outlet on the top. The number of gas passages can vary as required (i.e., preferably one gas passage, more preferably two, three, or more). The at least one gas passage allows gas located below the front section to be transported to the top of the front section. The gas can, for example, be a process gas for processes taking place on the top of the grate, such as air or another gas or gas mixture that promotes combustion. For example, in a waste incineration plant, primary or secondary air can flow from the underside of the grate to the top via the gas passage.The gas passage allows for a uniform input of process gas into the reactor or cooling chamber located above the front section, thus the processes in the reactor run more uniformly and it is operated more economically.

[0033] The gas passage can be tilted towards the front relative to the inlet. For example, the gas passage can have a longitudinal axis tilted in the direction of flow, i.e., towards the front, forming an acute angle with the top. This promotes more uniform combustion on the grate surface. More generally, the process gas is supplied to the processes in the reactor (combustion, cooling, etc.) in a particularly uniform manner.

[0034] Preferably, the gas passage is curved towards the front, at least in a region adjacent to the top surface. If a tangent is drawn to the underside of the gas passage at a point of contact in the region adjacent to the top surface, this tangent forms an acute angle with the top surface. As the distance of the tangent's point of contact from the outlet decreases, the value of the angle formed by the tangent and the top surface preferably decreases, and particularly preferably decreases continuously. In particular, the underside of the gas passage can transition continuously into the top surface at the outlet. By tilting and / or curving the gas passage, the gas can flow out in the direction of flow and adhere to the surface in the direction of flow. All these measures therefore further enhance the homogenization of the processes in the reactor.

[0035] At least one optional gas channel can extend from an inlet in the recess towards the top and / or front side and terminate, for example, in at least one outlet in the top and / or front side. At least part of the inlet of this gas channel can be located along the longitudinal axis of the channel. This gas channel can accommodate a cooling fluid (e.g., a process gas) that flows over and cools the surface of a bolt (or other connecting element) that, after assembly, has a back section in the channel. For example, the bolt can be a hollow bolt with the cooling fluid flowing through its axial recess. Additionally or alternatively, at least part of a lateral surface of a connecting element can be exposed to the cooling fluid. The cooling fluid, e.g.,A cooling gas then flows from the underside of the grate bar through and / or over the bolt (as a representative of a connecting element) and optionally via the gas channel, for example, to the top of the front section, thus cooling the bolt particularly effectively. To achieve a continuous gas flow through a hollow bolt, the opening of the recess on the underside can be at least partially closed after assembly. A reduction in the diameter of the opening can be achieved, for example, by using a plug with a smaller diameter than that of the recess opening. If the opening is omitted from the plug, the opening is completely closed.

[0036] The gas passages can, for example, have struts that support the stability of the front section but do not impede the gas flow, or only to a negligible extent. These struts can extend, for example, from the underside to the top.

[0037] The upper surface of the front section can have a greater longitudinal extent than the lower surface. Due to this difference in length, the rear surface has an overhang. The rear surface can, for example, form an at least approximately right angle (within ±25°, preferably ±10°, particularly preferably ±2.5° or better) with the lower surface. Alternatively or additionally, the rear surface can connect tangentially to the upper surface. The rear surface can connect the upper surface to the lower surface in a stepped or curved manner. Preferably, the rear surface is continuously curved. Consequently, the curvature can vary.

[0038] When assembled, the overhang can serve as a thermal and / or chemical shield for the back section. The back section can therefore be made of easily workable, less temperature-resistant materials such as sheet steel. At least one section of the overhang can be located above the back section, thus protecting it from thermal and chemical stresses emanating from above.

[0039] The grate bar back section, i.e., the "back section" for short, can be mounted to a front section, for example, as described in detail below. The back section can be made of metal. The back section preferably has a central section, which is preferably arranged between a first side element and a second side element. However, it can also be composed of more or fewer individual components. The central section can, for example, be an angle profile with a first leg and a second leg. Preferably, the first leg and the second leg are aligned at least approximately orthogonally (i.e., 90° ± 20°, preferably 90° ± 10°, particularly preferably 90° ± 2.5° or orthogonally (90°)) to each other. The common edges of the two legs preferably run parallel to the transverse axis of the grate bar (when properly assembled). The common edges of the two legs each terminate on one side of the two longitudinal sides of the legs.Each leg preferably has at least one through-hole and / or preferably at least one through-opening (i.e., one through-opening, preferably two, three or more through-openings). One of the two side elements is attached to each of the two longitudinal sides of the central part. The narrow sides correspond to the longitudinal sides of the legs.

[0040] The side elements can be easily cut or stamped from a sheet of steel, for example, and are therefore, like the central section, very inexpensive to manufacture. Reinforcements can be added by bending. The expensive steel casting technique otherwise required for grate bars can be avoided. Alternatively, the rear section can also be made as a casting.

[0041] The contour of the side elements is preferably adapted to the crossbeams of a grating substructure, so that the grating bars with their back sections can simply be hooked into the crossbeams. The side elements can preferably each have at least one cutout into which a crossbeam engages from below when assembled.

[0042] The side elements can be attached to the middle part, for example, by gluing, clamping, screwing or preferably by welding.

[0043] The central section of the grate bar back section can have a third leg. The third leg can, for example, share an edge with the second leg. For the sake of simplicity, it is assumed that the first leg is located between the second and third legs; that is, the first leg is the central leg, which preferably has the aforementioned through-hole.

[0044] The third leg is preferably aligned at least approximately parallel (i.e. ±20°, preferably ±10°, particularly preferably ±2.5° or parallel) to the second leg; both together with the first form at least approximately a Z-profile in this sense, i.e. their free ends point away from each other.

[0045] The front section can be connected to the rear section to form a grate bar. A detachable connection is particularly preferred, as this allows the less stressed rear section to be easily reused. As mentioned earlier, the rear section is optional; the front section can also be attached directly to a supporting structure. The connecting element described above can be used for this purpose.

[0046] The middle section of the rear section can at least partially abut the rear of the front section, preferably over its entire surface. At least the first leg (i.e., the first, second, and third legs, preferably the first leg, and particularly preferably the first and / or third leg) can abut the rear. For example, the middle section can abut the rear at at least three different points (preferably over its entire surface). The bearing surfaces of the legs can form a support. The underside of the front section can rest on the third leg.

[0047] One leg can be fastened, preferably clamped, to the rear side with a bolt that passes through the through-hole and the channel. This joins the front and rear sections together to form a grate bar. The bolt can be a threaded bolt, either with a threaded stud (partially threaded bolt) or a full thread. In this sense, the bolt can also be a screw. The bolt can be inserted into the through-hole of the central section located at the rear. The bolt can be received by the channel and terminate in the recess. Again, the term "bolt" stands as a pars pro toto for a connecting element.

[0048] The bolt can be connected to a pressure plate resting against the mounting surface within the recess, for example, by clamping. The bolt and pressure plate can be permanently connected, for example, by a material bond or compression fitting (as an example of a friction-fit connection). Preferably, the bolt and pressure plate are positively and detachably connected. The pressure plate can be, for example, a nut with or without a washer, or a plate with a connecting element designed for connection. The fastening can be achieved, for example, by a bayonet fitting, a barbed connector, or a threaded connection.

[0049] The bolt can be solid or hollow. It can have a through-channel extending along its axis, with a proximal inlet and a distal outlet. The distal outlet can terminate at the opening of a gas channel connecting the recess to the upper surface. The terms proximal and distal refer to the bolt's position relative to the through-hole of the first leg and the rear of the front section, respectively. The proximal end is therefore located at the through-hole of the first leg and the rear of the front section. The distal end refers to the end furthest from this point; in other words, the portion of the bolt that terminates in the recess.

[0050] The hollow bolt has the advantage that a gas flowing through it can cool the bolt. This further reduces the thermal stress acting on the bolt and increases its service life.

[0051] The hollow bolt and its distal outlet in the area of ​​the gas channel inlet, as already described in relation to the gas line and the gas passage, enable the transport of gas located below the front section to the top of the front section. For example, in a waste incineration plant, primary or secondary air can flow from the underside of the grate to the top via the gas channel. This primary or secondary air heats up in the process, i.e., it absorbs heat from the front section.

[0052] The tangents mentioned are of course imaginary tangents that extend orthogonally to the cross axis of the grid bar or a parallel to the cross axis of the grid bar. Description of the drawings

[0053] The invention is described below by way of example, without limiting the general concept of the invention, with reference to the drawings. Fig. Figure 1 shows an embodiment of a grate bar in the assembled state. Fig. 2 shows a longitudinal section of the grate bar. Fig. 1. Fig. Figure 3 shows a top view of another grate bar. Fig. Figure 4 shows the underside of the grate bar. Fig. 3. Fig. Figure 5 shows a longitudinal section of a detail of the grate bar according to the Fig. 3 and Fig. 4. Fig. Figure 6 shows a simplified schematic of the rear end of another variant of a grate bar. Fig. Figure 7 shows a view of a rear section or another front section of the grille bar. Fig. Figure 8 shows a perspective partial section of the rostrum front section. Fig. 7 with a grate bar back section. Fig. Figure 9 shows a simplified schematic of the rear end of another grate bar. Fig. Figure 10 shows an exploded view of the grate bar after Fig. 9. Fig. Figure 11 shows a simplified schematic of the rear end of yet another grate bar. Fig. Figure 12 shows an exploded view of the grate bar after Fig. 11.

[0054] Fig. Figure 1 shows an embodiment of a grate bar 1 with a front section 10 and a rear section 20. The front section 10 and the rear section 20 are detachably connected by a connecting element 30, which is shown here by way of example as a bolt 30.

[0055] The front section 10 has a front 16, a back 18, a top 14, and a bottom 12. The bottom 12 has an optional shoulder 13. The top 14 of the front section 10 has, by way of example, an optional slotted outlet 69 and three optional circular outlets 64, 65, which are shown by reference to Fig. Section 2 will be explained in more detail. The number of outlets 64, 65, 69 is merely exemplary, i.e., preferably at least one outlet. The outlets can also be omitted.

[0056] The upper surface 14 preferably has a greater longitudinal extent along the grid bar longitudinal axis 2 than the lower surface 12, as shown, whereby the rear surface 18 has an overhang that covers part of the upper side of the rear section 20.

[0057] The rear section 20 preferably comprises a central section 22, a first side element 24, and a second side element 26, which can be manufactured cost-effectively from sheet steel, for example. Alternatively, the rear section 20 can also be manufactured as a single piece or consist of a different number of individual components.

[0058] In Fig. 2 is a longitudinal section of the in Fig. The grate bar described in Figure 1 is shown. The grate bar 1 has a front section 10 and a rear section 20. The front section 10 has a top 14, a bottom 12, a front 16 and a back 18. The front section 10 extends along a grate bar longitudinal axis 2.

[0059] The underside 12 can have a shoulder 13 in a section adjacent to the front side 16. In the area of ​​the front side 16, a clamping device 50 can penetrate the front section 10 completely or partially in the transverse direction. Accordingly, the front section 10 preferably has at least one transverse hole in its front third for receiving at least one clamping device 50. The transverse hole can be designed as a through hole or as a blind hole. The optional clamping device 50 can clamp the grate bar 1 to other, adjacent, grate bars so that a grate row can be formed.

[0060] The upper surface 14 can have a greater longitudinal extent along the longitudinal axis 2 of the grate bar than the lower surface 12. This optional difference in the longitudinal extent of the upper surface 14 and the lower surface 12 allows the rear surface 18 to optionally limit a downward overhang. Preferably, the rear surface 18 can have a flat surface that shares an edge with the upper surface 14. Adjoining this flat surface is a preferably curved second surface of the rear surface 18, which connects the first surface to the lower surface 12.

[0061] The underside 12 can have an opening. A recess 70 extends from the opening towards the top side 14. The recess 70 is shown here as an example of a blind hole and preferably has a bearing surface 71 that limits the recess towards the rear.

[0062] Starting from an opening in the rear side 18, an optional channel 32 extends into the recess 70 along a longitudinal channel axis 33. The channel 32 can preferably taper from the rear side 18 towards the recess 70.

[0063] The front section 10 can have at least one optional gas line 60, at least one optional gas channel 61, and / or at least one optional gas passage 68. Each of the gas line 60, the gas channel 61, and the gas passage 68 enables the transport of gas (or another fluid) located below the front section 10 to the upper surface 14 of the front section 10. Assuming a corresponding pressure gradient, the fluid flows obliquely towards the surface 14 due to the gas line 60, gas channel 61, and gas passage 68 being inclined towards the front 16, causing the flow to adhere to the upper surface 14 in the direction of the front 16.

[0064] The optional at least one gas passage 68 extends from an inlet 67 in the underside 12 to an outlet 69 in the top side 14, wherein the inlet 67 may have a larger diameter than the gas passage 68, thereby increasing the flow velocity in the gas passage 68 towards its outlet, which prevents the passage of material located on the top side 14 and at least prevents the gas passage 68 from becoming blocked by material penetrating from above.

[0065] The gas passage 68 is preferably curved towards the front face 16, at least in a region adjacent to the upper surface 14, as shown. In an alternative embodiment, the gas passage can also be straight. A tangent 80 can be applied to the lower side of the gas passage 68. This tangent 80 forms an acute angle 82 with the upper surface 14. As the distance between the point of application of the tangent 80 and the outlet 69 decreases, the value of the acute angle 82 formed by the tangent 80 and the upper surface 14 decreases continuously, and the gas passage 68 transitions continuously into the upper surface 14 at the outlet 69, causing the flow to adhere particularly effectively to the upper surface 14. The outlet 69 is shown here as an example of a slot, wherein the longitudinal direction of the slot preferably runs at least approximately parallel (within ±10°, preferably ±5°, 2.5° or better) to the grate bar transverse axis 4.

[0066] The at least one optional gas channel 61 extends from an inlet 63 in the recess 70 to an outlet 65 in the upper surface 14, wherein the inlet 63 may preferably have a larger diameter than the gas channel 61. The outlet 65 has, by way of example, a circular cross-section.

[0067] A gas line 60 extends from an inlet 62 in the rear 18 to an outlet 64 in the top 14. A second, optional gas line, whose outlet 64 also opens in the top 14, is concealed by the front section 10. The gas lines 60 are located above a plane that is parallel to the longitudinal axis 2 and the transverse axis 4 of the grate bars and also above the channel 32. The outlets 64 have, by way of example, a circular cross-section (other cross-sections are also possible, in particular oval or polygonal cross-sections).

[0068] Eight optional insulating bodies 66 are arranged parallel to each other, preferably at least approximately orthogonally to the longitudinal axis 2 of the grate bar (within 3 ± 10°, preferably ± 5°, 2.5° or better). In the example shown, the insulating bodies 66 are arranged above the channel 32 and the recess 70, thus protecting the bolt 30 and the pressure plate 40 in the channel 32 and the recess 70, respectively. The number of insulating bodies 66 is also to be understood as exemplary; that is, they can be omitted. Preferably, however, at least one insulating body 66 is implemented, which is preferably arranged above the channel 32; that is, preferably the at least one insulating body is arranged as a heat shield above the channel 32.

[0069] The longitudinal section of the rear section 20 shows the central section 22 and a first side element 24. The central section 22 has, by way of example, a first leg 220, a second leg 221, and a third leg 222. The legs 220, 221, and 222 of the rear section 20 form, by way of example, an angle with a Z-profile. However, the rear section can also be constructed with more or fewer individual components.

[0070] The first side element 24 of, for example, a three-part rear section is attached to the central section 22, preferably by a material-bonded connection, for example by gluing or, more preferably, by welding. Each side element forms a receptacle for a crossbeam of a grate substructure, on which the rear sections 20 with their side elements 24, 26 (see figure) are mounted. Fig. 1) lie down.

[0071] The middle section 22 can lie against the back 18 in the area of ​​the transition from the first leg 220 to the second leg 221 and in the area of ​​the transition from the first leg 220 to the third leg 222. The middle section 22 can also lie against the back 18, for example, over a flat surface or not at all.

[0072] The first leg 220 can have at least one through-opening 62' (two through-openings 62' are shown as an example) and at least one through-hole 21. After the assembly described above, the through-channels 62' are arranged in the area of ​​the inlet 62 and an inlet 62 concealed by the central section 22. In this way, gas can flow through the gas line 60 despite the installed rear section 20. The through-hole 21 is arranged in the area of ​​the opening of the channel 32 on the rear side 18.

[0073] The bolt 30 is received by the through-hole 21 and the channel 32. The bolt 30 can have a through-channel 34 along the longitudinal axis 33 of the channel, a proximal inlet 31, and a distal outlet 35. A pressure plate 40 is located in the recess 70, with the pressure plate 40 bearing against the contact surface 71. The bolt 30 is detachably connected to the pressure plate 40, thereby detachably connecting the front section 10 and the rear section 20. The distal outlet of the bolt can be located in the mouth area of ​​the inlet 63, and the proximal inlet is located on the central section 22. The proximal inlet 31, the passage channel 34, and the distal outlet 35 allow gas to be transported from below the grate bar 1 through the bolt 30 into the gas passage 61 and up to the top 14 of the front section 10. The flow through the passage channel 34 can be improved by closing the opening of the recess 70 with a plug.

[0074] The Fig. 3 and Fig. 4 show views of one of the ones in the Fig. 1 and Fig. 2 similar embodiment of a grate bar shown. The description of the Fig. 1 and Fig. 2 can therefore also be applied to the, with the exception of the deviations described below. Fig. 3 and Fig. Read 4 (and vice versa). The top view of grate bar 1 ( Fig. Figure 3) shows the upper surface 14 of the front section 10 and a top view of the rear section 20. The upper surface 14 can, for example, have two slot-shaped outlets 69 and, for example, two circular outlets 64, 65. The slot-shaped outlets 69 extend transversely across the upper surface 14, where "transverse" means that the slots run at least approximately parallel to the grate bar's transverse axis 4 or at a small angle to it. The circular outlets 64, 65 can be arranged centrally. At least one outlet could also be located on the front side. The rear section 20 is located on the rear 18 of the front section 10. The top view of the rear section 20 shows the upper side of the second leg 221, as well as the upper sides of a first side element 24 and a second side element 26. The side elements 24, 26 are attached to the second leg 221.

[0075] The underside 12 (see below) Fig. 4) The front section 10 has a common edge with the front 16 and the rear 18. In the area of ​​the front 16, the front section 10 has a shoulder 13 (which can also be omitted). The underside 12 includes two inlets 67 as an example of at least one inlet 67, and a recess 70 extends from an opening in the underside 12. The recess 70 can function as an additional gas inlet. The recess 70 includes a contact surface 71 against which a pressure plate 40 is placed. A connecting element 30, here by way of example a bolt 30, fastens, for example by clamping, the rear section 20 to the front section 10 by positively engaging the bolt 30 with the pressure plate 40.

[0076] The view of the underside of the rear section 20 shows a second leg 221, a third leg 222, a first side element 24, and a second side element 26. The underside 12 of the front section 10 rests on the third leg 222. The first side element 24 and the second side element 26 are attached at least to the second leg 221 (i.e., to the first, second, and third legs 220, 221, 222, preferably to the second leg 221, and particularly preferably to the first and second legs 220, 221).

[0077] In Fig. Figure 5 shows a longitudinal section of a schematic partial view of another embodiment of a front section 10 of a grate bar 1. Again, the description of the Fig. 1 to 4, except for the following special features, also apply to the embodiment according to Fig. 5. Read (and vice versa).

[0078] The partial view of front section 10 in Fig. Figure 5 shows front 16, top 14, bottom 12, and the recess 70. The bottom 12 has a shoulder 13. The longitudinal section reveals a gas channel 61 curved towards the front 16 and two similarly curved gas passages 68. The two gas passages 68 extend from an inlet 67 in the bottom 12 to an outlet 69 in the top 14.

[0079] The optional gas channel 61 extends from an inlet 63 in the recess 70 to an outlet 65 in the top 14.

[0080] Both the gas channel 61 and the gas passages 68 are curved in the direction of the front face 16 in a region adjacent to the upper surface 14. A tangent 80 can be drawn to the lower side of the gas channel 61 and the gas passages 68, respectively. These tangents 80 form an acute angle 82 with the upper surface 14 (see figure). Fig. 2) out. As the distance of the point of attachment of the tangent 80 to the outlet 69 decreases, the value of the acute angle 82 formed by the tangent 80 and the top surface 14 decreases continuously, and the gas channel 61 and the gas passages 68 transition continuously into the top surface 14 at the respective outlet 65, 69.

[0081] Fig. Figure 6 schematically shows the rear end of a grate bar 1 with a rear section 20 which is attached to the rear 18 of a front section 10 via connecting elements 30, 40. For this purpose, the front section 10 has a recess 70 in its underside 16, extending towards the upper side 14. A channel 32 with a longitudinal axis 33 opens into the rear boundary of the recess 70. The connecting element 30, shown here as an example bolt, extends through the channel 32. The rear end 308 of the connecting element 30 passes through an opening 295 of the rear section 10 and rests against it with a radial projection (with the optional insertion of a spring washer, a flat washer, etc.). The front end of the connecting element 30 is shown here as being connected via a thread to a pressure plate 40, which is supported on the rear boundary of the recess 70, i.e. on a contact surface 71.As an alternative to screwing, other joining techniques (pressing, wedging, fabric bonding, etc.) are of course also possible.

[0082] The reverse side 18 of the front section 10 in Fig. Section 6 has a concave segment 181 that is curved with a first radius. A leg of the rear section 20 with a convexly curved surface 226 abuts this first segment 181. The convexly curved surface 226 has a smaller radius of curvature than the concave segment 181. Accordingly, in the event of a sudden load on the grate bar, the connection can yield elastically, with the connecting element 30 acting as an elastic restoring element. This prevents an overload of the ceramic front section 10, which would lead to its breakage.

[0083] The return section 20 in Fig. 6 is different than in the Fig. 1 to 4 are manufactured in one piece. The one in Fig. The rear section 20 shown in section 6 can also be connected to the front sections 10 according to the Fig. 1 to 4 can be mounted and also allows the grate bar 1 to be hooked into a crossbeam of a substructure. Accordingly, the return section 10 can be in Fig. 6 against a back section after one of the Fig. 1 to 5 can be replaced.

[0084] The return section 20 in Fig. Section 6 has a downwardly open profile 29, i.e., it has a downwardly open opening 28. The grate bar 1 can be suspended from the opening 28, for example, in a crossbeam, although other fastening options are also possible (e.g., bolting, welding, etc.). Similarly, the rear section 20 can form and / or have a downwardly open U-profile 29, at least approximately. In this case, the free end of the rear first leg 291 of the profile preferably points at least approximately downwards. A middle leg 292 extends forward from the first leg 291, which then transitions into a front (third) leg 293. The front side of the front leg forms the convex surface 226 already described. At the lower end of the front leg 293, a projection 296 preferably extends forwards, which can serve as a support for the underside 16 of the front section 10.

[0085] The free end of the rear free leg of the rear section 20 preferably has a mounting recess 294 extending from the channel axis 33. The optional mounting recess 294 is preferably located in the extension of the opening 295 in the opposite leg 293, i.e., in the assembled state, the mounting recess 294 is preferably located at least approximately in the extension of the longitudinal channel axis 33. This makes the rear end of the connecting element 30 easily accessible for an assembly tool.

[0086] Fig. 7 and Fig. Figure 8 shows an alternative front section of a grate bar front section 10 which is otherwise as in the Fig. 1 to 5 can be trained. The description of the Fig. 1 to 4 and 8 to 9 also read accordingly on the Fig. 7 and Fig. 8. Therefore, only differences will be discussed below: Front section 10 can, as in the Fig. 6 and Fig. As shown in Figure 7, the component has a recess 70 in its front section on the underside 12, extending towards the top side 14. A channel 32 can extend from the recess 70 along a longitudinal channel axis 33. The optional channel 32 connects the recess 70 to the front side 16 in this example and is shown here as a downward-facing channel 32, i.e., open towards the underside 12. Such a downward-facing channel 30 is particularly easy to manufacture and improves the cooling of the connecting element 30. Alternatively, the channel 32 can also be configured as shown in the figures. Fig. 1 to 6 may be trained. Likewise, channels 32 can be trained according to the Fig. 1 to 6 are designed as downward-opening channels 32.

[0087] As in the Fig. As shown in Figure 8, a front panel 160 can be attached to the front 16 by means of the connecting element 30. A front section 306 of the connecting element 30 extends through a recess in the front panel 160 and rests against the front 161 of the front panel 160 with a radial projection (here with an optional spring washer, a flat washer, or the like interposed). The rear end 308 of the connecting element can be supported against the wall of the recess 70 by means of a pressure plate 40. Fig. Figure 7 shows the pressure plate 40 integrated into an optional skid 90 as an example.

[0088] As in the Fig. 7 and Fig. As can be clearly seen in Figure 8, the front surface 16 of the front section 10 can have at least two segments 161, 162. In this example, the front plate 160 is at least approximately flush with at least one of the two segments 161, 162. The surface normal of this first segment 161 is preferably at least approximately parallel to the longitudinal axis 33 of the channel. Accordingly, when the front plate 160 is clamped against the front surface 16, compressive forces are introduced into the front section 10, at least substantially. As shown, a second segment 162, angled relative to the first, can be attached to this first segment 161. The angled segment can optionally form an overhang.

[0089] The optional skid 90 (see Fig. 8) can, for example, have a bracket with, for example, three legs 91, 92, 93. One leg engages with a section that also forms, at least partially, the pressure plate 40 in the recess 70 of the front plate. An angled second leg 92 can be attached to this first leg 91. The second leg 92 can have a bottom surface 922, which can then form the underside of the skid 90. The skid 90 can then rest, for example, slidably on a support with the bottom surface 12 or with a section of the bottom surface 12. The top surface 14 of a front section positioned in the conveying direction can, for example, serve as the support. The second leg 91 transitions via a further angle preferably into a third leg 93. For example, with an end surface of the third leg 93, the skid 90 can support the front section 10 on its underside 12.In the example shown, the front section 10 therefore rests on an upward-pointing end of the third leg 93.

[0090] Fig. 9 and Fig. Figure 10 shows a schematically simplified version of another variant of a grate bar in its assembled state ( Fig. 9) or as an exploded view ( Fig. 10). Like all other variants described herein, the grate bar 1 has a grate bar front section 10 and a grate bar rear section 20. Optional gas channels 61 as well as optional gas passages 68 as in the Fig. Items 1 to 8 are omitted from this version for simplification purposes only, but can also be included. The same applies accordingly to the optional clamping device 50 and at least one optional transverse hole in the front third of the front section 10 for receiving at least one clamping device 50, as well as for attaching an optional bracket 90 and / or a front plate 160 as shown. Fig. 7 and Fig. 8.

[0091] The front section 10 has a recess 70 in its rear third that is open to the rear and downwards (cf. Fig. 10). The recess 70 is bounded above and laterally by the preferably ceramic material of the front section 10. That is, the front section has at least one web 19 that bounds the recess laterally. The webs 19 can, for example, be bounded inwards by opposing inner surfaces 191 and outwards by the side surfaces 15 of the front section 10. Each of the two webs 19 is penetrated by a transverse channel 32. The two transverse channels have a common longitudinal axis 192. In this example, the recess 70 has the function of the channel 32 in the Fig. 2, Fig. 6 and Fig. 7 and could also be described as such. The transverse channel 32 has the function of the recess 70 in the Fig. 2, Fig. 6 and Fig. 7 and could therefore also be described as such.

[0092] A preferably metallic hook 20 can preferably be inserted into the recess 70, at least approximately flush (see below). Fig. 9 and Fig. 10). The hook 20 forms the return section 20. The return section 20 has, for example, a claw-like, downwardly open opening 28 with which the grate bar can be hooked into a crossbeam. The return section 20 also has a through hole 21, which here is designed as a transverse hole (see figure 10). Fig. 10). In the assembled state (see Fig. 9) A transverse bolt 30 sits in the through hole 21 and the two transverse channels 32. The pivot angle of the return section 20 about the transverse axis 192 is limited by contact surfaces 71. The contact surfaces 71 limit the recess 70 upwards and downwards.

[0093] The Fig. 11 and Fig. Figure 12 schematically illustrates another variant of a grate bar in its assembled state ( Fig. 11) or as an exploded view ( Fig. 12). This variant is very similar to the one in the Fig. 9 and Fig. Variant 10 shown. The description of the Fig. 9 and Fig. 10 is therefore also on the Fig. 11 and Fig. 12 to read. The main difference between the two variants is that the variant after the Fig. 11 and Fig. 12 has two hooks 20 which together form the return section 20. These two hooks 20 each sit in a recess 70 which, unlike in the Fig. 9 and Fig. 10 is also open on one side, i.e., between the two recesses, the front section 10 forms at least one web 19 with at least one through-hole 32. The two hooks 20 are fastened in each of their respective recesses 70 by means of a bolt 30. The embodiments according to the Fig. 9 and Fig. 11 can also be combined, i.e., for example, three (or more) hooks 20 can be provided, each seated in a recess 70, between which preferably at least one optional web 19 extends. The two lateral recesses 70 in the Fig. 11 and Fig. 12 can be closed laterally, e.g. by a further bridge 19 (cf. Fig. 9 and Fig. 10) The bolt 30 has been described here as a single piece, i.e., one bolt fixes the hook(s) 20. Alternatively, two or more bolts 30 may be provided, which are inserted into the Fig. 9 to 12 serve as pins for absorbing forces acting in a radial direction. For example, at least one bolt 30 can be provided for each hook 20. The term "bolt 30" should therefore be understood as "at least one bolt 30". Reference symbol list 1 grate bar 2 grate bar longitudinal axis 3. High axis of the grate bar 4. Cross-axis of the grate bar 10 Roststab front section, in short: front section 12 Subpage Paragraph 13 14 Top 15 side surface 16 Front 160 Front panel 161 first segment of the front 16 162 second segment of the front 16 18 Back 19 Bridge 191 interior surface 192 axle 181 concave surface segment 20 Grate bar back section, in short: back section 21 Through hole 22 Middle section 226 convex surface segment 24 first page element 26 second page element 28 Opening 29 Profile 291 first profile leg 292 Middle leg of the profile 293 second profile leg 294 Mounting recess 295 Opening for fasteners 296 lead 30 bolts / connecting element 306 front section / front end of the connecting element 308 rear section / rear end of the connecting element 31 proximal inlet 32-channel 33 Longitudinal axis of the canal 34 Through channel 35 distal outlet 40 printing plates 50 clamping devices 60 Gas pipeline 61 Gas channel 62 Admission 62' Passage opening 63 Admission 64 Outlet 65 Outlet 66 insulating bodies 67 Admission 68 Gas passage 69 Outlet 70 Exclusion 71 Plant area 80 Tangent 82 acute angle 90 runner 91 first thigh 92 second thigh 922 Underside of the runner, e.g., underside of the second leg 92 93 third thigh 220 first thigh 221 second thigh 222 third thigh

Claims

[1] A grate bar front section (10) for mounting on a grate bar back section (20) to form a grate bar (1) for example for a waste incineration plant, wherein the grate bar front section (10) has a refractory mineral material and a top (14), a bottom (12), a front (16), two narrow sides, and a back (18) and a grate bar longitudinal axis (2) extending parallel to the top (14) through the front (16) and the back (18), characterized by , that - a recess (70) extends from the underside (12) towards the top (14), - the recess (70) has at least one contact surface (71) for introducing a force acting in the direction of the rear (18) and / or the front (16) into the grate bar front section (10), and - at least one channel (32) with a channel longitudinal axis (33) connects the rear (18) and / or the front (16) and / or at least one side surface 15 with the recess (70), wherein the channel (32) can accommodate a bolt (30) or other connecting element for fastening the front section (10) to the rear section (20) and / or to a front plate (160). [2] A grate bar front section (10) according to claim 1, characterized by , that the channel (32) is at least partially open to the underside (12). [3] A grate bar front section (10) according to claim 1 or 2, characterized by , that at least one gas line (60) extends from the rear (18) towards the top (14) and / or front (16), wherein the gas line (60) has an inlet (62) at the rear (18) and an outlet (64) at the top (14) and / or front (16). [4] A grate bar front section (10) according to claim 3, characterized by, that at least one section of the gas conduit (60) is located above a plane, wherein the plane is parallel to the longitudinal axis (2) of the front section of the grate (10) and above the channel (32). [5] A grate bar front section (10) according to any one of the preceding claims, characterized by , that at least one section of an insulating body (66) extends between the channel (32) and the top (14) and / or between the recess (70) and the top (14). [6] A grate bar front section (10) according to any of the preceding claims, characterized by , that at least one gas passage (68) extends from the bottom (12) towards the top (14) and / or front (16), wherein the gas passage (68) has an inlet (67) in the bottom (12) and an outlet (69) in the top (14) and / or front (16). [7] A grate bar front section (10) according to claim 6, characterized by, that the gas passage (68) has a longitudinal axis which forms an acute angle with the top or front (14). [8] A grate bar front section (10) according to claim 6, characterized by , that - the gas passage (68) is curved towards the front (16) at least in an area adjacent to the top (14), - an acute angle (82) is formed between the top and a tangent (80), - the tangent (80) to the lower side of the gas passage (68) in the area adjacent to the upper side (14) is applied to an attachment point, and - the value of the acute angle (82) decreases with decreasing distance of the point of application of the tangent (80) from the outlet (69). [9] A grate bar front section (10) according to claim 8, characterized by, that the value of the acute angle (82) decreases continuously with decreasing distance of the point of contact from the outlet (69) and / or that the gas passage (68) at the outlet (69) continuously transitions into the top surface (14). [10] A grate bar front section (10) according to any one of the preceding claims, characterized by , that the top (14) has a greater longitudinal extent than the bottom (12), causing the back (18) and / or the front (16) to have an overhang. [11] A grate bar back section (20) for mounting on a grate bar front section (10), in particular on a grate bar front section (10) according to one of the preceding claims, in order to form a grate bar (1) in particular for a waste incineration grate by mounting, wherein the grate bar back section (20) has a middle part (22), a first side element (24) and a second side element (26), characterized by , that - the middle part (22) has at least a first leg (220) and a second leg (221), wherein the first leg (220) and the second leg (221) form an angle profile, - the first leg (220) has at least one through hole (21), and - one of the two side elements (24,26) is attached to each of the two long sides of the middle part (22). [12] Grate bar return section (20) according to claim 11, characterized by , that the first leg (220) has at least one through-opening (62'). [13] Grate bar return section (20) according to claim 11, characterized by , that the middle part (22) has a third leg (222). [14] Grate bar return section (20) according to claim 13, characterized by , that the second leg (221) and the third leg (222) point in opposite directions within ± 30°, with the first leg (220) being the middle leg. [15] A gridiron (1), characterized by, that the grate bar front section (10) according to one of claims 1-9 is detachably connected to a grate bar rear section (20) according to one of claims 11-14. [16] A grate bar (1) according to claim 15, characterized by , that at least one section of the grate bar back section (20) rests against the rear (18) and is fastened against the rear (18) by a fastening element (30) passing through the through hole (21) and the channel (32). [17] A grate bar (1) according to claim 16, characterized by that the fastening element (30) is attached by means of a pressure plate (40) resting against the contact surface (71). [18] A grate bar (1) according to claim 15 and claim 16, characterized by , that the fastening element (30) has a through channel (34) extending along its axis with a distal outlet (35) that terminates in the opening area of ​​an inlet (63). [19] Cement clinker cooler with a cooling grate or combustion plant with a firing grate, characterized by , that the corresponding grate has at least one grate bar front section (10) according to one of claims 1-10 and / or at least one grate bar rear section (20) according to one of claims 11-14 and / or at least one grate bar (1) according to one of claims 15 to 18.

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