JP4789007B2 - Ceramic liner, ceramic liner mounting structure, and ceramic liner mounting method - Google Patents

Description

  The present invention relates to a ceramic liner that is attached to a drift plate or the like of a vertical mill that crushes a raw material with a crushing roller, a ceramic liner attachment structure, and a ceramic liner attachment method.

  A vertical mill that pulverizes coal to form pulverized coal and supplies the pulverized coal as fuel to a coal fired boiler has a configuration as shown in FIGS. 7 and 8. In the vertical mill 101, a table 104 that is driven to rotate around a substantially vertical axis line by a motor (not shown) via a speed reducer 103 is disposed below a cylindrical casing 102. Above the table 104, A supply pipe 105 is provided which extends substantially coaxially with the axis of the table and drops the object to be crushed near the center of the table.

  Further, above the table 104, crushers 106 are provided at intervals of 120 degrees at three locations in the circumferential direction. The crushing device 106 rotates around a bracket 108 that is rotatably provided around a horizontal shaft 107 that is supported by the casing 102 and a roller shaft 109 that extends from the bracket 108 in a direction substantially perpendicular to the horizontal axis. A crushing roller 110 that is freely attached, and a reduction mechanism 112 that includes a blanker 111 that presses the bracket 108 by using fluid pressure and presses the crushing roller 110 against the rotating table 104 are provided.

  Accordingly, the object to be crushed such as coal introduced from the supply pipe 105 falls near the center of the table 104, moves in the peripheral direction of the table 104 by centrifugal force, and is caught between the table 104 and the pulverizing roller 110. Rarely, it will be crushed.

  Around the table 104, an air outlet 113 is provided for blowing up the conveying air upward, and the pulverized product generated by pulverizing the material to be crushed is a centrifugal force obtained by rotating the table 104. Therefore, the air is transferred to the outside in the radial direction of the table 104 and blown up by the conveying air blown out from the air outlet 113.

  A classifier 114 is disposed in the upper part of the case. The classifier 114 is an inverse conical cone portion 115 disposed around the supply pipe 105, and a classification in which the drive motor 116 rotates and drives the circumference of the supply pipe 105 in the cone portion 115 via a belt 117. The pulverized material blown up by the conveying air blown from the blower outlet 113 is introduced into the cone part 115 from the inlet 119 formed in the upper part of the cone part 115, and classified blades are provided. 118 is classified into fine powder having a small particle size and coarse powder having a large particle size, and the coarse particles fall on the table 104 from the lower part of the cone part 115 and are pulverized again. The fine powder is provided above the cone part 115. It is discharged through the discharged discharge pipe 120 and sent to a coal fired boiler.

  In such a saddle type mill 101, the drift plate 121 is fixed to the inner wall surface of the casing 102 at intervals of 120 degrees at three locations in the circumferential direction between the crushing rollers 110 around the table 104. . The drift plate 121 is provided at a portion facing the air outlet 113, deflects the flow of conveying air blown from the air outlet 113, classifies the pulverized charcoal, and returns the coarse powder to the center of the table for re-grinding. It has a function to make it.

  By the way, the above-mentioned drift plate 121 used for such a vertical mill 101 etc. has a plurality of ceramic liners (P-1 to P-16) 122 attached to the surface as shown in FIG. As shown by the ceramic liner shown in FIG. 10 (ceramic liner corresponding to P-10), the ceramic liner 122 includes a plurality of metal plates 123 except for a portion where the metal plates 123 are bolted. The ceramic piece 124 and a cushioning material 125 interposed between the metal plate 123 and the ceramic piece 124 are configured. More specifically, as shown in FIG. 11, the ceramic liner 122 heats a plurality of ceramic chips 124 via a cushioning material 125 made of neoprene rubber to a metal plate 123 made of rolled steel such as SS400. In a place to be bolted (a place where a ceramic chip is not provided), which is formed by pressure bonding with sulfur (baking), the bolt 127 is fastened to the base material 126 of the drift plate 121 and then bolted. The filler 128 was poured around the bolt head 127a at the above-mentioned location and the ceramic cover 129 was covered and adhered via the raw rubber 130 to protect the bolt head 127a.

  Conventionally, metal liners are also frequently used, and those described in Patent Document 1 or 2 are well known as metal liners and their mounting structures.

JP-A-5-319483 JP 2004-76032 A

  However, there are concerns about the following problems in the ceramic liner mounting structure shown in FIG. That is, as described above, the drift plate of the vertical mill is arranged between the pulverizing rollers and deflects the flow of the conveying air blown out from the air outlet 113 around the table 104, but is mixed in the blown up air. Since the pulverized charcoal strikes the surface of the drift plate 121 vigorously, if the ceramic cover 129 covering the bolt portion fixing the ceramic liner 122 is only bonded with the raw rubber 130, it will fall off due to the impact of the pulverized charcoal collision. However, the exposed bolt head 127a is worn and damaged, and the bolt 127 falls off, and the ceramic liner 122 falls off. For this reason, it is necessary to sufficiently increase the strength (wear resistance) of the portion covering the bolt 127.

  Moreover, since the air for conveyance which blows off from the blower outlet 113 becomes high temperature of 300 degreeC or more, in the structure mentioned above, the adhesion | attachment function of the raw rubber 129 which adhere | attached the ceramic cover 128 is lost, and the ceramic cover 128 falls off. There is also a disadvantage that a similar event occurs. For this reason, the covering structure of the bolt mounting location needs to have sufficient heat resistance.

  The present invention has been made in view of the above-described circumstances, and has a ceramic liner having good wear resistance and heat resistance against external impacts in a high temperature atmosphere, a ceramic liner mounting structure, and a ceramic. The main problem is to provide a method for mounting the liner.

  In order to achieve the above object, a ceramic liner according to the present invention is arranged except for a metal plate and a portion where the metal plate is bolted, and a welding hole is formed and provided in the welding hole. A ceramic chip welded to the metal plate via a welded member, a step that can be attached to a location where the metal plate is bolted and a bolt head can be accommodated, and a welding hole are formed. A bolt-covering ceramic chip having a non-step portion weldable to the metal plate via a welding member provided in the welding hole is provided.

  Therefore, if such a ceramic liner is used, the ceramic chip is not pressure-bonded by thermal vulcanization (baking) as in the past, but is fixed to the metal plate by welding, so that a strong assembled state can be obtained, In addition, since the bolted portion is covered with a ceramic chip having a stepped portion that accommodates the bolt head and a non-stepped portion that can be welded to the metal plate, the bolt head covering structure is strengthened and the ceramic chip is heated. Will not drop out.

  Therefore, such a ceramic liner mounting structure is arranged except for a metal plate and a portion where the metal plate is bolted, a welding hole is formed, and a welding member provided in the welding hole is provided. A ceramic liner having a ceramic chip welded to the metal plate via is bolted at a location where the bolt is fastened to a mounting location, and the bolt head can be accommodated in the bolted location. A bolt-covering ceramic chip having a step and a non-step portion formed with a welding hole is attached so as to accommodate the bolt head in the step portion, and the non-step portion is provided in the welding hole. It is what was welded to the metal plate via the welded member to be formed (Claim 4).

  Here, the hole for welding is preferably closed with a ceramic cap in order to protect the welded portion. Further, it is preferable that a buffer material is disposed between the metal plate, the ceramic chip, and the bolt covering ceramic chip so that the ceramic chip is not damaged during the welding of the ceramic chip.

  The above-described ceramic liner mounting method is arranged except for a metal plate and a portion where the metal plate is bolted, and a welding hole is formed and a welding member provided in the welding hole is used to form the ceramic liner. A ceramic liner having a ceramic chip welded to a metal plate is formed in advance, the ceramic liner is bolted to the mounting location at the location where the bolt is fastened, and the bolt head is accommodated at the bolted location. A bolt-covering ceramic chip having a portion and a non-stepped portion in which a welding hole is formed is attached so that the bolt head is received in the stepped portion, and the non-stepped portion is provided in the welding hole. The metal plate may be welded via a welding member. And after welding the said non-step part to a metal plate via a welding member, it is good to close the hole for welding of a non-step part with a ceramic cap.

  Therefore, a plurality of ceramic chips are pre-welded at the factory etc. except for the places to be bolted to the metal plate, the ceramic liner is transported and bolted to the mounting location, and a step is formed at the bolted location. The ceramic tip is attached so that the bolt head is accommodated in the stepped portion, the welding hole portion of the non-stepped portion is welded to the metal plate via the welding member, and then the welding hole portion of the non-stepped portion is attached. If it is closed with a ceramic cap, it becomes possible to attach a ceramic liner having wear resistance and heat resistance to the mounting location.

  As described above, according to the present invention, a ceramic liner, a ceramic liner mounting structure, and a ceramic liner mounting method capable of obtaining good wear resistance and heat resistance against external impacts in a high-temperature atmosphere. In particular, it is possible to sufficiently increase the strength (wear resistance) of the ceramic chip that covers the bolt that fixes the ceramic liner to the mounting location, and to sufficiently provide heat resistance.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS The best embodiment of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 shows a configuration example of a drift plate 2 of a vertical mill to which a ceramic liner 1 according to the present invention is attached. The drift plate 2 is fixed to the inner wall surface of the case 102 at three intervals in the circumferential direction between the crushing rollers 110 around the table 104 of the vertical mill 101 shown in FIG. It is provided at the part facing the air outlet 113, for deflecting the flow of the air for conveyance blown from the air outlet 113, for classifying the pulverized charcoal to inertia, and returning the coarse powder to the center of the table for re-grinding. is there.

  In this example, the plurality of ceramic liners 1 attached to the outer surface of the drift plate 2 are separately provided on the front outer wall surface in an upper stage, a middle stage, and a lower stage, and are attached so as to be substantially symmetrical. Is divided into three ceramic liners, P-1, P-2, and P-3, and in the middle, five sheets are P-8, P-9, P-10, P-11, and P-12. The upper part is divided into four ceramic liners P-13, P-14, P-15, and P-16. The left and right side surfaces are divided into two upper and lower ceramic liners (P-4 and P-7, P-5 and P-6), and no ceramic liner is provided on the upper surface.

  As shown in FIG. 1B, each ceramic liner 1 has a large number of ceramic chips 3, and for example, ceramic liners (P-9, P-10, P-11 shown in FIG. 2). Each ceramic chip 3 has various sizes as represented by a ceramic liner corresponding to the ceramic liner 3a, which is attached to a portion excluding a portion to be bolted, and a portion to be bolted is covered. There are two types of ceramic chips 3b for bolt covering.

  Each ceramic chip 3 is attached to a metal plate 4 serving as a base material via a cushioning material 5, and the ceramic chip 3 a attached to a portion excluding a portion to be bolted is shown in FIG. ), A welding hole 6 is formed, and a welding cap 7 inserted into the welding hole 6 is welded to the metal plate 4 to be fixed to the metal plate 5. Specifically, the opening end on the metal plate side of the welding hole 6 is tapered and narrowed, and the welding cap 7 is formed in a cylindrical shape corresponding to the tapered shape. The tip of the cap 7 is brought into contact with the metal plate 4 through a hole 5 b formed in the buffer material 5, and the ceramic chip 3 a is fixed to the metal plate 4 by welding this portion. Here, the buffer plate 5 interposed between the ceramic chip 3 a and the metal plate 4 is for preventing the ceramic chip 3 from being damaged when the welding chap 7 is welded to the metal plate 4. And in order to protect a welding location, the hole 6 for a ceramic tip 3a is obstruct | occluded by the ceramic cap 8 inserted here.

  On the other hand, as shown in FIG. 4A, the bolt covering ceramic chip 3b attached to the portion to be bolted can accommodate the bolt head 10a of the bolt 10 shown in FIG. 4B. 3 and a non-step portion 13 in which a welding hole 12 is formed, and, as shown in FIG. 3B, through a bolt mounting hole 4a formed in the metal plate 4. The head 10 a of the bolt 10 to be attached is attached so as to be accommodated in the step portion 11. And like the structure mentioned above, the ceramic chip 3b is fixed to the metal plate 4 by welding the welding cap 14 inserted in the welding hole 12 of the non-step portion 13 to the metal plate 4, and the welding location In order to protect the above, the welding hole 12 is closed by a ceramic cap 15.

  In addition, 16 and 19 are heat resistant inorganic adhesives, 18 is fillers, such as a silicone sealant. The metal plate 4 is made of rolled steel such as SS400, the buffer material 5 is made of fluoro rubber, the ceramic chip 3 is made of alumina having a thickness of about 20 mm, and the step portion 11 is A thickness of about 12 mm is also secured in the formed portion.

The operation of attaching the ceramic liner 1 to the drift plate 2 is performed as follows.
First, as shown in FIG. 5A, a metal plate 4 processed according to the size of each ceramic liner is prepared, and a bolt mounting hole 4a is drilled at a predetermined location to be bolted. Here, the bolt mounting hole 4a is preferably formed in a long hole in order to finely adjust the mounting position.

  Next, as shown in FIG. 5B, the surface of the metal plate 4 on the side where the ceramic chip is attached is roughened with a sander (left side of FIG. 5B), and the size of the metal plate 4 is measured from above. The cushioning material 5 (the right side of the figure (b)) cut according to the thickness is stuck with an adhesive. In addition to the through hole 5a through which the bolt 10 is inserted, the buffer material 5 is formed with a through hole 5b for welding the ceramic chip 3.

  Next, a ceramic chip 3a is prepared which is cut into a predetermined shape so as to be attached to a portion of the metal plate 4 other than the bolted portion and in which a welding hole 6 is formed at the predetermined location, and FIG. As shown in FIG. 4, the ceramic cap 3a is inserted into the welding hole 6 with a welding cap 7 inserted into a predetermined mounting location of the metal plate 4, and the welding cap 7 in the welding hole 6 is attached to the metal plate 4 as shown in FIG. Weld to. Then, when this welding is completed, the spatter and impurities in the welding cap are removed.

  Thereafter, each welding hole 6 is degreased with acetone or the like, and as shown in FIG. 5D, the heat-resistant inorganic adhesive 16 is filled therein, and the ceramic cap 8 is inserted. At this time, the adhesive protruding from the surface is wiped off, and heat treatment (around 150 ° C.) is performed to cure the adhesive.

  In order to attach each of the ceramic liners 1 (P-1 to P-16) to the drift plate 2 by welding the ceramic chip 3a to the portion of the metal plate 4 except the portion to be bolted in this way. Transport to the site.

  The ceramic liner 1 conveyed to the site is applied to a predetermined location on the surface of the drift plate 2, and the bolt mounting hole 4a formed at a location where the ceramic chip 3a is not mounted and the base material of the drift plate 2 The ceramic bolt 1 is bolted to the surface of the drift plate 2 by inserting the mounting bolt 10 through the mounting hole 20a formed in 20 and tightening with the nut 17 (FIG. 6A).

  Thereafter, the filler 18 is injected around the bolt head, and the ceramic chip 3b is attached to the bolted portion so that the bolt head 10a is accommodated in the step portion 11, and the welding hole of the non-step portion 13 is attached. A welding cap 14 is inserted into the portion 12, and this portion is welded to the metal plate 4 to fix the ceramic chip 3b to the metal plate 4 (FIG. 6B).

  In this way, after the portion to be bolted of the metal plate 4 is coated with the ceramic chip 4b, the welding hole 12 is degreased with acetone or the like in order to cover the welded portion, and the heat-resistant inorganic adhesive 19 is applied thereto. After filling, the ceramic cap 15 is inserted, and then the adhesive protruding on the surface is wiped off, and heat treatment (around 150 ° C.) is performed to cure the adhesive (FIG. 6C).

  Then, by repeating the above processing and attaching all the ceramic liners 1 to the surface of the drift plate 2 in a predetermined order, the operation of attaching the liner to the drift plate 2 is completed.

  Therefore, in the above-described configuration, each ceramic chip 3 attached to the ceramic liner 1 is fixed to the metal plate 4 by welding, so that a strong attachment structure can be obtained and heat resistance can be increased. Become. In particular, since the ceramic chip 3b covering the bolt mounting portion is fixed to the metal plate by welding so as to cover the bolt head 10a, the ceramic chip 4b will not fall off due to impact or heat. 10a is reliably protected and it is possible to prevent the ceramic liner 1 from falling off due to the breakage of the bolt. Furthermore, since the welded portions of the respective ceramic tips 3 are protected by the ceramic caps 8 and 15, it is possible to prevent the ceramic tips from falling off due to wear or breakage of the welded portions.

  In the above-described configuration, the case where the ceramic liner 1 is attached to the drift plate 2 of the vertical mill is shown. However, it is the same as the ceramic liner (liner) provided in another place that receives an external impact in a high temperature atmosphere. A configuration may be adopted.

FIG. 1 (a) shows the appearance of a drift plate to which a ceramic liner fixed around the table of a vertical mill is attached. Each ceramic liner is numbered, and FIG. 1 (b) These are figures which show each ceramic liner. FIG. 2 is a view showing an example of a ceramic liner, FIG. 2 (a) is a front view of the ceramic liner, and FIG. 2 (b) is a side view of the ceramic liner. 3 is an enlarged view showing a cross section of the ceramic liner, FIG. 3 (a) is an enlarged view showing a cross section taken along line AA of FIG. 2, and FIG. 3 (b) is a line BB of FIG. It is an enlarged view which shows the cross section cut | disconnected by. FIG. 4A is a view showing the ceramic chip 3b to be mounted at a place to be bolted. The upper part is a plan view thereof, and the lower part is a cross-sectional view taken along the line CC of the upper part. FIG. 4B is a diagram illustrating a bolt for attaching the liner. FIG. 5 is an explanatory diagram showing a process of forming a ceramic liner. FIG. 6 is an explanatory view illustrating a process of assembling the ceramic liner to the base material of the drift plate. FIG. 7 is a cross-sectional view showing an overall configuration showing an example of a vertical mill. 8A is a cross-sectional view taken along the line XX in FIG. 7, and FIG. 8B is a cross-sectional view taken along the line YY in FIG. 8A. FIG. 9 shows the appearance of a drift plate to which a ceramic liner fixed around the table of a vertical mill is attached. Each ceramic liner is numbered. FIG. 10 is a view showing an example of a conventional ceramic liner, FIG. 10 (a) is a front view of the ceramic liner, and FIG. 10 (b) is a side view of the ceramic liner. FIG. 11 is an enlarged cross-sectional view showing a configuration in the vicinity of bolting in a state where the ceramic liner is bolted to the base material of the drift plate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ceramic liner 2 Current drift plate 3 Ceramic chip 3b Ceramic chip for bolt coating 4 Metal plate 5 Cushioning material 6,12 Hole part for welding 8,15 Ceramic cap 10a Bolt head 11 Step part 13 Non-step part

Claims (8)

A metal plate, and a ceramic chip that is arranged except for a place where the metal plate is bolted, a welding hole is formed, and is welded to the metal plate via a welding member provided in the welding hole; The metal plate can be mounted at a location where the metal plate is bolted and a stepped portion and a welding hole are formed to accommodate the bolt head, and the welding plate is provided in the welding hole. And a ceramic chip for bolt coating having a non-step portion weldable to the ceramic liner. The ceramic liner according to claim 1, further comprising a ceramic cap that can be inserted into the welding hole. The ceramic liner according to claim 1, wherein a buffer material is disposed between the metal plate, the ceramic chip, and the bolt covering ceramic chip. A metal plate, and a ceramic chip that is arranged except for a place where the metal plate is bolted, a welding hole is formed, and is welded to the metal plate via a welding member provided in the welding hole; A ceramic liner having a bolt is bolted to the mounting location at the location where the bolt is fastened, and a stepped portion and a hole for welding are formed at the bolted location so that the bolt head can be accommodated. A ceramic chip for bolt covering having a portion is attached so as to accommodate the bolt head in the step portion, and the non-step portion is welded to the metal plate via a welding member provided in the welding hole portion. The ceramic liner mounting structure is characterized by that. 5. The ceramic liner mounting structure according to claim 4, wherein the welding hole is closed with a ceramic cap. 5. The ceramic liner mounting structure according to claim 4, wherein a buffer material is disposed between the metal plate, the ceramic chip, and the bolt covering ceramic chip. A metal plate, and a ceramic chip that is arranged except for a place where the metal plate is bolted, a welding hole is formed, and is welded to the metal plate via a welding member provided in the welding hole; A ceramic liner having a predetermined shape is preliminarily formed, and the ceramic liner is bolted to the mounting portion at the location where the bolt is fastened, and a step portion and a welding hole portion for accommodating the bolt head are formed at the bolted location. A ceramic chip for covering a bolt having a non-stepped portion is attached so that the bolt head is accommodated in the stepped portion, and the non-stepped portion is attached to the metal plate via a welding member provided in the welding hole portion. A method for mounting a ceramic liner, characterized by welding. 8. The welding hole portion of the non-step portion is closed with a ceramic cap after the non-step portion is welded to the metal plate via a welding member provided in the welding hole portion. How to install the ceramic liner.

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