WO1994008754A1

WO1994008754A1 - Grinding method and grinding system for billet

Info

Publication number: WO1994008754A1
Application number: PCT/JP1993/000218
Authority: WO
Inventors: Hiroyuki Matsumura; Yoshikazu Ikemoto; Keiji Tsujita; Hidetaka Tanaka; Kazumi Daitoku; Tomoharu Shimokasa; Fujiya Nogami; Kenji Minami
Original assignee: Kawasaki Jukogyo Kabushiki Kaisha; Nippon Steel Corporation
Priority date: 1992-10-21
Filing date: 1993-02-23
Publication date: 1994-04-28
Also published as: ES2134256T3; EP0645214A1; JPH06126630A; EP0645214B1; DE69325807D1; AU670573B2; AU3574893A; TW245673B; DE69325807T2; BR9305541A; KR0161671B1; EP0645214A4; CN1085840A; CN1095728C

Abstract

A grinding method, in which an abrasive material (6) is ejected from a nozzle (1, 108) onto a billet (3, W) so as to grind the same, and which is applied to a continuous casting step or a step subsequent thereto, which method is characterized in that abrasive material-mixed high-pressure water is applied in the form of a jet to the surface of a billet so as to grind a flaw-carrying portion (12, 12', 12'', 12''') thereof; and a grinding system for practising this grinding method, having a supply source (19-20, 103) of a high-pressure liquid and an abrasive material, a nozzle (4, 102) connected to the supply source, and a combination of an abrasive material recovering unit (104) for recovering as necessary the abrasive material, which has been used for a grinding operation, and returning the same to the supply source, and a flaw detecting means (15-16, 101).

Description

Description Billet grinding method and grinding system Technical field

The present invention relates to the grinding of a substrate surface, and more particularly to a method and a grinding system for grinding a flaw on the surface of a steel material in a continuous production line and a subsequent process.

Background art

Boules, slabs, billets, or slabs that are rolled in a continuous manufacturing process may have various flaws during the forging and rolling process. There is an inconvenience in the subsequent post-process, leading to a reduction in product yield and product quality.

In order to deal with this, the flaws are removed by maintenance work during the production of slabs such as slabs, blooms and billets, and the slabs from which the flaws have been removed are continued. It is supplied to the post-process to prevent a decrease in product yield and product quality. ₍ However, as a means of gauging the billet, hot scarf cutting and grinding are used. Grinding with a hot head scarf is generally used, and the former hot scarf cutting is performed by, for example, a portal frame as disclosed in Japanese Patent Application Laid-Open No. 52-56444. Japanese Patent Laid-Open Publication No. H08-27139 discloses a crater operating table having two or more craters mounted vertically and horizontally on a support beam on the side surface where two beams are arranged in parallel, and a plurality of craters. Japanese Patent Application Publication No. 52-810, No. 48, No. 8: Uses multiple torches arranged in a row to perform ablation to remove wide defects without performing auxiliary ablation. Are disclosed.

As for the grinding by a grinder, for example, as disclosed in Japanese Patent Application Laid-Open No. 48-46993, a grinding wheel is ground using a hydraulic cylinder or an air cylinder. To improve grinding performance, such as grinding of a billet or the like, or a stainless steel piece, a stainless steel billet as disclosed in Japanese Patent Application Laid-Open No. H11-242729. A method has also been devised to grind the steel with a grinder in a specific temperature range, to avoid the self-hardening of the stainless steel, and to remove defects effectively. .

Furthermore, in addition to the above-mentioned means for removing flaws such as hot cutting using a hot scarf and grinding using a grinder, the method mainly used for descaling at the stage of producing a billet includes, for example, As in the invention disclosed in Japanese Patent Application Laid-Open No. 51977984, a predetermined abrasive is wet-sprayed from a nozzle onto the surface of a stainless steel plate to perform both grinding and descaling. Various types of slab care means such as have been proposed.

However, the various slab care methods described above have various problems as described below.

First, as in the invention disclosed in Japanese Patent Application Publication No. JP-A-5-26464, which relates to scarf cutting, the side where two portal frame beams are arranged in an equilibrium manner, and the crater operation table supported on the upper surface A crater operation table with multiple craters mounted on the beam so that it can be moved vertically and horizontally As described in Japanese Patent Application Laid-Open No. Sho 52-81048, a wide defect can be formed by performing ablation using a plurality of torches arranged in a row and performing auxiliary ablation. In such a method, the hot scarf work itself is accompanied by high temperature and high dust, so that not only the work scarcely deteriorates the working environment but also the hot scarf work. However, it is difficult to determine the flaws remaining on the surface of the machined steel slab after the heat treatment.

Furthermore, in the hot scarf method, it is impossible to control the depth of cutting, which causes uneven cutting. There is a disadvantage in that the amount of hot scarf increases, resulting in a decrease in yield.

In addition, such a hot scarf method requires large-scale equipment compared to other methods when automation is used to improve the working environment and improve work efficiency, which is economically expensive. is there.

In addition, as disclosed in the above-mentioned invention of Japanese Patent Application Laid-Open No. 48-46993, a grinding wheel is ground using a hydraulic cylinder or an air cylinder. For improving grinding performance and grinding of billets etc. As in the invention disclosed in Japanese Patent Application Laid-Open No. H11-242927, the stainless steel slab and the stainless steel slab are ground with a grinder. When grinding, the method of cleaning the grinder within a specific temperature range also requires work in a bad environment of high temperature and high dust generation, similar to the hot scarf method described above, depending on the type of billet. And after grinding As described above, it is difficult to determine the flaw defect remaining on the surface, and this has disadvantages such as extremely high flaw removal cost.

If the width of the grinder is increased, the amount of unnecessary shaving increases, the driving force increases, the running cost increases, and the yield decreases. Therefore, when the width of the grinder is reduced, the efficiency is reduced, a large amount of grinder is required, and the maintenance time is not long, which is not preferable. 5 1-9 7 8 9 4 As in the invention disclosed in JP-A No. 4-9, a method of removing and removing flaws on steel slabs, such as grinding and descaling by spraying abrasives from nozzles on the surface of stainless steel plates in a wet manner At present, the latter is mainly used for descaling, and is technically insufficient to grind and remove flaws on steel slabs, and cannot be practically adopted.

The purpose of the invention of this application is to solve the problems of slab maintenance based on the above-mentioned conventional technology, and the slab after grinding is important for improving the working environment and automation. In addition to being able to easily determine the flaw defect remaining on the surface of the piece, the flaw defect part can be selectively removed according to the state of the flaw defect, thereby reducing the cost of the product. The aim is to provide an excellent method of grinding slabs that can improve the yield, improve the quality of products, and ensure the quality of products by utilizing the processing technology in the steelmaking industry. It is.

Disclosure of the invention

The grinding method according to the invention of this application solves the above-mentioned problems. For this purpose, ultra-high-speed water is used in a state in which predetermined fine-grained abrasives such as garnet sand, silica sand, aluminum, iron sand, and iron grid are mixed in high-pressure water at a predetermined pressure. By jetting it as a jet with a small diameter of a predetermined small size continuously from the nozzle and projecting it impingingly on the surface of a slab or other steel piece As a product existing near the surface of the billet, harmful defects and flaws are automatically ground and removed in a non-contact manner. Further, before or after grinding, or both. By automatically sensing the surface of the billet and the vicinity of the surface, and adding a function to search for the presence and location of defects and flaws, complete automation of the grinding line is achieved. It takes technical measures to make it unmanned.

In addition, the grinding system according to the present invention further develops conventional wet blasting and liquid honing to increase pressure (typically 300 kgf / cm ² or more) and improve energy density. A grinding system for the surface of a base material, such as a steel slab, using an abrasive wafer with improved measuring and processing efficiency.A defect detection system that detects flaws on the surface of the base material, and a defect detection system for the same A grinding control system that sends controlled grinding conditions based on flaw information detected from the system, an abrasive supply system that controls the supply of abrasive based on signals from the grinding control system, and a grinding control system A grinding nozzle device system provided with a nozzle that moves relative to the base material based on the signal of the base material, and an abrasive collection system that collects the abrasive after the grinding process and returns it to the abrasive supply system are required. Depending on the system You. As a defect detection device used in a defect detection system for detecting flaws on the surface of a base material, magnetic particle flaw detection, ultrasonic flaw detection, an image processing apparatus using a television camera, or the like can be used. Grinding with an abrasive water jet is a non-thermal processing method and does not cause any thermal effects or blurring of surface defects due to melting of the material surface, so flaw detection after processing The grinding wheel is easy because it is easy to machine, and the machining is easy with 0 N / 0 FF. Since there are few problems related to tool life as in the case of (1), an automation system can be easily constructed.

In addition, if the used abrasive recovery system is connected to the abrasive supply system mixed with the high-pressure fluid jet, the abrasive water jet can be used in a wide area. When applied to continuous surface grinding, a circulating system for abrasives is established. Continuous operation can be performed even when abrasive wafers that move relative to multiple substrates are applied to the grinding of wide substrate surfaces.

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 is a schematic diagram of a grinding mode showing the principle of grinding of abrasive water jets.

FIG. 2 is a schematic view of a grinding mode showing partial depth grinding by an abrasive water jet.

Fig. 3 is a schematic diagram showing the grinding mode of surface grinding by abrasive wobble jet. FIG. 4 is a cross-sectional view showing a main part of a grinding system according to the present invention for performing surface grinding of a slab material,

Fig. 5 is a sectional front view of the same part,

Fig. 6 is a plan view showing the defect on the surface of the slab material and the movement of the nozzle.

Fig. 7 is a longitudinal sectional view of the same,

FIG. 8 is a block diagram showing a slab material grinding system according to the present invention,

FIG. 9 is a plan view of a slab material grinding system according to the present invention.

Fig. 10 is a front view showing the main parts of the grinding system shown in Fig. 9,

Fig. 11 is a side view showing the main parts of the grinding system shown in Fig. 9,

FIG. 12 is a block diagram showing another embodiment of the present invention, FIG. 13 is a plan view showing the embodiment shown in FIG. 12, and FIG. 14 is a diagram shown in FIG. FIG. 15 is a front view showing the essential parts of the embodiment shown in FIG. 13;

FIG. 16 is a side view showing a main part shown in FIG. 15 in the best mode for carrying out the invention.

Figs. 1 to 3 are schematic diagrams of the principle of grinding of artificial slabs by a high-pressure water jet (abrasive water jet) mixed with an abrasive. This is a nozzle of a cutting device, and is finely divided into high-pressure water of a predetermined pressure supplied to a mixing chamber (not shown), for example, garnet sand, quartz sand, aluminum, iron sand, iron iron. An abrasive such as a grit is mixed in to form a small-diameter jet 2 of a predetermined small size, which is injected at an ultra-high speed onto a slab material 3 of a billet to be polished. The various modes of cutting (grinding) when the traverse speed (nozzle feed speed or feed speed of the slab material 3) of the nozzle 1 relative to the slab material 3 is increased (slowed) are shown. are doing.

Thus, FIG. 1 shows a mode used for normal cutting in which the entire thickness t of the slab material 3 to be ground is cut via grinding, and the relative speed region is the slab material 3. The drag line 4 is formed over the thickness t of the slab material when a sufficient low-speed region that can be cut well is used.

On the other hand, Fig. 2 shows the case where the nozzle 1 and the slab material 3 are relatively moved at a higher speed than in the case of Fig. 1, and cutting is performed up to the bottom of the slab material 3 with the thickness t. In this case, the cutting depth is periodically changed at the bottom of the cutting by the difference of Δh, at the cutting phenomenon.

Figure 3 is Ri der If you cormorants by performing traverse at higher speed relative speed between Roh nozzle 1 and the slab member 3 Ri by the case of FIG. 2, the cutting depth h ₂ is Naru rather shallow, bottom depth change delta h ₂ is minor, therefore, cut the groove bottom Ri Do Ni will I be smoothed, is an aspect Do that enables so-called groove switching grinding.

Thus, the invention of this application is an abrasion water evening. This method applies the grinding principle and the cutting speed range that require an enthusiast to the surface grinding of the billet slab material.

Also, in the invention of this application, by using the above principle, the surface of the slab material 3 of the billet is made of abrasive grains of the abrasive in an ultra-high-speed jet jet in which the abrasive is mixed in high-pressure water. The erosion effect on the slab material 3 makes it possible to remove the defect in an ideal state without heat generation, even though it is microscopic, even though it is microscopic. Become.

The surface of the billet slab material 3 can be made uniform or at the surface or in the vicinity of the flaw defect site depending on the relative feed operation of the nozzle 1 that forms the jet jet described above. Can be partially and selectively smoothed through grinding.

Then, the surface of the slab material 3 of the billet, or the system up which detects defects etc. before, after, or both of the above-mentioned grinding, or both are used. The presence / absence, position, and size of flaws in the vicinity can be detected, and this can be input or feed-knocked as information to cope with grinding. This makes it possible to stabilize and reliably assure the process of removing defects and flaws on the surface of steel slabs, and furthermore, it is possible to achieve complete automation of the work process. I can do it.

Also, since the ground surface of the slab after grinding is not covered with oxide scale, etc., it is relatively easy to check for defects after cutting. Become. Next, an embodiment of the invention of this application will be described with reference to FIG. 4 and subsequent drawings.

In the following description, the same parts as those in FIGS. 1 to 3 are denoted by the same reference numerals and described.

FIGS. 4 and 5 show the grinding mode of the slab material 3 of the billet and the structure of the nozzle head 4 in one embodiment of the invention of the present application. In the abrasive nozzle head 4, abrasives 6 such as garnet sand supplied by a hose 5 etc. are generated by a water nozzle 8 connected to a high-pressure water pipe 7. The negative pressure generated by the Venturi effect of the high-speed water jet 9 is sucked and supplied to the mixing chamber 10 using the negative pressure generated by the venturi effect. The water jet 9 and the abrasive 6 are mixed and accelerated inside the abrasive nozzle 1 to be ejected, so that the jet 2 has a smaller diameter than the abrasive nozzle 1 and has a smaller diameter than that of the abrasive nozzle 1. The slab material 3 that is projected onto a predetermined part of the slab material 3 and moves relatively Grinding it's in the processing principle.

In this case, while maintaining the axis of the abrasive nozzle 1 at an appropriate angle with respect to the slab material 3 according to the type of the slab material 3, an appropriate speed and pitch so as to sufficiently cover surface defects and the like are provided. By moving the slab material 3 relatively to the slab material 3 while swinging or rotating by feeding, predetermined grinding and the like can be performed.

According to the experiment, the abrasive was supplied at 0.5 Jig Z min or more. When high pressure water is supplied at a pressure of 100 kgf / cm or more and a flow rate of 2 ^ / min or more and the injection distance between the nozzle and the billet is set within 200 mm, for example, slab material The projection angle to 3 is 10 to 170. The relative speed between the slab material 3 and the abrasive nozzle 1 during the swinging and rotation of the abrasive nozzle 1 is about 1 to 10 mZ min, and extremely good results can be obtained. did it. However, these conditions are slightly different depending on conditions such as the type of the abrasive 6.

FIGS. 6 and 7 further illustrate an example of the operation method of the abrasive nozzle 1 described above. As shown in the figures, the defects 1 2, 1 2 ′, 1 2 ′, 1 2 ′ ′ As for the method of swinging the abrasive nozzle 1 with respect to ′, various combinations of the cutting range, direction, and pitch feed for the slab material 3 can be adopted as shown in the figure.

In the embodiment shown in FIG. 7, the boundary between the ground portion 3 ′ and the unprocessed portion 3 with respect to the defects 12, 12 ′, 12 ″, 12 ′ and 12 ′ ″ shown in FIG. However, it is appropriately rounded so as not to cause an extreme thickness difference (step).

And, the abrasive nozzle 1 can be ground in the same manner as described above by a rotary motion having an appropriate radius and a pitch feed instead of the swing.

Next, Fig. 8 is a block diagram showing the entire system including the inspection process. In this embodiment, an articulated robot is used as the driving device 13 of the abrasive nozzle 1. Inspection stage 1 before grinding The search results obtained in step 4 are used as the positional information (location, size, depth, etc.) of the polishing of the defects 12 etc. of the slab material 3 by the defect detection mechanism 15 such as the CCD camera. Defect detection system. Input to 16 and the grinding (scarfing) stage 17 automatically performs the grinding accordingly.

In the grinding surface determination system, the television camera is scanned over the entire surface of the continuous steel slab by the force roller drive device operated by the signal from the force roller drive control device, and the information is imaged. The position, including the size, shape, area, depth, etc., of the flaw is converted by the processing equipment into coordinates corresponding to the slab surface, and the addresses are converted to the slab surface based on these coordinates. I do. The information from this image processing device is input to the general control computer, and the information on the shape, depth, grinding range, procedure, and position of the flaws input is driven and instructed by the grinding system. By controlling and driving the slip drive control device and the drive device and the abrasive mixing and high-pressure water control device, the high-pressure fluid nozzle for abrasive injection is scanned over the steel slab by an addressing guide mechanism. Shave.

In addition, if necessary, inspection during and after grinding is performed by optical means in combination with the defect detection mechanisms 15 ′, 15 ′ '' and the defect detection system 16, and the results are ground. It can be used for feedback inside or for re-grinding.

In this embodiment, a method is employed in which the used abrasive 6 is collected, supplied to the abrasive supply device 19, and reused. Then, the abrasive, which has been pulverized into fine powder and atomized, is separated and removed by a collecting and re-transmitting device 18.

20 is a high-pressure water generator, 7 'is a high-pressure water pipe, 21 is a nozzle drive controller, 22 is an overall grinding controller, 23 is a discarded abrasive, and 24 is a new abrasive. Abrasive, 25 is the inspection stage. FIGS. 9, 10, and 11 show the appearance of the entire system of the embodiment shown in FIG. 8, and the system has a continuous contact time of 7 minutes on average. In this mode, three articulated robots perform a cooperative operation to grind the surface of a slab material 3 of a billet. The slab material 3 is transported in the direction of the arrow.

Next, another embodiment of the present invention will be described with reference to FIG. 12 to FIG.

In these figures, the system uses a defect detection system 101, an abrasive water jet nozzle device 102, and a supply system 103 for supplying high-pressure water and abrasive to the nozzle. And a recovery processing system 104 for recovering the recycled abrasive and supplying it to the supply system 103 again.

Information from each of these systems is input to the grinding control device 105, and the input information is controlled by the judgment function of the grinding control device 105. Is configured.

The slab W to be processed is processed through three stages: an inspection stage S1, a grinding stage S2, and an inspection stage S3. Inspection stage S 1 and inspection stage S 3 Either may be omitted.

The defect detection system system 101 includes a defect detection system system 111 for detecting defects on the slab surface before grinding, a defect detection system system 112 for detecting the state of surface defects during the grinding process, and It has a defect detection system system 113 that detects defects on the slab surface after grinding for the next process, detects the state of surface defects at each stage, and uses that information as a grinding control device 105 And the power is controlled by the variation of the abrasive water nozzle unit 102 and the supply system 103.

Abrasive water jet nozzle device 102 is controlled by a nozzle drive control device 106 and a nozzle drive device 107 controlled by a grinding control device 105. It consists of a driven nozzle 108.

FIGS. 13 to 16 are diagrams showing the specific arrangement of the system shown in FIG.

A supply system 103 composed of a high-pressure water generator 31 for supplying high-pressure water to the nozzle and an abrasive supply device 32 shown in FIG. 12 is provided. The slab is composed of a nozzle device 122 and a nozzle device 122 for grinding the lower surface of the slab turned by the reversing device 42. Each of the nozzle devices 122, 122 has three nozzles 108 arranged in the longitudinal direction of the steel plate slab W produced by the continuous forming machine 41, respectively. Each nozzle 108 is located on the base 1 2 3 that straddles the slab moving floor 109. It is attached to the tip of a 6-axis robot 125 provided on the guide 124, and each nozzle 108 has a nozzle drive controller 106 and a nozzle shown in Fig. 12 The driving is controlled by the driving device 107.

The driving device of this nozzle 108 is a robot,

An NC device can be used, and the robot can be an articulated robot that is mounted on the ground or suspended from the ceiling, mounted on a wall, or used in combination with one or more robots. Multiple units can be used. Further, the driving device may be fixed, or may be driven on one or more axes as shown in this figure. The abrasive nozzle head may be a direct injection method (a method in which abrasive and water are mixed in advance at a high pressure and the slurry is sprayed from the nozzle portion in a high pressure state). Various modes can be adopted as the method of operating the shake, such as various combinations of rotational swinging motions.

According to the invention of this application, non-contact and automatic grinding can be performed by jetting a high-pressure water jet mixed with an abrasive onto a steel slab. In a harsh working environment with noise and heat due to the use of means for removing defects and scratches by manually performing scarfing (melting) and grinding wheels. Significant improvement (unmanned, etc.) is possible, and in addition, harmful defects and defects existing on or near the surface of the slab can be stably and reliably removed, and there is no melting or thermal deterioration of the material. An excellent effect that can be removed at a required depth is obtained without accompanying. Circulate the abrasive if necessary The combined use of the ring utilization system enables continuous work without deteriorating the function of the abrasive water jet itself, leading to an excellent system that leads to resource saving and cost down. System can be provided.

In addition, the need for removing defects and scratches on the surface of billets has been increasing in recent years along with the demand for higher performance of materials, and the invention of this application is a very useful manufacturing method. An excellent effect of being able to provide processing means is achieved.

Claims

The scope of the claims

1. In the method of grinding abrasive slabs by projecting abrasives from the nozzle onto the slab during or after the continuous manufacturing process, high-pressure water mixed with fine-grained abrasives is applied to the surface of the slabs. A grinding method characterized by projecting as an edge and grinding at least a flaw on the surface and in the vicinity thereof.

2. The grinding method according to claim 1, wherein, in the grinding method using the above-mentioned jig during or after a continuous manufacturing process, a portion where a defect is present is finished to be substantially smooth.

3.0 the abrasive. 5 kgZmin along with supplying at least the pressure 1 0 0 O kg f Zcm ² or more, the flow rate S ^ Zmin supplying high-pressure water on more than, high pressure these abrasive and high pressure water By mixing in advance in the nozzle head or by mixing in the nozzle head after jetting high-pressure water, high-pressure water mixed with abrasive is formed, and the projection angle ( Under conditions where the impact angle is between 10 ° and 170 ° and the injection distance between the nozzle and the billet is within 200 mm, the steel is projected onto the billet surface and ground. The grinding method according to any one of claims 1 and 2, characterized in that:

4. In a method of projecting an abrasive material from a nozzle onto a steel slab in a continuous manufacturing process or a subsequent process to grind the steel slab, the method automatically detects the steel slab and a defect near the surface thereof, Before, after and / or at least one of the detections, high-pressure water mixed with fine-grained abrasive is jetted onto the surface of the slab and jetted onto the surface of the steel slab. A grinding method characterized by grinding flaws.

5. In the method of grinding abrasive slab by projecting abrasives from the nozzle onto the steel slab during or after the continuous manufacturing process, the whole surface or part of the slab is detected and the coordinates are transformed. A grinding method comprising: a grinding surface determination system; and a driving method for driving and moving a high pressure fluid nozzle for abrasive injection based on information converted in coordinates by the grinding surface determination system.

6. A grinding system for the surface of a base material using an abrasive water jet, which is an abrasive supply system that supplies the abrasive and a grinding nozzle that has a nozzle that moves relative to the base material. A grinding system comprising: an apparatus system; and an abrasive recovery system that collects the abrasive after the grinding process and returns the abrasive to a supply system of the abrasive.

7. This is a grinding system for the surface of the base material by abrasive jets, based on a defect detection system that detects flaws on the base material surface and flaw information detected from the flaw detection system. A grinding control system that transmits controlled grinding conditions, a polishing material supply system that controls the supply of abrasives based on signals from the grinding control system, and a base material relative to the base material based on signals from the grinding control system. A grinding system having a grinding nozzle device system provided with a moving nozzle.

8. This is a system for grinding the surface of a base material by means of an abrasive water jet. A defect detection system, a grinding control system that transmits controlled grinding conditions based on flaw information detected from the defect detection system, and an abrasive material that controls the supply of abrasive material based on signals from the grinding control system A supply system, a grinding nozzle device system provided with a nozzle that moves relatively to the base material based on a signal from the grinding control system, and an abrasive material after the polishing process is collected and supplied to the abrasive material supply system. Return A grinding system consisting of an abrasive recovery system.