KR200363485Y1 - The high strength cutting bit for blast furnace tap hole - Google Patents

Abstract

The present invention is the body 110 is coupled to the tapping bar, the tip of the body, the blade 120 is formed to protrude in the upper part (on the upper part), the carbide tip 130 is coupled to the blade and fixed, It consists of a central coolant drain hole 150 and the side coolant drain hole 160 for cooling the cemented carbide tip, the side coolant drain hole 160 to be drilled adjacent to the left side of each blade 120, The coolant discharged through the side coolant drain hole 160 flows along the coolant guide groove 170 dug into the left side of the blade 120 to eject the blast furnace while cooling the blade 120 and the carbide tip 130. It is to provide high strength bit for opening of the hole, and the shape of the bit part and tip coupled to the tip of the tapping bar can open the high strength mud material that is different from the prior art efficiently and safely. The shape of the bit is designed to allow the cut mud material to be discharged quickly, and the coolant hole improves the cutting performance and productivity by maintaining the tip performance and strength even in a high temperature environment by appropriately cooling the tip directly. . In addition, the position of the tip is placed in a position away from the center and the angle at the end to improve the machinability significantly to open the hole by drilling without opening the hammer without risking the furnace wall in the conventional working method It has a significant effect on cutting efficiency, workability and safety.

Description

High strength cutting bit for blast furnace tap hole}

The present invention relates to a bit for opening a furnace outlet, and more particularly to a high strength bit for opening a furnace outlet that can improve the productivity of work through excellent cutting performance, reduction of working time, improvement of workability, safety and the like.

In general, the bit opening for the opening of the furnace is to open a high-strength mud material by mounting it on the tapping bar of the opening of the furnace, and is a very important facility related to the chartering of the steelworks blast furnace.

That is, the furnace (A) for producing iron in steel mill is composed of refractory bricks and various refractory materials to withstand high temperature heat of 1500 ℃ or more and contain molten iron. During the reduction reaction to make molten iron, the molten iron accumulated at the bottom of the furnace should be periodically removed.

Therefore, tapping hole tap (D) is made and used. The tapping hole is filled with a refractory mud material (E), blocked and excavated with an opening machine (B) equipped with a tapping bar (C) and then opened. The charterers will be hired. Opening for the starting line should be carried out several times a day. The mud material is a material that maintains compressive strength and hardness even at high temperature, so in order to excavate it, a carbide tip (Tip) is attached to the tip of the tapping bar.

However, the body 10, the blade 20 is formed to protrude to the front end of the body, the carbide tip 30 is coupled to the fixed blade and the cooling water drain holes 40, 50 for cooling the carbide tip Bits (1) consisting of the recent use of high-strength mud material to improve the productivity of the blast furnace is inevitably weakened, and therefore, two or three bits must be used to open the exit port once, In addition to the increase of working time due to the replacement of these, as well as the safety of workers due to the exposure of waste water and exhaust gas is seriously threatened, the development of higher strength bits is more urgent than ever.

Moreover, with conventional bits, the opening of the exit port is difficult due to drilling alone, and the opening should be carried out while hammering. The hammering impacts the blast furnace, which has the disadvantages such as reduced durability of the equipment and an increase in cost and a decrease in productivity. will be.

Therefore, the present inventors have obtained the following conclusions by analyzing the most advanced high-strength bits to date.

That is, the conventional bit 1 shown in Figs. 1 to 2 has a body 10 made of cast steel (SC), and three blades 20 are formed separately from the front end of the body, and the blade Carbide tip 30 is fixed to the protruded end of each, the cooling water is to have a structure to be discharged between the center of the body 10 and each blade 20 through the tapping bar and the body, the present inventors a number of experiments Through it was confirmed that the cooling effect of the bit (1) is significantly reduced due to the wrong structure of the drain holes (40, 50).

In particular, the side cooling water drain hole 50 in a state that is punctured in the middle of the middle of the blade 20 is disposed around the central cooling water drain hole 40, and because the state is precisely divided by 120 ° angle of about 13kg / ㎠ When is supplied is to be sprayed forward by the instantaneous pressure due to the cooling of the blade 20 and the carbide tip 30 is not injected to the mud material (E).

Therefore, the cooling water ejected through all the cooling water drainage holes together with the central cooling water drainage hole 40 for injecting the cooling water to the mud material (E) is a structure that is not very useful for the direct and direct cooling of the bit body 10. .

Due to this, the carbide tip 30 is overheated, damaged, damaged, or not drilled because the concentricity is not maintained during drilling. This shortens the disadvantage that the departure speed is not constant.

In addition, the conventional bit 1 has a structure in which the cemented carbide tip 30 coupled to the tip of the blade 20 is composed of one cemented carbide tip, so that the area of the cemented carbide tip 30 is closely adhered to the mud material during drilling. The height of the front end face is also the same as the mud material has a disadvantage that can not only increase the amount of heat. In addition, even if the coolant reaches the cemented carbide tip 30, since the volume of the cemented carbide tip is large and it takes a considerable time to cool it all to the center, the cemented tip has a closed end directly causing wear.

The present invention was devised to solve the above problems, and by separating the cemented carbide tips into two, the surface area could be significantly improved, thereby improving cutting performance and cooling performance. Also, the calorific value was improved by improving the height and arrangement of the carbide tips. It is possible to prevent the damage of the furnace by opening the outlet by using only one tapping bar by reducing and improving the cutting force, thereby providing a high strength bit for opening the furnace outlet that can reduce the cost, work time and work safety. It is to.

1-a perspective view of a conventional opening bit for opening.

2-a plan view of a conventional opening bit for opening.

Figure 3-perspective view of a part of the tip in the present invention removed.

Figure 4-perspective view of the tip coupled state in the present invention.

5-4 is a sectional view taken along the line A-A.

6-4 are top views.

Figure 7-perspective view of a part of the tip in a separate embodiment according to the present invention.

8-a perspective view of the tip coupled state in the present invention.

9-8 are sectional views taken along the line B-B.

10-a perspective view of another embodiment of the present invention.

Fig. 11-Reference state of use of the inventive opening opening bit.

* Explanation of Signs of Major Parts of Drawings *

1: conventional opening bit 10: body

20: blade 30: carbide tips

31: tip coupling groove

40: central coolant drain hole 50: side coolant drain hole

100: high strength bit for opening the present invention (hereinafter referred to as opening bit)

110: Body

120: blade 130: carbide tip

131: round tip 132: square tip

140: tip coupling hole (Hole) 141: tip coupling groove

150: central coolant drain hole 160: side coolant drain hole

170: coolant guide groove 180: tapping bar coupling portion

181: cooling water inlet

A: Furnace B: Opening Machine

C: tapping bar D: exit

E: Mud

Referring to the present invention in more detail by the accompanying drawings to achieve the above object is as follows.

First, as shown in FIG. 3, the high-strength bit 100 for opening the furnace outlet of the present invention has a body 110 coupled to a tapping bar, a tip portion of the body, and a blade formed to protrude on an upper portion in the drawing ( 120, a carbide tip 130 coupled to the blade and fixed, and the central coolant drain hole 150 and the side coolant drain hole 160 for cooling the carbide tip, the side coolant drain hole 160 is Perforated adjacent to the left side of each of the blades 120, and the coolant discharged through the side coolant drain hole 160 flows along the coolant guide groove 170 cut into the left side of the blade 120 blades The 120 and the carbide tips 130 are to be sprayed while cooling.

The coolant guide groove 170 is in a state of communicating with the side coolant drain hole 160. At this time, the coolant guide groove 170 formed on the left side of the blade 120 is not limited to the position. In other words, if the direction of rotation of the tapping bar is the right side, of course, the coolant guide groove 170 will be formed on the right side of the blade 120 in the direction of rotation of the tapping bar.

In addition, the end portion of the coolant guide groove 170 is formed to be located between the cemented carbide tip 130 is divided into two at the top of the blade 120, such that the carbide tip 130 is divided into two in general The heat transfer surface area of the conventional cemented carbide tip 30 is only about 6 mm ² because the cooling capacity is significantly lowered to increase the heat transfer surface area to improve this.

Therefore, the coolant injected through the side coolant drain hole 160 moves along the coolant guide groove 170 to cool the blade 120 first, and then flows naturally between the two cemented carbide tips 130 along the rotation of the next bit. Carbide tip 130 will be cooled quickly and directly.

As such, the present invention solves the cooling of the cemented carbide tip 130, which is the most important for opening the high-strength mud material, by separating the cemented carbide tip 130 into two, and allowing the cooling water to pass through the two cemented carbide tips. Could.

In addition, the present invention separates the cemented carbide tip 130 into two, but one side end of the cemented carbide tip 130 is arranged such that the distance is sequentially away from the center of the body 110, the same portion that the previous carbide tip was cut To prevent the next carbide tip from cutting again and again. This is because the position of the conventional carbide tip 30 is the same distance from the center of the bit body, thereby cutting the carbide carbide tips always the same side of the carbide tip rotated earlier. Therefore, the next tungsten carbide tip is cut again and again the portion cut by the previous carbide tip is reduced the cutting effect.

Therefore, the present invention is to fix the carbide tip 130 to the blade 120, but to reduce the contact area with the mud material by varying the height of the cemented carbide tip 130 is divided into two, thereby lowering the heat generation temperature At the same time, the cutting force is distributed to all six carbide tips to maximize cutting capacity.

Also, for the initial drilling, the central carbide tips 131 and 132 are protruded more prominently than the external carbide tips 131a and 132a, but the angle of the tip of the cemented carbide tip is sharpened at a Θ angle, that is, 60 to 70 °, and the central carbide tips The height of the outer carbide tips (131a. 132a) than the tips (131, 132) is formed by about 10 degrees lower to facilitate the cutting of the mud material during excavation, the cut mud material grains were to fall well.

Carbide tip 130 in the present invention can be divided into the case of using only the cylindrical carbide tips (131,131a), and the case of using a cylindrical and rectangular carbide tips (132,132a), the cylindrical carbide tips When only 131 and 131a are used, a cylindrical cemented carbide tip coupling hole 140 is formed at the upper end of the blade 120, and the cemented carbide tips 132 and 132a are inserted thereinto engage.

On the other hand, in the case of using the cylindrical and rectangular carbide tips (132,132a) together to form a cylindrical carbide tip coupling hole 140 on the top of the blade 120 toward the center of the body, the outside of the body of Figure 7 Carbide tip coupling groove 141 as shown in to be formed.

In addition, the present invention gives a slight inclination angle to the side end of the cemented carbide tip located on the outside of the body 110 to prevent the bit body from being caught in the tap hole during drilling, the bit is cut off the mud material, the tap opening port during drilling The wear resistance caused by the wear, or the rotation is not generated, the rotational resistance is generated, the rotational torque is increased and eventually the drilling stops to improve the working obstacles.

The following is a table showing the components and physical properties, cooling quantity, cooling capacity of the mud material component and cemented carbide tips of the high-strength bit 100 of the present invention used in the experiment.

In Table 1 (compare the mud material components) MRC-3 is a conventional mud material and MRC-7-H3 is a high-strength mud material used in the experiment of the present invention.

Carbide tip used in the present invention in Table 2 (mechanical properties of the carbide tip) has a physical property of the E4 type. Finally, in order for the above functions to be performed smoothly, the tips must be sufficiently cooled to maintain strength and the mud material and the coolant should be smoothly discharged.

The cooling water nozzle capacity and cooling water calculation formula considering the bit design and shaping is as follows.

1) Basic condition

Coolant supply pressure: 13 Bar

Bit Nozzle Inlet Diameter: φ20mm

Bit Nozzle Outlet Diameter: φ8mm

Injection pressure per nozzle: 13.26 kg / ㎠

The amount of heat generated at the tip of the bit during opening is shown in the following table.

When comparing total calorific value and cooling calorific value generated at the tip of the bit through Table 3 (cooling amount and cooling calorific value) and Table 4 (calculating calorific value and heat transfer amount), the difference is about 400,000 kcal / hr. It is possible to sufficiently cool the calorific value due to friction at the time of opening and the calorific value of the high temperature heat transmitted from the molten iron so as not to deteriorate the tip. In general, carbide tips maintain the high hardness and strength to maintain sufficient strength to cut the mud material below 600 ° C. The present inventors have obtained theoretical calculations and experimental results that fully support this theory.

Specific test examples of the high strength bits developed based on the above data and calculations are shown in Table 5 below.

As shown in Table 2 (bit test results), the existing bits (1) or Japanese bits have a long cutting time during opening and the tip is worn out completely. It was opened in 5-7 minutes and no impact, but it is successful to open it within 10 minutes at the site. In Japan, 10 ± 5 minutes is the standard opening time.

When the present invention bit 100 is tested on a conventional mud material (MRC-5), only one is opened in two minutes, and the existing bit is opened in ten minutes on average, and there is a difference of several times. It can be seen that this is a much higher strength bit than the existing bit.

In this way, the present invention secures the cutting force by sufficiently cooling the bit and the carbide tip to maintain and improve the cutting force, thereby reducing the working time and the safety of the work by collectively opening it with one tapping bar. Sharpening the angle from 60 to 70 degrees increases the cutting force and reduces the frictional heat.

In addition, the present invention is to open a high-strength mud material through this, resulting in improved productivity and cost savings. It is also a very useful design that can be applied to other places with similar opening conditions.

Claims (8)

Body 110 coupled to the tapping bar, the blade 120 is formed to protrude to the front end of the body, the carbide tip 130 is coupled to and fixed to the blade, and the central coolant drain hole for cooling the carbide tip It consists of a 150 and the side coolant drain hole 160, the side coolant drain hole 160 is to be drilled adjacent to the left side of each blade 120, and discharged through the side coolant drain hole 160 Cooling water flows along the coolant guide groove 170 formed between the blade 120 and the blade flowing high strength bits for opening the furnace outlet, characterized in that configured to be injected while cooling the blade 120 and the carbide tip 130. The high-strength bit for the opening of the furnace opening, characterized in that the carbide tip 130 is separated into two. The high-strength bit for the opening of the furnace, characterized in that the height of the two separated carbide tips 130 are formed differently. The cemented carbide tip 130 of claim 2, wherein the cemented tip 130 close to the center of the bit has a cylindrical shape, and the cemented tip far from the center of the bit has a rectangular shape. beat. According to claim 1, wherein the blade is a high-strength bit for opening the furnace outlet, characterized in that consisting of three to four. The method of claim 1, wherein the coolant guide groove 170 is formed between the blade 120 and the blade, the end portion is formed for opening the blast furnace characterized in that it is formed to be located between the two cemented carbide tips (130) High strength bits. The method of claim 1, wherein the cemented carbide tip 130 is fixed to the blade 120, but one end of the cemented carbide tip 130 is characterized in that the distance from the center of the body 110 in order to be disposed sequentially High-strength bit for opening the furnace exit. According to claim 1, wherein the central carbide tips (131, 132) to protrude more than the outer carbide tips (131a, 132a) to give a sharp angle to the tip of the cemented carbide tip 60 ° ~ 70 °, the central carbide tips High-strength bit for the opening of the furnace outlet, characterized in that the height of the outer carbide tip (131a.132a) is formed 10 ° lower than (131,132).