TWM570316U - Tap hole drill bit for blast furnace - Google Patents

Abstract

A tapping bit for a blast furnace comprising a bit body and a plurality of cutting edges. The radius of the bit body is gradually reduced from the front end to the rear end, and includes a plurality of inlaid portions angularly spaced around an axis and each having a maximum radius, and an axial channel extending along the axis. Each inlay has a front end face. The front face is defined by two parallel sides that are parallel to the maximum radius and that are located on either side of the maximum radius. Each of the inlaid portions further has two side bevels extending obliquely rearward from the parallel sides of the front end face. The cutting edges are respectively disposed on the front end faces of the inlaid portions of the bit body. Each inset of the bit body defines two oblique channels that extend from the side bevels to the axial channel. The exit of each pair of diagonal channels is adjacent to the corresponding cutting edge.

Description

Blast furnace drill bit

The present invention relates to a drill bit, and more particularly to a tap hole drill bit for a blast furnace.

Referring to Figure 1, the steel plant using the blast furnace equipment for molten iron smelting is based on the diameter of the blast furnace hearth, and two to four tapholes 11 are opened in the hearth 10 of the blast furnace (Fig. 1 shows only one tap hole 11). ). A tapping machine 12 is disposed in front of the tap hole 11 to perform the opening operation, so that the molten iron inside the blast furnace bed 10 can be guided and discharged, so that it can flow into the main channel and then use the torpedo car ( The figure does not show) carrying molten iron to the downstream.

Usually, the tapping operation of one tap 11 will last for two to three hours. After most of the molten iron in the blast furnace is discharged, the mud blocking material (not shown) is used to block the mud material into the tap hole 11 to close the passage. The plugged mud material is mainly composed of heat-resistant material. After a period of high temperature calcination, the hardness will gradually increase, so that the taphole 11 can be solidly blocked, and the blast furnace can continue to generate and store molten iron until the next time. Open the hole. In this way, all the tapping ports 11 take turns to perform the opening-blocking operation in this mode.

In the above-mentioned opening operation, the drill bit 13 of the tapping machine 12 is rotated and impacted, and the drill bit 14 is cut or impacted into a granular shape by the drill bit 14 at the front end of the drill pipe 13. In the process, in order to avoid the strength of the drill bit 14 from being lowered due to the high temperature generated by the friction, nitrogen gas and cooling water are usually used in combination, and water vapor is allowed to pass through the drill pipe 13 and ejected from the front end of the drill bit 14 to achieve a cooling effect. At the same time, the powder-like plugged material is blown and discharged by the moisture, thereby drilling the tap hole 11.

Referring to Figures 2 through 4, a conventional drill bit 21 is welded to a drill pipe 22. The drill bit 21 includes a drill body 23 and three blade blocks 20 that are inlaid and fixed to the front end of the drill body 23. The diameter of the bit body 23 is gradually reduced from the front end to the rear end of the bit body 23, and the rear end is combined with the front end of the drill pipe 22. The bit body 23 has three inlaid portions 231 spaced apart from each other, an axial channel 230, and three oblique channels 232 communicating with the axis channel 230. As shown in FIG. 4, the recesses where the two adjacent inlaid portions 231 meet define a side groove 233. Each of the oblique passages 232 is located between the two inlaid portions 231 and communicates with the corresponding side grooves 233. Each of the blade blocks 20 is coupled to the front end surface of the corresponding inlaid portion 231 of the bit body 23.

When the drilling operation is performed, the drill bit 21 is rotated and slowly advanced, and the blade block 20 can be used to cut the mud block in the tap hole. At the same time, the nitrogen gas and the cooling water are introduced into the drill pipe 22 to enter the axial passage 230 of the drill bit 21, and then blow out from the oblique passage 232 and the front end outlet of the axial passage 230 to cut the powder. The particles are blown and driven out of the hole until the internal molten iron flows out through the drilling, that is, the opening of the tap hole is completed.

However, the strength of the sintered cement will increase sharply as the depth of the opening becomes deeper. In addition, since the temperature is higher as the inside of the hearth is higher, and the drill bit 21 generates high heat due to the rotational friction, the strength of the bit body 23 and the blade blocks 20 is weakened and becomes easy to wear, resulting in a drilling feed speed. The drastic slowdown forced the hole opening mode of the impact (ie, the ram) to be completed. The impact action will have a rather adverse effect on the carbon bricks near the taphole, such as the permanent damage of the internal carbon bricks forming cracks. Therefore, in general, the drill pipe 22 is filled with nitrogen gas and cooling water, which has the effect of cooling the drill bit 21 in addition to the powder particles that can be blown.

Unfortunately, when the cooling effect of the drill bit 21 is not good, that is, when it is too late to take away the heat, the drill bit 21 is caused to accumulate heat and is easily worn, resulting in a slow feed rate. At this time, the hammer must be started frequently. Therefore, the internal cracking of the carbon brick is further serious, and the service life of the blast furnace will be shortened eventually. Therefore, it is necessary to seek a solution.

Therefore, the object of the present invention is to provide a tap hole drill for a blast furnace.

Therefore, the new blast furnace tap hole drill has a rear end coupled to a drill pipe and is suitable for the opening operation of the blast furnace, and includes a drill body and a plurality of cutting edges. The radius of the bit body is gradually reduced from the front end to the rear end, and includes a plurality of inlaid portions angularly spaced around an axis and each having a maximum radius, and an axial passage extending along the axis. Each inlay has a front end face. The front face is defined by two parallel sides that are parallel to the maximum radius and that are located on either side of the maximum radius. Each of the inlaid portions further has two side bevels extending obliquely rearward from the parallel sides of the front end face. The cutting edges are respectively disposed on the front end faces of the inlaid portions of the bit body. Each inset of the bit body defines two oblique channels that extend from the side bevels to the axial channel. Wherein, the exit of each pair of oblique channels is adjacent to the corresponding cutting edge.

The effect of the present invention is that each of the inlaid portions of the bit body defines two oblique passages respectively extending from the side slopes to the axial passage, and the outlets of each pair of oblique passages are adjacent to the corresponding The cutting edge can shorten the heat transfer distance to accelerate the heat removal of the bit body and provide better cooling efficiency to ensure the inlay of the bit body and the strength and hardness of the blade. The drilling feed rate is maintained to reduce the time required to activate the ram, thereby avoiding the cracking of the carbon bricks and thereby prolonging the service life of the blast furnace.

Referring to Figures 5, 6, and 7, an embodiment of the tapping bit 3 for a blast furnace of the present invention has a rear end coupled to a drill pipe (not shown) and is suitable for the opening operation of a blast furnace (not shown), and A bit body 31 and a plurality of cutting edges 32 are included. As shown, in the present embodiment, the number of the blades 32 is three.

As shown in FIGS. 5 and 7, the radius of the bit body 31 is gradually reduced from the front end to the rear end, and is generally conical in appearance, and includes a plurality of angularly spaced intervals around an axis 30 and each having a maximum radius. The inlaid portion 311 of the R, and a shaft center passage 312 extending along the axis 30. In this embodiment, the number of the inlaid portions 311 is the same as the number of the cutting edges 32, that is, three, and the inlaid portions 311 are arranged at equal angles around the axis 30, that is, It is said that the angle between each two inlaid portions 311 is 120 degrees. In addition, as shown in FIG. 7, in the present embodiment, the recessed portion where the two adjacent inlaid portions 311 of the bit body 31 intersect define a side groove 314.

Each of the inlaid portions 311 has a front end face 3111. In this embodiment, each front end face 3111 is defined by two parallel side edges 3112 that are parallel to the corresponding maximum radius R and are located on both sides of the maximum radius R, wherein each inlay portion 311 has two Side slopes 3113 extending obliquely rearward from the parallel sides 3112, respectively.

In the embodiment, the cutting edges 32 are respectively disposed on the front end face 3111 of the insert portion 311 of the bit body 31.

Each inlaid portion 311 of the bit body 31 defines two oblique channels 313 respectively extending from the side bevels 3113 to the axial channel 312, wherein each of the oblique channels 313 has a connection with the axis channel 312 The inlet 3130 and the outlet 3131 are as shown in FIG. 6. That is, as shown in FIG. 7, in the present embodiment, in the case where the number of the inlaid portions 311 and the number of the cutting edges 32 are three, the number of the oblique channels 313 is three pairs (also That is six), and the outlets 3131 of each pair of diagonal channels 313 are adjacent to the corresponding cutting edge 32.

In the present embodiment, since the outlets 3131 of each pair of oblique passages 313 are adjacent to the corresponding cutting edges 32, the heat transfer distance can be shortened to accelerate the heat absorption of the bit body 31 (including friction and heat generation). And the environmental heat transfer, so that a better cooling efficiency can be provided to ensure the strength and hardness of the inlay portion 311 of the bit body 31 and the cutting edges 32, so that the drilling feed rate can be maintained to reduce When the ram is activated, the cracking of the carbon brick can be avoided, thereby achieving the effect of prolonging the service life of the blast furnace. In the present embodiment, the actual test, the new blast furnace tap hole drill 3 can reduce the use time of the ram is about 10% to 20%, so the present invention can certainly produce the required effect.

In addition, it should be particularly noted that although the number of the inlaid portions 311 and the number of the cutting edges 32 are both three in the above embodiment, the present invention is not limited thereto, but in other embodiments of the present invention, The number of the inlaid portions 311 and the number of the cutting edges 32 may be two, four, or four or more, and the effects of the present invention can also be achieved.

In summary, each of the inlaid portions 311 of the bit body 31 of the present invention defines two oblique channels 313 extending from the side bevels 3113 to the axial channel 312, and each pair of oblique channels 313 The outlets 3131 are adjacent to the corresponding cutting edges 32, so that the heat transfer distance can be shortened to speed up the heat removal of the bit body 31 and provide better cooling efficiency to ensure the inlay of the bit body 31. The strength and hardness of the portion 311 and the blades 32 are such that the drilling feed rate is maintained to reduce the time required to activate the ram, thereby avoiding the cracking of the carbon bricks and thereby prolonging the service life of the blast furnace. This novelty can indeed achieve the purpose of the novel.

However, the above is only the embodiment of the present invention, and when it is not possible to limit the scope of the present invention, all the simple equivalent changes and modifications according to the scope of the patent application and the contents of the patent specification are still This new patent covers the scope.

3‧‧‧Burning drill bit for blast furnace

30‧‧‧Axis

31‧‧‧ bit body

311‧‧‧Inlay Department

3111‧‧‧ front end

3112‧‧‧ parallel sides

3113‧‧‧ Side slope

312‧‧‧ Axis channel

313‧‧‧ diagonal channel

3130‧‧‧ Entrance

3131‧‧ Export

314‧‧‧ side groove

32‧‧‧blade

R‧‧‧Max radius

Other features and effects of the present invention will be apparent from the following description of the drawings, wherein: Figure 1 is a side elevational view showing that a tapping machine is provided in front of the taphole of the hearth of the blast furnace to perform Fig. 2 is a cross-sectional view showing a drill bit and a drill pipe of a conventional hole punching machine; Fig. 3 is a perspective view showing the drill bit of Fig. 2; Fig. 4 is a plan view showing the drill bit of Fig. 2; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 6 is a perspective cross-sectional view showing the embodiment; and FIG. 7 is a plan view showing the embodiment.

Claims (7)

A tapping bit for a blast furnace, the rear end of which is coupled to a drill pipe and is suitable for the opening operation of the blast furnace, and comprises: a bit body whose radius is gradually reduced from the front end to the rear end, and includes a plurality of surrounding An axially spaced apart portion and each having a maximum radius of the inlaid portion, and an axial passage extending along the axis, each inlaid portion having a front end face, the front end face being two parallel to the a maximum radius and defined by parallel sides on either side of the maximum radius, wherein each inset has two side bevels extending obliquely rearward from the parallel sides of the front face; and a plurality of blades And respectively disposed on the front end surface of the insert portion of the bit body; wherein each inlay portion of the bit body defines two oblique passages respectively extending from the side slopes to the shaft center passage, wherein each The exit to the diagonal channel is adjacent to the corresponding cutting edge. The tap hole drill bit for a blast furnace according to claim 1, wherein the bit body has a tapered cylindrical shape. The tapping bit for a blast furnace according to claim 1, wherein the number of the inlaid portions of the bit body is three, and the number of the blades is also three. The tapping bit for a blast furnace according to claim 1, wherein the number of the inlaid portions of the bit body is two, and the number of the blades is also two. The tapping bit for a blast furnace according to claim 1, wherein the number of the inlaid portions of the bit body is four, and the number of the blades is also four. The tapping bit for a blast furnace according to claim 1, wherein the inlaid portions of the bit body are arranged at equal angular intervals around the axis. The tapping bit for a blast furnace according to claim 1, wherein the recess of the two adjacent inlaid portions of the bit body defines a side groove.