Add:no.8 liaohe road, Liaocheng city, Shandong Province. China
drill rod 38x12mm blast furnace tap hole drill rod
The invention relates to a drilling tool, namely the bits for rotary percussive drilling, used mainly in the steel industry for opening notches for blast furnaces.
Famous crown for rotary percussive drilling comprising a shank and a working cylinder, divided in the front-end part on the feathers, reinforced carbide inserts (SU 1430495 And class. EW 10/36, 1988).
A disadvantage of the known crown is a high probability of failure during operation due to loss of inserts from the housing crowns because of unreliable fix them, as well as the necessity of regrinding of the tool wear of the inserts.
Famous crown for rotary percussive drilling, containing made solid shank and a working cylinder, divided into the mechanical part of the cross Ruseckas on solid shank working pens, made with polaroiding active surface, followed by a truncated cone, with the working head has a Central flushing channel connected to rasejcami, turning in his pockets to remove stuff (EN 2201490 C1, CL EV 10/36, 27.03.2003).
The known device is devoid of the disadvantages associated with the presence of carbide inserts, however, is not a high performance and service life, due to the fact that atrustee breed feathers is due to strike.
Famous crown for rotary percussive drilling, the casing of which is a monolithic adenostyletum and the working surface is made in the form of a body of rotation about the axis of symmetry of the crown and separated at the periphery of the feathers in the form of a Maltese cross and has pockets for removal of products of drilling with casing made of two lateral flushing holes connected to the Central channel (RU 2202029 C2, CL EV 10/36, 10.04.2003).
In this arrangement, the shock is perceived massive Central part of the head - rock pin, allowing the shock load, which is the destruction of the breed due to the rotation of the crown. Thus, the absence of shock loads on the feathers increases their service life. However, this is achieved by reducing the effectiveness of the crown as a whole. This known device is not suitable for use in the metallurgical industry, in particular, for opening notches for blast furnaces.
Closest to describing the crown to the technical essence and the achieved result is a crown for rotary percussive drilling, used in the metallurgical industry and contains a rod with the destructive element made in the form of planted at the end of the rod or cross trecherous head chisel t is PA, the rod is made with a through axial channel and side channels for the supply of coolant to the head (EN 38760 U1, CL SW 7/12, 2004).
The disadvantage of the closest analogue is the relatively low durability of its destructive element - head due to increased wear of the cutting edge due to the accumulation of drilling detail in the zone of destruction of the breed. This leads to additional consumption of the instrument. In addition, due to non-optimal sharpening of the cutting edges increased the duration of the operation of opening the tap hole, which leads to increase the time of release of iron from the furnace.
The objective of the invention is to develop crowns for rotary percussive drilling, free from the above disadvantages nearest analogue, and therefore, the technical result provided by the invention is to increase the service life of the head, as a destructive element, as well as reducing the duration of opening the tap hole.
This result is achieved in that in the crown for rotary percussive drilling, primarily for opening notches for blast furnaces, containing the bar with the destructive element made in the form of planted at the end of the rod or cross trecherous head chisel type, and the rod is made with a through axial channel and side channels for the supply of coolant to the cylinder, m is waiting for the cutting teeth of the cutting element is made oblique grooves, and the teeth of the cutting element is made with a cutting angle 125-130°.
In addition, the depth of the grooves may be 5-11 mm, and a width of 7-12 mm
The invention is illustrated in the accompanying drawings, in which figure 1 shows a General view of the crown, figure 2 is a view As in figure 1 and figure 3 - cross section b-b In figure 2.
Crown for opening notches for blast furnaces consists of a body 1, at one end of the shank 2 threaded for connection with the drill, and at the other end planted crosswise or trempera head 3 with three flushing holes 4 and the cutting elements with the teeth 5, between which is made oblique grooves 6.
When the crown for opening notches for blast furnaces is the destruction of the tap weight of the Central part of the crown due to the strike. The clean channel from the destroyed products is carried out with compressed air or a cooled inert gas flowing through the flushing holes 4. Remove the drill little things provide grooves 6.
The design of the working parts of the crown helps preserve the original shape when worn as an active part of the crown, destroying the breed has a large area and slightly worn, and the peripheral part has a margin for wear. Therefore, the crown has the effect of sharpening. Increased the height of the working teeth determines their stock for wear and, after vetelino, increased operating life of the tool. The presence of the crown as a whole forms the rock-pin allows for increased shock load.
To determine the optimal dimensions of the slots were made of the party of crowns with different sizes of slots that have been tested for blast furnace No. 3 at JSC "Tulachermet". The results are shown in the table, which shows that the optimal dimensions of the groove for a crown diameter of 65 mm are: width is 10 mm and the depth is 7 mm, the dimensions of the groove more than the above, lead to structural weakening of the tooth and premature failure. When reducing the size of the groove there is a decrease in drilling efficiency (increasing the time of opening the tap hole) or the failure of the crown-rod due to rolling of the cutting edge.
Also it is found experimentally that the optimum sharpening angle of the tooth crowns is 125-130°that is especially true for steel crowns (without hard alloy). When sharpening angles less than 125° is the rolling of the cutting edges of the teeth when the blows of a hammer, which increases the consumption of the instrument and increases the duration of the operation of cutting notches, and at angles greater than 130°occurs breakage of the teeth of the cutting elements and reduces the efficiency of crowns due to the increase of the length of the cutting notches.
Izaberete the ie is not limited to the above formula the purpose, and may find application in other industries, such as mining, drilling rocks low strength.
|The size of groove (mm)||The grinding angle, °||The time of opening the tap hole (min.) or the reason for failure of crowns|
|3||5||110||Rolling cutting edge|
|5||5||110||Rolling cutting edge|
|7||5||120||Rolling cutting edge|
|3||7||120||Rolling cutting edge|
|5||7||120||Rolling cutting edge|
|3||10||120||Zavalis the WHC cutting edge|
|9||10||130||Breakdown 1 tooth|
|11||10||133||Breakdown 1 tooth|
|3||12||120||Rolling cutting edge|
|5||12||120||Rolling cutting edge|
|9||12||130||Breakdown 2 teeth|
|11||12||130||Breakdown 2 teeth|
|3||15||120||Rolling cutting edge|
|5||15||120||Rolling cutting edge|
|7||15||120||Breakdown 1 tooth|
|9||15||120||Breakdown 2 teeth|
|11||15||120||Breakdown 4 teeth|
1. Crown for rotary percussive drilling, primarily for opening the tap hole of the blast furnace, containing the bar with the destructive element executed is output in the form of planted at the end of the rod or cross trecherous head chisel-type cutting elements with teeth, the rod is made with a through axial channel and side channels for the supply of coolant to the cylinder, characterized in that between the teeth of the cutting element is made oblique grooves, the teeth are made with a cutting angle 125-130°.
2. Crown according to claim 1, characterized in that the depth of the grooves is 5-11 mm, and the width of 7-12 mm
NEWS CENTER / QiYan Metal