Sealing structure for hydraulic rock drill

Abstract

The utility model belongs to the field of hydraulic rock drills, and particularly relates to a sealing structure for a hydraulic rock drill, which comprises a machine head, a bit shank arranged in the machine head, a water injection hole arranged in the machine head, and a bit shank water injection hole arranged at the corresponding position of the bit shank and the machine head water injection hole. A first sealing groove and a second sealing groove which are of an annular structure are symmetrically formed in the positions, located on the two sides of the machine head water injection hole, of the inner wall of the machine head, a third sealing groove of an annular structure is formed in the position, located on one side of the second sealing groove and away from one side of the first sealing groove, of the inner wall of the machine head, and step seal rings are arranged in the first sealing groove and the second sealing groove correspondingly. A U-shaped sealing ring is arranged in the third sealing groove, and the third sealing groove is in interference fit with the bit shank during working; the sealing device is simple in structure, convenient to manufacture and good in sealing performance.

Description

Technical Field

[0001] The utility model belongs to the field of hydraulic rock drills, and in particular relates to a sealing structure for a hydraulic rock drill. Background Art

[0002] Hydraulic rock drills have the advantages of fast drilling speed, high drilling efficiency and high energy utilization, and are widely used in mining, construction projects, tunnel excavation and other occasions.

[0003] like Figure 1 and 2 As shown, the existing hydraulic rock drill uses a U-shaped sealing ring for sealing between the drill bit and the drill head. From the perspective of the sealing mechanism, the U-shaped sealing ring has poor wear resistance for reciprocating linear motion and rotational motion, which easily leads to wear and leakage. However, the drill bit performs a spiral motion that is a combination of reciprocating linear motion and rotational motion during operation. Therefore, the U-shaped sealing ring is not suitable for use in such working conditions. As a result, its life is short and it needs to be replaced frequently, which reduces the working efficiency of the hydraulic rock drill.

[0004] For example, the Chinese patent with patent publication number CN202531835U discloses a shank sealing device for a hydraulic rock drill. A rotating grid ring is used at the flushing head inside the hydraulic rock drill head. The rotating grid ring consists of a sealing ring and an O-ring. The sealing ring of the rotating grid ring and the mounting surface of the shank are processed with parallel rectangular grooves with a rectangular cross-section, and the mounting surfaces of the sealing ring and the O-ring are concave.

[0005] Although the above-mentioned sealing device meets the requirements of the shank movement conditions to a certain extent and improves the service life, the sealing device still has some shortcomings. First, the rectangular groove and the concave shape of the sealing ring and the shank mounting surface are subject to strict processing accuracy, which increases the manufacturing difficulty and cost, reduces production efficiency, and the processing deviation will directly affect the sealing effect; second, the rectangular groove is prone to accumulate impurities such as dust and rock chips, which have a negative impact on the sealing performance and reduce the sealing reliability; third, although the rotating grid ring can theoretically adapt to the shank movement conditions, in actual work, due to the complex and changeable forces in different movement states, the sealing ring and the shank may not fit tightly, increasing the risk of leakage. Utility Model Content

[0006] The main technical problem to be solved by the utility model is to provide a sealing structure for a hydraulic rock drill which has a simple structure, is easy to manufacture and has good sealing performance.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] A sealing structure for a hydraulic rock drill comprises a machine head, a drill tail being arranged in the machine head, the drill tail rotating and reciprocating in the machine head, a water injection hole being provided in the machine head, a drill tail water injection hole being penetrated through the drill tail at a position corresponding to the machine head water injection hole, a first sealing groove and a second sealing groove being symmetrically arranged in an annular structure on the inner wall of the machine head on both sides of the machine head water injection hole, a third sealing groove being in an annular structure being arranged on the inner wall of the machine head on one side of the second sealing groove and away from the first sealing groove, step seal rings being provided in both the first sealing groove and the second sealing groove, and being sleeved on the drill tail with an interference fit with the drill tail, a U-shaped sealing ring being provided in the third sealing groove, and being sleeved on the drill tail with an interference fit with the drill tail.

[0009] The following is a further optimization of the above technical solution by the present invention:

[0010] The step seal ring comprises a slip ring with a trapezoidal structure, and the slip ring is sleeved on the shank and has an interference fit with the shank.

[0011] Further optimization: an O-ring is tightly fitted on the outer side of the slip ring.

[0012] Further optimization: the slip ring is made of polytetrafluoroethylene filled with molybdenum disulfide and bronze powder.

[0013] The utility model can effectively prevent the flushing liquid at the water injection hole of the machine head and the water injection hole of the drill tail from entering the front end of the machine head and causing poor lubrication and wear of the guide sleeve through the Step seal in the second sealing groove and the U-shaped sealing ring in the third sealing groove, which can effectively prevent the flushing liquid and its impurities from entering the interior of the rock drill rigid body from the rear end of the machine head and affecting the normal operation of the rock drill.

[0014] By adopting the above technical solution, the utility model has a simple structure, is easy to manufacture and has good sealing performance.

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the overall structure of the sealing structure of the background technology of the embodiment of the present utility model;

[0017] Figure 2 This is a schematic diagram of the sealing structure of the background technology of the embodiment of the present utility model;

[0018] Figure 3 This is a schematic diagram of the overall structure of an embodiment of the present utility model;

[0019] Figure 4 It is a partial structural diagram of an embodiment of the present utility model.

[0020] In the figure: 1-machine head; 2-shank; 3-machine head water injection hole; 4-shank tail water injection hole; 5-first sealing groove; 6-second sealing groove; 7-third sealing groove; 8-step seal ring; 81-slip ring; 82-O-ring; 9-U-ring. DETAILED DESCRIPTION

[0021] like Figure 3-4 As shown, a sealing structure for a hydraulic rock drill comprises a machine head 1, a drill tail 2 is provided in the machine head 1, the drill tail 2 rotates and reciprocates in the machine head 1, a machine head water injection hole 3 is penetrated on the machine head 1, a drill tail water injection hole 4 is penetrated on the drill tail 2 at a position corresponding to the machine head water injection hole 3, a first sealing groove 5 and a second sealing groove 6 with an annular structure are symmetrically provided on the inner wall of the machine head 1 on both sides of the machine head water injection hole 3, a third sealing groove 7 with an annular structure is provided on the inner wall of the machine head 1 on one side of the second sealing groove 6 and away from the first sealing groove 5, step seal rings 8 are provided in both the first sealing groove 5 and the second sealing groove 6, and are sleeved on the drill tail 2 with an interference fit with the drill tail 2, a U-shaped sealing ring 9 is provided in the third sealing groove 7, and is sleeved on the drill tail 2 with an interference fit with the drill tail 2.

[0022] With this design, first of all, not only can the step seal ring 8 in the first sealing groove 5 effectively prevent the flushing liquid at the head water injection hole 3 and the drill tail water injection hole 4 from entering the front end of the head 1 and causing poor lubrication and wear of the guide sleeve; but also the double seal of the step seal in the second sealing groove 6 and the U-shaped sealing ring 9 in the third sealing groove 7 can effectively prevent the flushing liquid and impurities thereof from entering the interior of the rock drill rigid body from the rear end of the head 1 and thus affecting the normal operation of the rock drill.

[0023] Secondly, the symmetrically designed step seal ring 8 balances the internal pressure of the machine head 1, reduces the risk of seal failure, and improves the overall stability; and the interference fit makes the sealing structure firm and does not loosen under strong vibration and impact, ensuring the reliability of the seal, maintaining good performance even in harsh environments, and extending the life of the equipment.

[0024] Thirdly, the step seal ring 8 has a low friction coefficient, which reduces friction loss, makes the drill tail 2 move more smoothly, reduces movement resistance and heat generation, and extends the life of the seal and the drill tail 2; at the same time, the good sealing structure also improves the rock drilling accuracy and quality, reduces working instability factors, and improves operating performance and control accuracy.

[0025] The step seal ring 8 includes a slip ring 81 with a trapezoidal structure, and the slip ring 81 is sleeved on the shank 2 and has an interference fit with the shank 2 .

[0026] With this design, the trapezoidal slip ring 81 has an interference fit with the drill tail 2, so that the slip ring 81 and the drill tail 2 are highly tightly fitted, thereby effectively preventing the flushing liquid from flowing out from both sides of the machine head water injection hole 3 and the drill tail water injection hole 4. This not only effectively prevents the flushing liquid at the machine head water injection hole 3 and the drill tail water injection hole 4 from entering the front end of the machine head 1 and causing poor lubrication and wear of the guide sleeve, but also effectively prevents the flushing liquid and impurities thereof from entering the interior of the rock drill rigid body from the rear end of the machine head 1, thereby affecting the normal operation of the rock drill.

[0027] An O-ring 82 is tightly fitted on the outer side of the slip ring 81 .

[0028] First, the good elasticity of the O-ring 82 can adapt to the slight shape and size changes between the slip ring 81 and the head 1 and the drill tail 2 caused by vibration and temperature changes during the operation of the rock drill, automatically adjust the sealing state, and maintain a good sealing effect.

[0029] Secondly, the interlocking elasticity of the O-ring 82 enables the slip ring 81 to fit tightly against the drill tail 2, reducing the risk of seal failure, extending the life of the seal and improving equipment reliability. It can also absorb vibration and impact, protect the integrity of the sealing structure, and ensure stable operation of the rock drill in harsh environments.

[0030] The slip ring 81 is made of polytetrafluoroethylene filled with molybdenum disulfide and bronze powder.

[0031] With this design, first, molybdenum disulfide reduces the friction coefficient of the slip ring 81, reduces movement resistance, makes the drill tail 2 move more smoothly, improves the working efficiency of the rock drill, and also reduces frictional heat and the risk of thermal damage; bronze powder improves the adhesion between the slip ring 81 and the metal surface, reduces the probability of adhesive wear, maintains the surface smoothness of the slip ring 81, and improves the sealing performance.

[0032] Secondly, molybdenum disulfide and bronze powder enhance the resistance of the slip ring 81 to corrosive substances in the working fluid, ensuring that the slip ring 81 is not damaged by corrosion during long-term use, maintaining the integrity and reliability of the sealing structure, adapting to harsh working environments such as high temperature, high pressure, and humidity, and providing reliable sealing performance for the hydraulic rock drill.

[0033] Thirdly, bronze powder improves the thermal conductivity of the slip ring 81, can quickly dissipate heat, avoid excessive temperature affecting the sealing performance and service life, reduce the overall temperature of the equipment, improve working stability and reliability, and can also effectively prevent local overheating and balance the temperature distribution.

[0034] For ordinary technicians in this field, based on the teachings of this utility model, without departing from the principles and spirit of this utility model, changes, modifications, substitutions and variations made to the implementation methods are still within the scope of protection of this utility model.

Claims

1. A sealing structure for a hydraulic rock drill, comprising a head (1), a drill tail (2) provided in the head (1), the drill tail (2) rotating and reciprocating in the head (1), a head water injection hole (3) penetrating the head (1), and a drill tail water injection hole (4) penetrating the drill tail (2) at a position corresponding to the head water injection hole (3), characterized in that: A first sealing groove (5) and a second sealing groove (6) having an annular structure are symmetrically arranged on the inner wall of the machine head (1) on both sides of the machine head water injection hole (3); a third sealing groove (7) having an annular structure is opened on the inner wall of the machine head (1) on one side of the second sealing groove (6) and away from the first sealing groove (5); a step seal ring (8) is arranged in both the first sealing groove (5) and the second sealing groove (6), and is sleeved on the shank (2) and has an interference fit with the shank (2); a U-shaped sealing ring (9) is arranged in the third sealing groove (7), and is sleeved on the shank (2) and has an interference fit with the shank (2).

2. A sealing structure for a hydraulic rock drill according to claim 1, characterized in that: The step seal ring (8) comprises a slip ring (81) with a trapezoidal structure, and the slip ring (81) is sleeved on the shank (2) and has an interference fit with the shank (2).

3. A sealing structure for a hydraulic rock drill according to claim 2, characterized in that: An O-ring (82) is tightly fitted on the outside of the slip ring (81).

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