CN-116044323-B - Drill rod pressurizing block, rotary drilling rig drill rod and preparation method of gradient wear-resistant layer

CN116044323BCN 116044323 BCN116044323 BCN 116044323BCN-116044323-B

Abstract

The invention discloses a drill rod pressurizing block, a drill rod of a rotary drilling rig and a preparation method of a gradient wear-resistant layer, wherein the drill rod pressurizing block is fixed on the outer side surface of a drill rod cylinder and is used for bearing downward pressure of a driving sleeve, the drill rod pressurizing block comprises a base body and the gradient wear-resistant layer fixed at the upper end of the base body, and the upper end profile of the base body is consistent with the lower end profile of the gradient wear-resistant layer; the upper end profile of the gradient wear-resistant layer is a plane, and the gradient wear-resistant layer comprises a coating II with gradually increased radial gradient change of the thickness from the outer side of the drill rod barrel and a coating I with unchanged thickness, wherein the coating I is positioned at the outer side of the coating II. The method has the advantages of solving the technical problem that the abrasion process of the bearing surface of the pressurizing block of the drill rod of the rotary drilling rig is inconsistent due to uneven pressure distribution in the service process, remarkably reducing the depth of a tempering softening area caused by secondary heating in the preparation process through the functionally gradient wear-resistant coating cladding method and path of the ultra-high-speed laser cladding combination, and being capable of accurately positioning the position of the pressurizing block by a special tool, simple in clamping and high in efficiency.

Inventors

ZONG XUEMEI
HE BING
CHANG TONG
WANG JING

Assignees

江苏徐工工程机械研究院有限公司

Dates

Publication Date: 20260505
Application Date: 20230113

Claims (9)

1. The drill rod pressurizing block is fixed on the outer side surface of the drill rod cylinder and is used for bearing downward pressure of the driving sleeve, and is characterized by comprising a base body and a gradient wear-resistant layer fixed at the upper end of the base body, wherein the upper end profile of the base body is consistent with the lower end profile of the gradient wear-resistant layer; the upper end profile of the gradient wear-resistant layer is a plane; the gradient wear-resistant layer comprises a coating II and a coating I, wherein the thickness of the coating II gradually increases from the outer side of the drill rod barrel to the outer side in a radial gradient manner, and the thickness of the coating I is kept unchanged; the thickness of the first coating is H1, the width of the second coating is 2D-2B1, and the gradient thickness H is expressed as H=H2+ (Smax-S)/(Smax-Smin) ×H 2-H1; Wherein, B1 is the width of the area where the drive key of the drive sleeve interacts with the pressurizing block when the drive sleeve is coaxial with the drill pipe cylinder; s is the effective acting area of the driving key at any position relative to the pressurizing block in the construction process, S=δ*π*(2(R+D)*B-B 2 ); Smax is the maximum value of the effective acting area of the driving key at any position relative to the pressurizing block in the construction process, Smax=δ*π*(2R*D+D 2 ); Smin is the minimum value of the effective acting area of the driving key at any position relative to the pressurizing block in the construction process, Smin=δ*π*(2(R+D)*(2B1-D)-(2B1-D) 2 ); Wherein, delta represents the ratio of the arc angle of the pressurizing block to 360 degrees, and is represented by delta=theta/360 degrees, theta is the arc angle of the pressurizing block of the drill rod, and B is the width of the area where the driving key and the pressurizing block interact at any position.
2. The drill rod pressurizing block according to claim 1, wherein an outer side surface of the drill rod pressurizing block consisting of the base body and the gradient wear layer is an arc surface.
3. The drill pipe press block of claim 1, wherein the matrix is a quenched alloy steel.
4. A drill rod for a rotary drilling rig, comprising a drill rod pressurising block as claimed in any one of claims 1 to 3.
5. A method of producing a gradient wear-resistant layer according to claim 1, comprising: uniformly distributing and fixing the matrixes of the plurality of drill rod pressurizing blocks on a tool matched with the inner side molded surface of the matrixes along the circumferential direction to form a multi-petal structure; Clamping the tool after fixing the drill rod pressurizing block on a rotary table, and calculating to obtain the rotary speed of the rotary table according to the laser cladding linear speed and the diameter of the circular arc plane of the drill rod pressurizing block, wherein the rotary speed of the rotary table and the feeding speed of a cladding head are adjusted in real time according to the change of the diameter of a cladding area, so that the cladding linear speed and the lap rate of the cladding layer along the direction from the outer diameter to the inner diameter are consistent, and the cladding layer with consistent thickness is obtained; Determining the number of cladding layers of the gradient wear-resistant layer according to the thicknesses of different areas of the gradient wear-resistant layer and the thickness of a single cladding layer, moving a laser spot scanning path from the outer side surface of a drill rod pressing block to the inner side surface of the drill rod pressing block, closing laser after the cladding of the previous layer is completed, and moving the laser spot scanning path to the outer side of the pressing block again to start the preparation of the next cladding layer; and preparing each subsequent cladding layer by adopting a high-speed laser cladding process until the preparation of all cladding layers is completed.
6. The method according to claim 5, wherein the angle θ between the laser beam and the surface of the area to be clad is maintained between 80 ° and 90 °.
7. The method according to claim 5, wherein, The parameters of the ultra-high speed laser cladding process comprise coating thickness of 0.3-0.4mm, laser power of 4000-4500W, cladding linear speed of 20-24mm/s, overlap ratio of 65-75%, powder feeding amount of 45-50g/min, shielding gas flow of 15-20L/min and powder feeding gas flow of 10-12L/min, wherein the powder is iron-based high speed laser cladding powder; The parameters of the high-speed laser cladding process comprise the thickness of a coating of 0.7-0.8mm, the laser power of 4500-4700W, the cladding linear speed of 9-10mm/s, the lap joint rate of 65-75%, the powder feeding amount of 48-54g/min, the flow rate of protective gas of 14-16L/min and the flow rate of powder feeding gas of 6-9L/min; the powder is iron-based high-speed laser cladding powder.
8. The method according to claim 7, wherein the iron-based high-speed laser cladding powder comprises 2-2.6% of C, 5-7% of Cr, 5.5-7% of V, 0.9-1% of Si, 0.3-0.6% of B, the balance of Fe, and has a spherical powder particle shape and a powder particle size of 20-53 μm.
9. The method for manufacturing the tool according to claim 5, wherein the tool comprises a cylinder, a side stop block, a lower stop block and an outer stop block; the surface of the cylinder body is respectively fixed with a side stop block and a lower stop block, the side surface profile of the side stop block is consistent with the side surface profile of the drill rod pressurizing block, the lower stop block is a cylinder, the outer stop block passes through the cylinder and is connected through a bolt, the inner side of the outer stop block is an arc surface, and the diameter of the arc is consistent with the diameter of the outer side of the drill rod pressurizing block; The side check blocks, the lower check blocks, the outer check blocks and the barrel body surface form a groove for inserting the drill rod pressurizing block, the left side surface and the right side surface of the drill rod pressurizing block are in seamless fit with the side check blocks positioned on the two sides of the drill rod pressurizing block, and the outer check blocks are tightly pressed on the drill rod pressurizing block by screwing bolts.

Description

Drill rod pressurizing block, rotary drilling rig drill rod and preparation method of gradient wear-resistant layer Technical Field The invention relates to a drill rod pressurizing block, a drill rod of a rotary drilling rig and a preparation method of a gradient wear-resistant layer, and belongs to the technical field of mechanical equipment. Background The rotary drilling rig is used as important equipment in the field of engineering machinery, and the working process mainly depends on a drill rod to transmit power load to a drilling bucket, and the rotary drilling rig rotates forward to break rock and soil. The drill rod is generally composed of a plurality of seamless steel tube sleeves with different diameters, and driving keys and pressurizing blocks are welded on the periphery of the outer ring of each drill rod for transmitting loads such as torque, axial pressure and the like. When subjected to severe conditions such as hard rock, the drill pipe will be subjected to significant reaction impact loads. Therefore, in order to improve the efficiency in the construction process, a large driving load needs to be applied to the bearing surface of the pressurizing block, and the theoretical load per unit area is about 40MPa. However, since the drive key, which applies the drive load, requires up and down movement, there is a radial clearance between it and the drill rod sleeve. Meanwhile, the drill rod is subjected to irregular transverse load in the construction process, and the drill rod and the driving key generate transverse relative motion, so that the interaction area between the driving key and the pressurizing block is influenced, and the surface load of the pressurizing block is increased. Although the pressurizing block is subjected to integral quenching treatment, the surface of the pressurizing block still generates uneven wear, serious crushing and other failures under the action of heavy load, thereby influencing the working efficiency and the operation safety of the rotary drilling rig. Disclosure of Invention The invention aims to overcome the defects of the prior art and provides a preparation method of a drill rod pressurizing block, a rotary drilling rig drill rod and a gradient wear-resistant layer. In order to solve the technical problems, the invention provides a drill rod pressurizing block which is fixed on the outer side surface of a drill rod cylinder and used for bearing downward pressure of a driving sleeve, and the drill rod pressurizing block comprises a base body and a gradient wear-resistant layer fixed at the upper end of the base body, wherein the upper end profile of the base body is consistent with the lower end profile of the gradient wear-resistant layer; the upper end profile of the gradient wear-resistant layer is a plane; the gradient wear-resistant layer comprises a coating II and a coating I, wherein the thickness of the coating II gradually increases from the outer side of the drill rod barrel to the outer side, the thickness of the coating I is kept unchanged, the coating I is positioned on the outer side of the coating II, and the radial direction refers to the diameter direction of the section of the drill rod barrel. Further, the outer side surface of the drill rod pressurizing block formed by the matrix and the gradient wear-resistant layer is an arc surface. Further, the thickness of the first coating layer is H1, the width of the first coating layer is 2B1-D, the width of the second coating layer is 2D-2B1, and the gradient thickness H is expressed as H=H2+ (Smax-S)/(Smax-Smin) ×(H2-H1); Wherein, B1 is the width of the area where the drive key of the drive sleeve interacts with the pressurizing block when the drive sleeve is coaxial with the drill pipe cylinder; s is the effective acting area of the driving key at any position relative to the pressurizing block in the construction process, S=δ*π*(2(R+D)*B-B2); Smax is the maximum value of the effective acting area of the driving key at any position relative to the pressurizing block in the construction process, Smax=δ*π*(2R*D+D2); Smin is the minimum value of the effective acting area of the driving key at any position relative to the pressurizing block in the construction process, Smin=δ*π*(2(R+D)*(2B1-D)-(2B1-D)2); Wherein, delta represents the ratio of the arc angle of the pressurizing block to 360 degrees, and is represented by delta=theta/360 degrees, theta is the arc angle of the pressurizing block of the drill rod, and B is the width of the area where the driving key and the pressurizing block interact at any position. Further, the matrix is made of alloy steel after quenching treatment. A drill rod of a rotary drilling rig comprises a drill rod pressurizing block. A method of preparing a gradient wear layer comprising: uniformly distributing and fixing the matrixes of the plurality of drill rod pressurizing blocks on a tool matched with the inner side molded surface of the matrixes along the circu