阅读说明：本技术 一种冠部轮廓偏移的pdc钻头刀翼 (PDC drill bit blade with crown profile offset ) 是由 邓嵘 黄安龙 陈科 张家彧 刘建平 刘瑜 何清 江炫君 于 2020-06-23 设计创作，主要内容包括：本发明公开一种冠部轮廓偏移的PDC钻头刀翼,钻头刀翼轮廓曲线主要包括：内锥、圆弧修正段、内凹偏移段、外锥、肩部、保径段。所述内锥与圆弧修正段相切,所述圆弧修正段为向下凸的圆弧段,所述内凹偏移段为向上凸的圆弧段与圆弧修正段外切,所述圆弧修正段与外锥内切,所述外锥与肩部内切,所述肩部与保径段相切。本发明涉及的一种冠部轮廓偏移的PDC钻头刀翼能降低常规的PDC钻头刀翼冠部主切削段所受的冲击载荷、改善刀翼冠部的切削齿的磨损和崩碎、提升钻头的稳定性、延长PDC钻头使用寿命、提升破岩效率。(The invention discloses a PDC drill bit blade with a crown profile offset, wherein a profile curve of the drill bit blade mainly comprises the following components: the inner cone, the arc correction section, the concave offset section, the outer cone, the shoulder and the diameter protection section. The inner cone is tangent to the arc correction section, the arc correction section is a downward convex arc section, the inward concave offset section is formed by externally tangent of an upward convex arc section and the arc correction section, the arc correction section is internally tangent to the outer cone, the outer cone is internally tangent to the shoulder, and the shoulder is tangent to the gauge protection section. The PDC drill bit blade with the deviated crown profile can reduce the impact load borne by the main cutting section of the crown of the conventional PDC drill bit blade, improve the abrasion and the breakage of the cutting teeth of the crown of the blade, improve the stability of the drill bit, prolong the service life of the PDC drill bit and improve the rock breaking efficiency.)

1. A PDC drill bit blade with a crown profile offset comprises a 1-inner cone, a 2-arc correction section, a 3-inner concave offset section, a 4-arc correction section, a 5-outer cone, a 6-shoulder and a 7-gauge section, wherein the 1-inner cone is tangent to the 2-arc correction section, the 3-inner concave offset section is circumscribed to the 2-arc correction section and the 4-arc correction section, the 4-arc correction section is inscribed to the 5-outer cone, the 5-outer cone is inscribed to the 6-shoulder, and the 6-shoulder is tangent to the 7-gauge section.

2. The PDC bit blade with an offset crown profile of claim 1, wherein the 2-arc and 4-arc segments are downwardly convex arc segments with equal arc lengths in the same direction and the center of the arc segments are on the same horizontal straight line.

3. The PDC bit blade with crown profile offset of claim 1, wherein the 3-concave offset section is an upwardly convex circular arc section, and the upward offset is in an offset range of 1.3-5.7 mm.

4. A crown profile offset PDC bit blade in accordance with claim 1 wherein said 5-outer cone and said 6-shoulder are outwardly convex circular arc segments.

Technical Field

The invention belongs to the technical field of oil and gas drilling, and relates to a PDC drill bit blade with a crown profile offset for petroleum, natural gas and geological exploration.

Background

Along with the increase of the drilling depth, the drilling difficulty is more and more, higher requirements are also put forward for the drill bit, in a high-hardness and high-abrasiveness stratum, the top of a blade crown of the drill bit is easy to be worn and damaged, cutting teeth are easy to be worn and damaged by impact, and the service life of the drill bit is short.

Research shows that the cutting teeth at the crown of the blade of the conventional PDC drill bit are easy to break up due to large impact caused by the existence of transverse vibration, and the drill bit is worn and failed in advance due to large load borne at the crown. If the profile design of the PDC drill bit blade crown is improved, the impact and load on cutting teeth of the drill bit blade crown can be effectively reduced, the service life of the PDC drill bit is prolonged, and the drilling efficiency is improved. The above problems are solved by designing a PDC bit blade with an offset crown profile.

Disclosure of Invention

To avoid the above problems the present invention proposes a PDC bit blade with an offset crown profile: the blade can disperse the stress concentration of the profile of the crown part of the blade of the bit, reduce the abrasion of the cutting teeth of the crown part and the crown part of the blade of the PDC bit, prolong the service life of the bit and improve the drilling efficiency.

In order to solve the technical problem, the technical scheme adopted by the invention is as follows: a PDC drill bit blade with a crown profile offset structurally mainly comprises an inner cone, an arc correction section, an inwards concave offset section, an outer cone, a shoulder and a gauge protection section, wherein the inner cone is tangent to the arc correction section, the inwards concave offset section is circumscribed to the arc correction section, the arc correction section is inscribed to the outer cone, the outer cone is circumscribed to the shoulder, and the shoulder is tangent to the gauge protection section.

The further technical scheme is that the arc correction section is a downward convex arc section.

The further technical scheme is that the concave offset section is an arc section which is convex upwards.

The further technical scheme is that the outer cone and the shoulder are arc sections which are convex outwards.

The further technical scheme is that the design steps of the profile curve of the PDC drill bit blade are as follows:

determining a main cutting arc section of the arc of the crown of the PDC bit blade based on the profile shape of the crown of the PDC bit blade from the straight line, the arc and the straight line, and determining the range and the offset of the inward offset of the profile of the main cutting section of the arc of the crown of the PDC bit blade;

selecting an offset mirror image line, and mirroring the offset main cutting arc section;

selecting a correction arc reference point, and correcting the distance difference between the left offset front blade crown main cutting segment and the left offset rear blade crown main cutting segment by using an arc segment;

and step four, determining a corrected mirror image straight line, and mirroring the left arc correction section to obtain a right arc correction section.

The further technical scheme is that the offset range is 1.3-5.7 mm.

The invention has the following advantages:

the PDC drill bit blade with the profile offset crown can optimize the profile design of the crown of the drill bit, disperse stress concentration on the profile of the crown of the drill bit blade, reduce the abrasion of the crown of the drill bit blade and main cutting teeth, prolong the service life of the drill bit, improve the drilling efficiency and reduce the production cost.

Drawings

FIG. 1 is a schematic view of a profile curve of the present invention;

FIG. 2 is a schematic structural diagram of the contour curve design step of the present invention.

Shown in the figure: 1-inner cone, 2-arc correction section, 3-concave offset section, 4-arc correction section, 5-outer cone, 6-shoulder, 7-diameter protection section, 8-main cutting arc section, 9-offset and 10-offset rear main cutting arc section.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

A PDC bit blade with an offset crown profile according to the present invention is further described with reference to the accompanying drawings and embodiments. The following examples are given solely for the purpose of illustration and are not to be construed as limitations of the present invention, and any variations, equivalents, and improvements made within the spirit and principles of the invention are intended to be included within the scope of the invention.

As shown in figure 1, the PDC drill bit blade with the crown profile offset comprises a 1-inner cone, a 2-arc correction section, a 3-inner concave offset section, a 4-arc correction section, a 5-outer cone, a 6-shoulder and a 7-gauge section, wherein the 1-inner cone is a straight line section, the 1-inner cone is tangent to the 2-arc correction section, the 2-arc correction section is a downward convex arc section, the 3-inner concave offset section is an upward convex arc section, is circumscribed with the 2-arc correction section and the 4-arc correction section, the 4-arc correction section is that the downward convex arc section and the 2-arc correction section have the same radian and are inscribed with the 5-outer cone, the circle center is on the same horizontal line, and the 5-outer cone is a outward convex arc section and is circumscribed with the 6-shoulder, the 6-shoulder is an arc section which is convex outwards and is tangent to the 7-diameter-protecting section, and the 7-diameter-protecting section is a straight section.

As shown in fig. 2, the design steps of the profile curve of a PDC bit blade with a crown profile offset according to the present invention are:

determining 8-main cutting arc sections of PDC bit blade crown arcs based on the profile shapes of the PDC bit blade crown sections of straight lines, arc and straight lines, and determining the inward 9-offset range and 9-offset of 8-main cutting arc sections of the PDC bit blade crown;

selecting an offset mirror image line ab, and mirroring the 10-offset main cutting arc section;

selecting correction arc reference points a and c, and correcting the distance difference between the 8-main cutting arc segment of the left offset front blade crown part and the 10-offset main cutting arc segment by using a 2-arc correction segment;

and step four, determining a corrected mirror image straight line df, and mirroring the left 2-arc corrected section to obtain a right 4-arc corrected section.

Although the present invention has been described with reference to the above embodiments, it should be understood that the present invention is not limited to the above embodiments, and those skilled in the art can make various changes and modifications without departing from the scope of the present invention.