CN2208615Y

CN2208615Y - High-efficiency composite scraping drill

Info

Publication number: CN2208615Y
Application number: CN 94246228
Authority: CN
Inventors: 杨宝德; 缪青维; 周龙昌; 吴志明
Original assignee: China University of Petroleum East China
Current assignee: China University of Petroleum East China
Priority date: 1994-11-22
Filing date: 1994-11-22
Publication date: 1995-09-27
Anticipated expiration: 2004-11-22

Abstract

The utility model provides a blade of a high-efficiency composite scraping drill, mixedly embedded up by a hard alloy and diamond composite sheets. A blade body is divided into a front half part and a back half part; the front half part is embedded with the hard alloy and designed according to a positive rake angle of 10-20 DEG. The hard alloy embedded on the inside of the blade is arranged longitudinally, and the hard alloy on the outside is obliquely arranged. The back half part blade is designed according to a negative rake angle of 15-25 DEG and embedded with the diamond composite sheets. The blade of the bit has better self-sharpening property, does not cause the drilling pressure to be greatly raised during drilling wells, and keeps the longer service life of the bit.

Description

High-efficiency composite scraping drill

The utility model relates to the improvement of a kind of oil drilling with drag bit.

At present, the on-the-spot common three-winged bit that uses of oilfield drilling, husky more than one section during strata drilling in the east China oil field, its drill footage generally remains on 2000--2300 rice, and the while is along with the consumption of blade, drill bit rust, and carbide alloy can not be fine from sharp, therefore, want to continue to keep drilling depth just must strengthen the pressure of the drill, but strengthen the generation that the pressure of the drill will cause consequences such as hole deviation and drilling tool damage.Because husky one section stratum ubiquity hardcoat layer, common drag bit generally is difficult to drill this one deck position, the drill bit that must more renew, the application life of drill bit is short, drilling cost is increased substantially, increased the number of times that makes a trip simultaneously, prolonged well construction period and economic benefit decline.In order to prolong the application life of three-winged bit, adopting more method is the pre-grinding length that strengthens blade strength and suitable lengthen blade, even the blade of the certain-length that worn and torn in the drilling well course of work like this, residual altitude still can be kept certain ability to work.But improved like this effect is very limited, and therefore, all kinds of common drag bit that uses all fails to obtain considerable progress on increasing the service life at present.

The purpose of this utility model is that a kind of drill bit with carbide alloy and the composite structured blade of diamond compact will be provided, to prolong the application life of drill bit.

The purpose of this utility model is to realize like this, the blade of drag bit is composited by carbide alloy and two kinds of materials of diamond compact, and promptly the agent structure of blade is divided into two sections, leading portion tungsten carbide button material, press the positive rake angle design, angle is 10 °-20 °; Back segment is inlayed diamond compact, and by the negative rake design, angle is 15 °-25 °.

Fig. 1 is the schematic diagram of the compound drag bit that proposes according to the utility model;

Fig. 2 is the vertical view of the compound drag bit that proposes according to the utility model;

Fig. 3 is the structural representation of the compound drilling scraper that proposes according to the utility model.

Among the figure, 1-bit matrix, 2-blade, 3-diamond compact, 4-carbide alloy, 5-hydrophthalmia.

Further describe the concrete structure of the compound drilling scraper that the utility model proposes below in conjunction with accompanying drawing.

Accompanying drawing is the schematic diagram with compound drag bit of four blades.Four blades evenly distribute on the bit body circumference.Each blade divides two sections of front and back, and the positive rake angle design is pressed by first half tungsten carbide button, and angle is 10 °-20 °, and its inboard carbide alloy is vertical arrangement, and the carbide alloy in the outside is arranged askew; Latter half is inlayed diamond compact, and by the negative rake design, its angle is 15 °-25 °.

With this drill bit drilling well, the first half of its blade is used to drill top than broken ground, and latter half is used to drill the bottom than hard formation.The cutting angle of blade is to change design, and blade has preferably from sharp characteristic, can not cause increasing substantially of the pressure of the drill in drilling process, can keep than the drilling life of bit of growing.

Claims

1, a kind of drilling scraper is characterized in that, blade (2) body portion two parts, first half is designed to positive rake angle, and angle is 10 °-20 °, tungsten carbide button on it (4), the carbide alloy that is embedded in the blade inboard is vertically arranged, and is embedded in the carbide alloy arranged askew in the blade outside; Latter half is designed to negative rake, and angle is 15 °-25 °, inlays diamond compact (3) on it.