Papers by Keyword: Diamond Bit

Abstract: This paper introduces the application of orderly arranged diamond bit and the technology of realizing diamond orderly arrangement in bit. Two kinds of conventional bits and one bit with diamond orderly arrangement were used in the test to drill reinforced concrete. By experimental results: under the same conditions (same matrix, same diamond grade and concentration), the drilling speed of orderly arranged diamond bit is increased by 13.1%, the life is increased by 11.5%, compared with the conventional diamond bit. The drilling speed of orderly arranged diamond bit is increased by 15.8%, the life is increased by 8.9%, compared with the conventional bit which the matrix is same but the diamond concentration is 5% higher. On the basis of saving diamond and reducing cost of bit, orderly arrangement can still improve the efficiency and life of drill bit, it embodies the superiority of diamond bit with diamond orderly arrangement.

Abstract: With diamond particles, metal powders and a special soft material as raw materials, this paper introduced some diamond bits to drill the superhard materials such as granite. Besides, the biology non- smooth theory was applied to the design of bit, and a new type of bit which is called bionic bit was introduced about its principle and manufacturing method. Numerical simulations and field tests of bionic bits showed that the optimalizing non-smooth degree was the most important factor of the design of bionic bit. By ANSYS finite element calculation when the non-smooth degree is 12.6%, the drilling bit wear is the smallest, 63% less than the ordinary bit. This paper prepared four bionic bits with the non-smooth degree 13% and four ordinary bits to drill the granit in gold mine, the average life and drilling speed of bionic bits increased by 29.8% and 21.3% more than ordinary bits.

Abstract: This article introduces the biology non-smoothness, which generally exists in the natural environments. The various superficial shape of the biological living organism, regardless if it is on the land, in the sea, or in the air, often has the non-smooth surface, which has evolved for adapting to the different living conditions. The non-smooth surface has the characters of reducing resistance, anti-adherence, and anti-friction. These characteristics have been successfully applied to reduce resistance on airplane surface, reduce sticks on plough surface and wear the engine piston surface. The article also studied the bionic non-smooth drilling bit, applying the bionic non-smooth theory to the design of diamond bit, the JBD-75S bionic non-smooth diamond bit was developed. Field trial proved that bionic bit was superior to conventional bit both in the drilling effectiveness and in lifetime.

Abstract: The software CFDesign was used for the analysis of flow field simulation of two different kinds of drilling bit. The results showed that, if the waterway design of drilling bit was unreasonable, it could result in the following phenomenon: the local position of drilling bit could get severe erode of drilling fluid; the return of flow and eddy currents could be observed in the bottom of drilling well; negative pressure could be detected and might result in cavitation corrosion; the direction vector of flow field were diffused and resulted in cross flow. The waterway structure of arc-bottom bit was more reasonable comparing that of flat-bottom bit.

Abstract: To reduce the friction coefficient between impregnated diamond bit and rock, experiments on addition of graphite to the matrix material of bit cutters were conducted. The cutters were made up of diamond contained working layers and binding layers. The friction and wear properties of cutters and binding layers were investigated using a pin-on-disc friction & wear tester with granite as tribopair. The results showed that with addition of graphite, the hardness and friction coefficient of binding layer decreased, but its wear resistance increased; compared to cutters without graphite, those cutters containing graphite had lower wear loss and friction coefficient and their sliding wear process was much steadier, but diamond protrusion was still normal.

Abstract: By analyzing the rock fragmentation mechanism of diamond in diamond bit, the rock cutting depth with diamond, the area of diamond pressing into rock, the load on each diamond and the pressure on rock from diamond are calculated. After analyzing the result of calculation, it comes to a conclusion that volume crushing contributes most in rock fragmentation process of diamond bit. The method of choosing diamond quality in diamond bit is also explained as well. Selecting the quality of diamond plays a vital role in product performance. The effectiveness of diamond bit is involved with not only the density and particle size of diamond, but also the quality of diamond. Based on analyzing the rock fragmentation mechanism of diamond, this paper researches on selecting diamond quality.

Abstract: Based on mass experiments, gain the relation between the consistence of diamond bit and life, power consumption and granularity. Considering the relation of them, deduce a new method of calcuation for consistence design of diamond bit according to the given depth map of incising rock with diamond. Proved by practice, the method of calculation has a better practicability and veracity.