Self-cooling floating rolling-sliding composite bearing

Abstract

The invention provides a self-cooling floating type rolling-sliding composite bearing, which includes an inner rotator, an outer rotator, and an annular installation groove between the inner rotator and the outer rotator, and several rolling elements are installed in the annular installation groove and a number of floating support blocks, the floating support block is provided with a hollow cavity, and the hollow cavity is filled with a low-melting point metal, and the inner rotator and the floating support block are both made of a wear-resistant material with good stretchability. When the low-melting-point metal in the floating support block changes into liquid, the height of the floating support block is greater than the diameter of the rolling body. By implementing this technical solution, the self-cooling of the rolling-sliding composite bearing can be quickly realized, and the occurrence of thermal wear can be avoided; and the rolling-sliding composite bearing itself can withstand higher loads and rotating speeds, and is used to install a detachable connection at the core of the drill bit. The drill bit can effectively improve the drilling efficiency of the composite drill bit.

Description

technical field [0001] The invention relates to the technical field of drilling tools, in particular to a self-cooling floating sliding composite bearing. Background technique [0002] The drill bit is a rock-breaking tool used in drilling engineering to break rock and form a wellbore. Conventional drill bits used in today's drilling engineering mainly include three-cone drill bits, polycrystalline diamond compact drill bits (ie PDC drill bits) and rotary drill bits (also known as rotary punch drill bits or drill bits). [0003] The PDC drill bit is a kind of drill bit that uses the polycrystalline diamond composite sheet (ie PDC tooth) to scrape or shear the rock to break the rock. Due to the outstanding advantages in the performance of cutting elements and rock-breaking methods, the rock-breaking efficiency of PDC bits in soft to medium-hard formations is significantly higher than that of tricone bits. When the PDC bit drills in a relatively hard formation, the rock is b...

AI Technical Summary

Problems solved by technology

Conventional sliding bearings have a large load-bearing area and can withstand heavy loads, but the friction coefficient of the bearing friction pair is large, and the frictional heat generation rate is high. Under the condition of poor lubrication and cooling conditions, it is not suitable for high-speed operation.

The contact between the friction pairs of rolling bearings is high point-line contact, and the bearing parts are in rolling operation during operation, so the friction coefficient is small, the frictional heat generation rate is low, and it can withstand high speed, but because of the point-line contact, the Hertz stress High, not suitable for use under heavy loads or impact conditions

Thereby, there are the following technical problems in the bearing connection provided between the broken drill bit and the drill bit body: 1. The broken drill bit and the drill bit are continuously cutting the rock under high load, strong impact and high rotating speed, and the heat generated due to intense friction will make the The drill bit reaches a very high temperature. When the temperature exceeds the maximum thermal load, the wear rate of the drill bit to the bearing will increase significantly. If there is no cooling condition, it will easily lead to the occurrence of thermal wear.

2. Although the frictional heat generation rate of rolling bearings is relatively low, the Hertz stress is high, and it does not have the characteristics of high speed and heavy load

[0005] Therefore, in view of the above technical problems, it is urgent to study a connecting bearing that can be cooled quickly when the broken drill bit and the drill bit body rotate at high speed to cut rock, so as to avoid the occurrence of thermal wear when the cooling condition is not available.

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