Front connector of high air-pressure down-the-hole hammer

Abstract

The invention provides a front connector of a high air-pressure down-the-hole hammer. A wear resistant material layer is welded on an excircle with the maximum diameter on the front end of the front connector, the welding seam direction of the wear resistant material layer is along the axis of the front connector or along the circumference of the front connector, or forms an angle of inclination with the axis of the front connector, and the wear resistant material layer is a tungsten carbide wear resistant welding rod. By welding the wear resistant material layer with a certain thickness on the excircle on the front end of the front connector, when a hammer works, the high speed returning debris firstly scours and abrades the wear resistant material layer welded on the surface of the front connector under the action of a high pressure gas, thus avoiding that the front end of the front connector directly withstands the violent scouring and abrasion of the debris and greatly increasing the service life of the front connector.

Description

technical field [0001] The invention relates to a down-the-hole hammer for gas rock drilling, in particular to a front joint of the high-wind pressure down-the-hole hammer. Background technique [0002] The high wind pressure down-the-hole impactor is composed of rear joint, outer casing, check valve, cylinder, air distribution seat, piston, guide sleeve, retaining ring, front joint and other parts. The whole impactor is connected with the down-the-hole drill bit through the front joint and the retaining ring, and the drill bit and the front joint are splined. When working, the compressed air is used to drive the piston of the down-the-hole impactor to impact the down-the-hole drill bit with a large impact energy and high frequency. It is carried back to the surface by high-pressure airflow, so as to realize drilling. When the rock debris produced by the impactor is blown out of the air by the compressed air, it first scours and abrades the front joint end of the impactor....

AI Technical Summary

Problems solved by technology

In the manufacturing process, the front joint generally adopts the heat treatment process of integral quenching, and the hardness is about HRC40 degrees. Deep grooves are often washed out on the outer surface of the outer circle, and sometimes it directly causes rapid wear of the outer circle part of the outer sleeve and the front joint. Even worn out, causing the outer casing and the front joint to fail prematurely together. In some hard and abrasive formations, one impactor needs to replace two front joints, resulting in the service life of the front joint cannot match the life of other parts. Matching has seriously affected the full use of the overall service life of the impactor

[0003] In summary, the existence of these problems will directly affect the increase in the cost of the impactor, thereby increasing the cost of the entire project

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