Hole expanding drill bit

Abstract

The invention provides a hole expanding drill bit. The hole expanding drill bit comprises a drilling rod, a plurality of cutter bodies, hole expanding wings, lower blades, an expanding oil cylinder, an upper blade, a slurry tube and a hydraulic oil tube assembly, wherein the cutter bodies are fixed on the blades; the lower blade is horizontally uniformly distributed and fixed on the peripheral surface of the lower part of the drilling rod in a radial form; the hole expanding wings are positioned above the lower blade and symmetrically formed along the drilling rod in the radial direction; an oscillating rod is mounted on a pin seat on the peripheral surface of the drilling rod through a hinge pin pivotal shaft, and the end of the oscillating rod is positioned into a groove in a cylinder barrel; the slurry tube is positioned in holes of a piston and a piston hole of the expanding oil cylinder. According to the hole expanding drill bit, the combined drilling and excavating structure is adopted; the hole expanding wings can be opened by operating the expanding oil cylinder while expanding the bottom or hole, besides the function of drilling and excavating general piles with the same section, so that the pile end of a bearing file and the section area of a pile body can be increased; the drill bit can be used for building various bottom expanding piles and calabash piles, and has the characteristics of being high in single pile bearing capacity, ensuring the pile diameter, and being convenient to construct, stable and reliable to work, and long in service life.

Description

technical field [0001] The invention belongs to a drill bit for construction in the construction industry, in particular to a hole reaming drill bit. Background technique [0002] With the development needs of high-rise buildings, large bridges and urban subway infrastructure projects, long spiral equal-diameter pile drilling rigs have been widely used, due to the poor bearing capacity of equal-diameter piles. Therefore, in order to improve the bearing capacity of piles, a large number of new bearing piles such as expanded bottom piles and gourd piles are used in the foundation engineering construction, and the construction of these bearing piles will use the construction technology of prefabricated piles combined with drilling, expansion and grouting. That is to use the integrated drilling tool with drilling and reaming functions to drill holes, and ream the straight holes according to a certain distance according to the design requirements. After the concrete is fully sol...

AI Technical Summary

Problems solved by technology

At present, there are generally two types of reaming drills: mechanical reaming type and hydraulic reaming type. The mechanical reaming drill works by opening the reaming wing with the help of gravity when the drill pipe is lowered, and retracting it by itself with the help of the lever principle when it is lifted. This type of reaming drill has the problem that the size of the reaming hole cannot be guaranteed; while the hydraulic reaming drill uses a hydraulic expansion cylinder to expand and retract the hole. At present, the expansion cylinder is generally arranged on the outer wall of the drill pipe or the inner cavity of the drill pipe, and the expansion cylinder during the reaming process It is always in the erosion of compressed air, mud and other substances, and has high requirements for the machining accuracy and sealing performance of the expansion cylinder.

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