New Rotation-air Hammer Product Development

The air hammr drilling have so many advantages such as small drill pressure,low rotation speed, high ROP and preventing greatly the well deviation when drilling the hard,complicated,great steepness,easy deviation-formation,so it was the first option for the air drilling. However, the air hammer as the main gas drilling tools for breaking rocks also have some disadvantages.For example,bit drop off,the drill failure,can't using of horizontal wells,extended wells,directional wells.These disadvantages seriously affected the efficiency and air hammer drilling application.Based on the related theory abuot the domestic and international air hammer,according to rock drilling theory,designs a new rotary air hammer,which using the high pressure gas to achieve impact and rotary. The drill pipe do not rotation when it working,which can effectively reducing the forces of the drill string.The new air hammer designs a new fishing tool to avoid bit drop off and other underground accidents.To carry out the new air hammer-type-the rotation air hammer researchs will surely open up a new areas in directional wells, extended wells, horizontal wells,and it will be the main development direction of future air hammer.In this paper the specific work as follows:(1)Lierature research of air hammer in domestic and international. Collection of domestic and foreign air hammers in the literature, patents and using status in oil and gas fields.(2)Research of air hammer's structure and working principle. This paper collects the typicle structure of air hammer, understands the principle, determines the design principles and methods.(3)The overall structure design.Designed two types of rotary air hammer and optimized, using the rock drilling theory calculated operating parameters, structure parameters and performance parameters, using Pro/e 3D design software to establish air hammer solid model.(4)Strength check of major components.using theoretical calculation and finite element analysis method checked the spiral rod and screw the mother, the piston and the drive sleeve, drive sleeve and top solder strength.(5)Pistons-Bit impact dynamics analysis. Using the impact dynamics software ANSYS/LS-DYNA established a piston-bit dynamic model, analyzed the impact strength, optimized the piston and the bit,studied the impact Law of the energy transfer process and the relationship between the piston's end impact speed and maximum Von Mises stress.(6)According to the design of the rotary air hammer, a prototype was made and tested in outdoor to verify the feasibility of the design.