1930: Hydraulic ram hammer of John A. Zublin
In 1930, John Adolphus Zublin patented a fluid-driven hammer mechanism. The patent consists of multiple mechanisms to convert the hydraulic energy to a percussive motion and some possible piston retraction concepts.
The hammer piston is moved by a spring towards the valve, this will close the fluid passage, accelerating the valve and piston by using the water hammer effect. The valve displacement is limited by a small rod, so the passage will be opened and the hammer piston continues to hit the anvil.
The patent also mentions a piston retraction without any springs, using different area sizes and connecting the hammer piston's back area to the outside of the drill.
By using a small orifice inside the flow path at the anvil a pressure drop will occur depending on the flow. As the back surface of the piston is connected to the ring annulus, the pressure will press against the front surface (186) will push the hammer piston upwards, against the fluid flow.
1946: Bassinger Tool
Ross Bassinger was developing hydraulic percussion tools in 1940 with his company "Bassinger Tool Company". The valve was placed around the hammer piston instead of being a valve head. His son Grey Bassinger was continuing his developments afterward. Passenger tools were able to gain an advantage over rotary drilling.
The rate of penetration was about 30 % higher while drilling in Oklahoma. Bassinger Tools were also used by the shell for multiple wells in Alberta.
The use of roller cone bits was challenging due to the impulse transfer through the bearings and the use of regular teeth. Button Bits were still not invented in the 1950s. Various drill bits have been tested, best results were obtained using a roller cone bit with sleeve bearings instead of ball bearings.
Using a rubber coating the abrasive wear of the hammer piston could be reduced so the hammer could be operated for up to 14 hours. The rate of penetration was significantly higher compared to rotary drilling, for example, the ROP in anhydrite and gypsum rock in Canada was about 2,4 m/h compared to 1,7 m/h with rotary drilling.
1968: Hydraulic Percussion Drill of Pan American Petroleum
The invention of a new kind of hydraulic percussion drill at Pan American Petroleum Corp. (later known as Amoco, then BP) by Renic P. Vincent in 1968 was another milestone. Using 7'' and 11'' tools they were able to increase the rate of penetration about three to five times compared to rotary drilling.
The 11” tool had a length of 2,3 meters and a hammer piston mass of 400 kg. Still, roller cone bits were used as drill bits.
