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Alexander Boynton

"Perforator for wells", "Stage-lift flowing device", "Milling tool", "Automatic stage lift flowing apparatus for wells", "Pneumatic gun, bellows type", "Automatic well plowing device", "Measuring and recording device", "Flowing device, tubing, and casing flow", "Valve", "Rotary reamer", "Stage-lift flowing device", "Washing tool", "Pressure regulator", "Non-pipe-mashing wrench", "Stage-lift flowing device", "Bailer", "Method of and device for cementing wells", "Level maintainer for shackle rod lines", "Differential stage lift flow device", "Polished rod rotor", "Stage-lift flowing device", "Latch", "Cable pull overshot", "Differential flow device with valve controlling means", "Well testing tool", etc.


Hundreds of brilliant inventions and patents wrote genius American inventor from Texas Alexander Boynton in the period from 1918 to 1944 for Military and Oil Industries. Many of them are still relevant today.

Comparing his inventions with modern methods and technologies of development oil and gas well appears an amazement, how such progressive ideas are still lying in the archives and have not been applied. For example, compare the patent of "Perforator for wellsUS 2315496 (Nov 28, 1938) with modern perforations methods of opening the casing, cement and productive formations: abrasive water-jet perforations or slot perforations ("PetroWikiPerforating methodsBullet gun perforating, Abrasive perforating methods,  Water jetsShaped charges").

Already in 1938 (application date) Alexander Boynton in his patent US 2315496 offered cutting technology with continuation perforation through the casing, cement in to productive formation. Cutting was carried out by jets of working fluid under high pressure. The device has a ball-valve for forward and back flushing, centralizer of four stiffeners, and cutting nozzles sunk in to perforator body (for increase the length of nozzles, and correspondingly for more deep-cutting effect, because inside the perforator workflow speed dramatically decreases). In his another patent US 2229636 (1941), Alexander Boynton described the main principles of operation of the hydraulic brake with spring return mechanism, that was ready-made solution for continuous rectilinear motion of the cutting jets along the well-bore. All this is now used in slot perforation technology. Alexander Boynton also described mechanical slot perforation technology (patent US 1801482, 1931), and many other useful inventions now used in Oil and Gas  Industry


Some of his inventions for over 80 years. With the development of scientific and technical progress changed techniques and methods of using, improve and perfect equipment and parts, but the technology and principles of application remain the same.

Patent US1801482
Patent US2459933
Untitled surface inaccurate patent



"Perforator for wells". Patent US 2315496. Alexander Boynton. Apr. 6, 1943"Method of perforating well casing and of cutting openings through cement and formations of the earth exterior of the casing".

"Apparatus for increasing productivity by cutting openings through casing, cement and the formation rock". Patent US 5445220. Alexander Gurevich, Ralph Horlacher. Aug 29, 1995

"Method of oil well productivity increase". Patent  US 5337825Leon Marmorstein, Ignaty Petuhov, Vladimir Sidorov, Piotr Aleksandrov, Valentin Grebennikov, Aug 16, 1994.

Patent US2315496
Patent US5445220
Untitled surface inaccurate patent

"Well testing device, rathole type". Patent US 2229636. Alexander Boynton. Jan 28, 1941"This invention relates to improvements in well".

"Hydra-jet slotting tool". Patent US 4346761. Neal Skinner, Harry Braswell. Aug 31, 1982. "Apparatus for controlling the rate and extent of cutting slots in flow conductors, particularly casing in wells".

"Device for cutting of slot-like key seats in wells by a hydroabrasive method". Patent US 7140429. Valentin Grebennikov, Anatoly Ivanov, Artem Ivanov. Nov 28, 2006

Patent US2229636
Patent US4346761
Untitled surface inaccurate patent

"Milling tool". Patent US 1801482. Alexander Boynton. Apr 21, 1931"Milling tool for catting casing of oil, gas and water wells".

"Hydro-mechanical slot perforation". Patent RU 2459933. Mary Pasvandy. Dec 17, 2006.

"Method/system for increasing productivity of oil, gas and hydrogeological wells". Patent US 6651741-7073587. Yakov Bassin, Valentin Grebennikov, Boris Goldstein, Anatoly Ivanov, Leon Marmorshteyn Nov 25, 2003 - Jul 11, 2006.



Later slot perforations technology studied in various geologists and scientists from different countries. 


In the seventies (1970-1975) slot perforation technology issues were engaged Institute of Oceanology (IORAN) and Scientific Research Institute of Mining Geo-mechanics (VNIMI) (St. Petersburg, Russia). The results of their research and development was patent for classical slot perforation RU 1623290 July 24 1972 (Inventors: E. Goncharov, A. Shabarov, V. Sidorov, N. Krotov, I. Petukhov) and device, capable create longitudinal slots in the wells, works on the hydraulic (Right drawings). 


Drawings are very similar to patents of Alexander Boynton: US 2315496 (Apr. 6, 1943) and US 2229636 ( Jan 28, 1941). 


First practical slot perforation technology test in the real oil well were successfully made at the end of 1975


Since 1980, slot perforation technology has been recommended for use in Oil and Gas Industry. Currently classical slot perforation technology is absolutely open for use. For more information:


"Scientific Research Institute Mining Geo-mechanics and Mine Surveying"

"Ministry of Energy of the Russian Federation"

"Russian Academy of Sciences"

Inter-industry Scientific Research Center "VNIMI"

RUSSIA, 199106, St. Petersburg,

B.O., 22-line, 3, Building 3, lit. B

Patent-Licensing Group


Presentation of slot perforation technology in the United States was in 1987 on the "Oil and gas conference" in Texas. Slot perforation technology test in the real two gas wells were successfully made by "Marmorshteyn Oil Company" in 1996 in Albert Load, Michigan for "Shell E & P Technology Company". Department of Geophysics of Stanford University also gave a positive assessment to slot perforation technology (PDF-files).

Patent US2315496
Patent US2229636
Untitled surface inaccurate patent


"Classical" slot perforation technology - opening casing, cement and productive formation by cutting of continuous deep longitudinal slots along the well-bore (all-in-one-cycle process). For creation of slots is used a special tool with hydraulic principle, that cuts slots by rectilinear and constant movement of abrasive cutting waterjets along the wellbore, and without moving of tubing.


Main idea of "classical" slotting perforation  technology:

Unloading annular compression stresses in the near wellbore zone (for increases of permeability and porosity, and accordingly increasing the productive inflow). Slotting perforation technology - the only method, supposed to unload annular compression stress conditions around the wellbore.

Opening a large casing area and creation of a large drainage penetration’s zone in the productive formation (for good hydrodynamic connection well with the productive formation).

"Classical" slot perforation - absolutely environmentally friendly technology (sand and water) without any chemical or mechanical additives.


Last measuring test, made by "Halliburton" in 2014showed the cutting depth of slot perforation technology is near 3.3 feet (1 meter), but depending on the hardness of rocks mathematically cutting depth can not exceed 5.0 feet (1.5 meters).

Based on "classical" slotting perforation technology were written more then 50 full public books, around 600 patents, more than 100 public patents already "open" for free use. 


Slot perforation technology was successfully used in thousands oil and gas wells in different places: Azerbaijan, Brazil, Canada, China, Eastern and Western Siberia, Jordan, Komi Republic, North Caucasus, Poland, Russia, Udmurtia, Ukraine, United States, Urals, Uzbekistan and Yemen.

Some of slot perforation technology service-companies: "Biddless", "DOGEP", "Dyna", "Exalo", "Hydro-Sandblast", "Hydro-Pressure", "Hydro-mechanical slot perforation", "Maxxwell Production", "Nekko", "Nexus", "Nord Service", "Octopus", "Oil Tech Group", "Kontact", "Komplex".

Maxxwell Production - slot perforation technology




Over the past years in the United States and in other countries began to appear a huge number of patents regarding slot perforation technology. These "inventions" have not brought a lot of progress in that direction, basic principles remain the same: opening casing, cement and productive formation by cutting of continuous deep longitudinal slots along the wellbore. Enterprising "inventors" copied old patents with some modifications does not affect the method of opening generally. From changes of directions of cutting slots from top to down or vice versa, or from left to right and back,  nothing changed. Also, there was nothing new in patents regarding order of use slot perforation technology with numerous methods of simulations (before or after), especially since it has long been used in previous practices.

Classical slot perforation technology is free to use and does not belong to anyone. However using the absence of sufficient information regarding slotting perforation technology some companies, mainly the poor intermediary, Internet or spoken-business companies, primarily related to Oil and Gas Industry only through the phone, sometimes under the cover of some insignificant patent (one of existing 600, for example), sometimes even without a single document, began to claim some rights for whole slot perforation technology as their own property. Typically, such companies do not have practice of wells recovery, special underground tool, specialists or experts, and of course, they does not make any scientific or technological research and developments. The activities of such companies does not go beyond the theoretical or philosophical conversations with the similar intermediaries.


In the Internet or mass-media possible to find a lot of the following brave statements: "our technology", "own technology", "new technology", "private", "innovative", "proprietary", "revolutionary", "special", etc. To accentuate belonging of slot perforation technology exactly to only their own companies, for technology is usually given the name of the company or distorted name of the technology beyond recognition: "hydro-jet", "hydro-cutting", "water-jetting", "petroleum", "special", "engineering", "scientific", "research and developing", etc. although in reality it is slot perforation technology.

Maxxwell Production - slot perforation technology

Activities of various intermediary companies harms the development of Oil and Gas Industry. They are not only raise the prices for recovery services in twice or more times, but also distort reality due to technical incompetence, and advertising absolutely unreal things, and rewriting it gently from each other. For example, "50-65 feet (15-20 meters) penetration depth", "increase production up to 300-600%", or regarding slot perforation tool: "fully oriented", "balancing", "radio-controlling", "gyro-telemetry", "positioning", "data transferring",  "recording black box", "101 generation" and other fictions.

With inventions of underground slot perforation tool the things are in a better position, than with technology. Firstly, fiction's projects not patent. Secondly, in patents for equipment actually observed some progress. Despite the fact that the operating principles remain the same, design, separate units and parts obviously improved to a more long period of operation, ergonomics, stability, ease of manufacturing and low cost. Patents on the equipment appears much less than on the technology, because here can not use just philosophical arguments, here necessary calculations and real practice tests. Big progress achieved patents for hydro-mechanical slot perforation tool, for example.


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