EP0110529B1 - High velocity fluid abrasive jet - Google Patents

High velocity fluid abrasive jet Download PDF

Info

Publication number
EP0110529B1
EP0110529B1 EP83306212A EP83306212A EP0110529B1 EP 0110529 B1 EP0110529 B1 EP 0110529B1 EP 83306212 A EP83306212 A EP 83306212A EP 83306212 A EP83306212 A EP 83306212A EP 0110529 B1 EP0110529 B1 EP 0110529B1
Authority
EP
European Patent Office
Prior art keywords
jet
passageway
particles
section
velocity
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP83306212A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0110529A2 (en
EP0110529A3 (en
Inventor
Mohammed A. Hashish
Yih-Ho Pao
Michael J. Kirby
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Flow Industries Inc
Original Assignee
Flow Industries Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Flow Industries Inc filed Critical Flow Industries Inc
Priority to AT83306212T priority Critical patent/ATE46846T1/de
Publication of EP0110529A2 publication Critical patent/EP0110529A2/en
Publication of EP0110529A3 publication Critical patent/EP0110529A3/en
Application granted granted Critical
Publication of EP0110529B1 publication Critical patent/EP0110529B1/en
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
    • B24C5/00—Devices or accessories for generating abrasive blasts
    • B24C5/02—Blast guns, e.g. for generating high velocity abrasive fluid jets for cutting materials
    • B24C5/04—Nozzles therefor

Definitions

  • This invention relates to abrasive loaded liquid jets, and particularly to high velocity abrasive liquid cutting jets.
  • abrasive particles It has long been known to accelerate abrasive particles with a jet of high velocity fluid. Such a jet may be used for cleaning and surface finishing applications. Dry and wet sand blasting are examples. In all such applications only the surface of the target material is removed and there is no deep penetration.
  • the fluid used in such applications is usually air or other gas.
  • existing nozzle designs do not allow the particles of abrasive to reach jet speed, or a substantial fraction thereof, resulting in far less than theoretical cutting capacity.
  • existing nozzles do not produce a coherent stream of abrasive-charged particles, resulting in insufficient cutting power and a large kerf.
  • the invention provides apparatus for producing an abrasive-laden jet characterised in that the particle-laden jet impinges upon the interior of the straight section such that the latter imparts to the particles a component of movement toward the centre of the jet sufficient to concentrate the particles of abrasive at the jet's centre as the jet exits from the output, and in that the straight section has a length of between 25 and 100 times its diameter whereby, in use, the particles of abrasive are accelerated to an exit velocity of at least 80 percent of the velocity of the liquid forming the jet.
  • the invention provides a method of producing a particle-laden jet characterised in that said particle-laden jet impinges upon the interior wall of the passageway at a predetermined point downstream from its inlet end and thereafter fills the entire cross-section of the passageway as the jet moves through the latter to its outlet end so as to impart to the particles a component of movement toward the centre of the jet, the length of the passageway being such that by the time the jet exits the passageway at the outlet end, the particles therein have a velocity of at least 80 percent of the velocity of the liquid forming the jet and are concentrated at its centre, the length of the passageway being between about 25 and 100 times its diameter.
  • the invention provides a method and apparatus for producing high velocity, abrasive loaded, coherent streams of liquid.
  • the invention maximises abrasive particle exit velocity and reduces nozzle wear to provide a long service life.
  • Figure 1 illustrates the first type of nozzle, a converging- diverging or venturi type nozzle. This type of nozzle has been found unsuitable for use in high velocity abrasive water jet cutting due to extreme nozzle erosion problems.
  • a second type of nozzle illustrated in Figure 2 has shown somewhat more promise.
  • This nozzle, called a straight nozzle includes a converging section 1 and a straight section 2 having a length (a) and a diameter (d). The sum of the length of straight section 2 and converging section 1 is the total length (L) of the nozzle. In present nozzles, the ratio of (a)/(d) is less than 20 and is much less for those nozzles where it is between 15.24 and 31.75 mm.
  • FIG. 3 shows a typical arrangement of components used in abrasive water jet cutting.
  • the drawing is broken for clarity.
  • a high pressure water jet nozzle having an orifice 7 of diameter (dn) receives high pressure liquid having a pressure (P) from a source (not shown) of high pressure liquid which may be for example a hydraulic intensifier or equivalent device.
  • a jet 8 emerges from orifice 7 and enters the convergent section 9 of a nozzle 11.
  • Convergent section 9 of nozzle 11 is also connected to a source (not shown) of abrasive particles 10 having a predetermined size (dp) and a flow rate (m).
  • the entrance of jet 8 into converging section 9 of nozzle 11 creates an area of low pressure 12 at the entrance to nozzle 11.
  • the materials used and the geometry of the apparatus must be adapted to the parameters defined above to produce a satisfactory nozzle.
  • FIG. 4 illustrates the characteristics of fluid flow in a high pressure fluid jet nozzle 21.
  • the drawing is broken away for clarity.
  • a jet 22 of high pressure fluid leaves an orifice 23.
  • Typical orifice diameters are from 0.254 to 12.70 mm with operating pressures from 34335 kPa (350 kg/cm 2 ) to 686,700 kPa (700 kg/cm 2 ) or greater.
  • This is a jet similar to that used in water jet cutting and orifice 23 may be made of for example synthetic sapphire.
  • jet 22 is slightly divergent when it issues from orifice 23. Abrasive particles are introduced into the entry 26 of nozzle 21.
  • the abrasive particles will normally have a random distribution of direction and velocity, but it is desirable to minimize the turbulence and to try to direct toward exit point 29.
  • the direction and velocity of the abrasive particles between points 27 and 28 in nozzle 21 still retains a random component and if jet 22 were allowed to leave at point 27 the cutting efficiency would be low.
  • the direction of the abrasive particles is oriented by jet 22 to ensure a predominant axial velocity, i.e.
  • abrasive particles are still moving much slower than jet 28, however, as time is required to transfer momentum from the relatively light liquid to the denser particles of abrasive. Accordingly, a section of nozzle 21 from point 28 to point 29 must be provided. The length of the section between point 28 and 29 must be sufficient so that the velocity of the particles entrained approaches that of jet 22 where point 29 is reached. If nozzle 21 is lengthened beyond point 29, frictional losses will occur resulting in deceleration of abrasive particle velocity and loss of cutting power.
  • a boundary layer of relatively low' velocity and lowered abrasive particle population allows an extended nozzle life and also can allow the area of nozzle 21 between points 28 and 29 to be made of relatively inexpensive material.
  • Prior designs have allowed the jet to leave the nozzle before concentration of particles in the centre of the jet and have produce high wear rates.
  • nozzle 22 must be sufficiently long for the abrasives to accelerate to at least 80% of the speed of jet 22 and to have a direction nearly parallel to the tube wall in order to provide a coherent and nearly parallel, cohesive, abrasive jet at point 29.
  • the diameter of the section between points 27 and 29 should be sufficiently small so that the abrasive particles are forced to remain in contact with the liquid, but large enough to pass the abrasives and the liquid. Tubes as small as 1.52 mm.
  • the length of nozzle 22 between points 27 and 29 should be between 25 to 100 times its diameter.
  • the diameter of this section should be at least 1.1 times the diameter of the abrasive particles (D ⁇ 1.1 dp).
  • the diameter of this section should be between 1.1 and 10 times the diameter of orifice 23 (10 dj ⁇ di; 1.1 dj). This requires, for example, a nozzle length between point 27 and 29 of at least 10 cm. for an orifice 23 of diameter more than or equal to 0.89 mm.
  • a 5 cm., or larger, tube is needed for a 0.51 mm, or larger orifice 23.
  • the length of the nozzle between points 27 and 29 must be at least 12.7 mm.
  • the section of nozzle 21 between points 28 and 29 may be made of the material having a knoop hardness over 1000 which includes carbides, ceramics, and similar materials.
  • the upper section of nozzle 21 between points 26 and 28 should be thick walled so that the abrasive particles can erode the inlet section between points 26 and 27 into a nozzle inlet shape.
  • Figure 5 shows a nozzle incorporating the invention.
  • High pressure liquid enters via a supply tube 31 from a high pressure intensifier (not shown).
  • Supply tube 31 is attached to the nozzle body 32 by means of a gland 33 and collar 34, although any other connector appropriate for the pressures used could be substituted.
  • the high pressure fluid then flows down the interior of nozzle body 32 which is closed at the end opposite supply tube 31 by a jewel holder 36.
  • jewel holder 36 is sealed to nozzle body 32 and includes a recess containing a jewel orifice 37.
  • jewel orifice 37 is constructed of a hard material for example synthetic sapphire having an orifice diameter of 0.025 mm. to 1.27 mm. and is similar to jewels used in high pressure water jet cutting.
  • Nozzle holder 39 includes a threaded attachment point 41 for nozzle body 32 and an introduction port 42 for particles of abrasive.
  • the particles of abrasive flow down a line (notshown) attached to port 42 from a storage tank (not shown).
  • Jet 38 and the abrasive particles then pass through a collar 43 in the interior of nozzle holder 39.
  • Collar 43 prevents erosive wear of nozzle holder 39.
  • the particles of abrasive and jet 38 then enter a tapered sleeve 44 before entering a nozzle 46.
  • Nozzle 46 is constructed of carbide, other hard material, and isfrom 51 to 200 mm.
  • Nozzle 46 is attached to a steel adaptor 47 by a compression fitting nut 48 and compression fitting sleeve 49.
  • Adaptor 47 is threadedly connected to nozzle holder 39, although equivalent attachment means could be used.
  • Collar 43, tapered sleeve 44 and the upper portion of nozzle 46 form the mixing chamber of the device.
  • the abrasive loaded stream 50 of liquid finally emerges at the end 51 of nozzle 46 and may be used for cutting such hard materials as steel or glass.
  • FIG. 6 is a block diagram of the method of the invention.
  • a high velocity water jet is generated 61. This may be done much as is presently done in water jet cutting.
  • Abrasive particles are then introduced with the stream 62 into an orienting tube. The particles are then orientated 63 into the direction of the stream.
  • Time is next allowed for acceleration of the particles 64 to a sizeable fraction of stream velocity. The acceleration is accomplished by forcing the stream into an additional length to assume a pipe flow where a boundary layer of fluid having reduced velocity causes concentration of particles in the centre of the jet.
  • the jet charged with particles exits 65 to do work.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
  • Disintegrating Or Milling (AREA)
  • Polishing Bodies And Polishing Tools (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
  • Laser Beam Processing (AREA)
  • Grinding-Machine Dressing And Accessory Apparatuses (AREA)
EP83306212A 1982-10-22 1983-10-13 High velocity fluid abrasive jet Expired EP0110529B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83306212T ATE46846T1 (de) 1982-10-22 1983-10-13 Fluessigkeitsschleuderstrahl mit grosser geschwindigkeit.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US43600282A 1982-10-22 1982-10-22
US436002 1995-05-05

Publications (3)

Publication Number Publication Date
EP0110529A2 EP0110529A2 (en) 1984-06-13
EP0110529A3 EP0110529A3 (en) 1985-10-16
EP0110529B1 true EP0110529B1 (en) 1989-10-04

Family

ID=23730692

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83306212A Expired EP0110529B1 (en) 1982-10-22 1983-10-13 High velocity fluid abrasive jet

Country Status (8)

Country Link
EP (1) EP0110529B1 (ja)
JP (2) JPS59134664A (ja)
AT (1) ATE46846T1 (ja)
AU (1) AU566151B2 (ja)
CA (1) CA1231235A (ja)
DE (1) DE3380663D1 (ja)
NO (1) NO159580C (ja)
ZA (1) ZA837483B (ja)

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8510538D0 (en) * 1985-04-25 1985-05-30 British Hydromechanics Nozzle
FR2584641B1 (fr) * 1985-07-12 1989-04-21 Assistance Prestations Dispositif de marquage
US4817874A (en) * 1985-10-31 1989-04-04 Flow Systems, Inc. Nozzle attachment for abrasive fluid-jet cutting systems
JPS6350699U (ja) * 1986-09-18 1988-04-06
KR930008692B1 (ko) * 1986-02-20 1993-09-13 가와사끼 쥬고교 가부시기가이샤 어브레시브 워터 제트 절단방법 및 장치
JPS6339243A (ja) * 1986-08-04 1988-02-19 Canon Inc 通信装置
US4854091A (en) * 1987-11-16 1989-08-08 Flow Industries, Inc. Abrasive swivel assembly and method
JPH0613840Y2 (ja) * 1988-02-09 1994-04-13 株式会社スギノマシン アブレーシブ供給装置
DE3844344A1 (de) * 1988-12-30 1990-07-12 Geesthacht Gkss Forschung Verfahren und vorrichtung zum schneiden und reinigen von gegenstaenden, sowie zum gezielten materialabtrag mittels eines wasser-abrasivmittel-gemisches
EP0445103A3 (en) * 1990-02-27 1992-10-21 Boehler Gesellschaft M.B.H. Method and device for feeding particles to an abrasive cutting device
FR2685027B1 (fr) * 1991-12-11 1994-04-01 Christian Diat Procede mecanique de nettoyage de la pollution des pierres de facade.
DK0616564T3 (ja) * 1991-12-11 1997-03-17 Christian Diat
DE4225590C2 (de) * 1992-08-03 1995-04-27 Johann Szuecs Vorrichtung für die Behandlung von empfindlichen Oberflächen, insbesondere von Skulpturen
TR28484A (tr) * 1993-10-27 1996-09-02 Johann Szucs Hassas yüzeylerin,özellikle heykellerin muamele edilmesine mahsus tertibat ve usul.
DE19640921C1 (de) * 1996-10-04 1997-11-27 Saechsische Werkzeug Und Sonde Modularer Abrasivmittelwasserstrahl-Schneidkopf
US5851139A (en) * 1997-02-04 1998-12-22 Jet Edge Division Of Tc/American Monorail, Inc. Cutting head for a water jet cutting assembly
FR2783735B1 (fr) * 1998-09-29 2000-12-15 Patrick Loubeyre Dispositif pour la decontamination des surfaces au moyen d'un jet compose d'air, d'une matiere de projection a grains fins et d'un liquide
US7067031B2 (en) 2003-12-03 2006-06-27 Dew Engineering And Development Limited Process for making a ceramic armor plate
CN102672625B (zh) * 2011-03-17 2016-12-14 新东工业株式会社 喷丸加工用喷嘴以及具备该喷嘴的喷丸加工装置
US9587298B2 (en) 2013-02-19 2017-03-07 Arconic Inc. Heat treatable aluminum alloys having magnesium and zinc and methods for producing the same
US10427752B2 (en) 2016-05-23 2019-10-01 Shimano Inc. Bicycle operating device
CN114033413A (zh) * 2021-11-09 2022-02-11 中铁工程装备集团有限公司 一种超声波辅助的高压水射流混合磨料喷头和掘进机

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE494888C (de) * 1928-08-31 1930-03-29 Alfred Gutmann A G Fuer Maschb Ringspaltduese fuer Sandstrahlgeblaese
US2176577A (en) * 1937-04-03 1939-10-17 Hydroblast Corp Sandblast device
FR1203550A (fr) * 1958-03-03 1960-01-19 Inst Rech S De La Sid Erurgie Dispositif pour communiquer des vitesses élevées à des particules en suspension dans un gaz
CH400811A (fr) * 1963-06-17 1965-10-15 Carpenter Leandre Pistolet de sablage
DE1477991A1 (de) * 1965-05-31 1969-07-17 Elektro Veb Vorrichtung zum Strahllaeppen
JPS5077987A (ja) * 1973-11-13 1975-06-25
US3994097A (en) * 1975-04-07 1976-11-30 Lamb Ralph W Abrasive or sand blast apparatus and method
FR2348751A1 (fr) * 1976-04-20 1977-11-18 Inst Tsementnoi Promy Injecteur pour appareils a jet
DE2648445A1 (de) * 1976-10-26 1978-04-27 Myers Europ Gmbh Flachstrahler fuer ein gemisch einer druckfluessigkeit mit feststoffteilchen
DE2724318C2 (de) * 1977-05-28 1984-09-20 Ernst Peiniger GmbH Unternehmen für Bautenschutz, 4300 Essen Verfahren zum Befeuchten des Strahlmittels beim Druckluftstrahlen
DE2928698A1 (de) * 1979-07-16 1981-02-19 Nat Res Dev Vorrichtung zur erzeugung eines mit schleifmittelteilchen versetzten fluessigkeitsstrahles (dispenser)
DE3127013A1 (de) * 1981-07-09 1983-01-27 Ernst Peiniger GmbH Unternehmen für Bautenschutz, 5090 Leverkusen Verfahren zum druckluftstrahlen und strahlgeraet zur durchfuehrung des verfahrens
FR2523019B1 (fr) * 1982-03-15 1985-11-08 Commissariat Energie Atomique Buse de sablage a jet plat et contenant des particules solides abrasives, et procede de mise en oeuvre d'une buse de sablage pour la decontamination radioactive

Also Published As

Publication number Publication date
DE3380663D1 (en) 1989-11-09
NO159580C (no) 1989-01-18
AU566151B2 (en) 1987-10-08
EP0110529A2 (en) 1984-06-13
ZA837483B (en) 1984-11-28
NO159580B (no) 1988-10-10
EP0110529A3 (en) 1985-10-16
CA1231235A (en) 1988-01-12
NO833847L (no) 1984-04-24
JPH0344452Y2 (ja) 1991-09-18
JPH01114267U (ja) 1989-08-01
ATE46846T1 (de) 1989-10-15
JPS59134664A (ja) 1984-08-02
AU1997883A (en) 1984-05-03

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