US3737249A - High flow pump impeller for low net positive suction head and method of designing same - Google Patents
High flow pump impeller for low net positive suction head and method of designing same Download PDFInfo
- Publication number
- US3737249A US3737249A US00067131A US3737249DA US3737249A US 3737249 A US3737249 A US 3737249A US 00067131 A US00067131 A US 00067131A US 3737249D A US3737249D A US 3737249DA US 3737249 A US3737249 A US 3737249A
- Authority
- US
- United States
- Prior art keywords
- impeller
- blade
- angle
- beta
- suction head
- 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 - Lifetime
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D3/00—Axial-flow pumps
- F04D3/02—Axial-flow pumps of screw type
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/18—Rotors
- F04D29/22—Rotors specially for centrifugal pumps
- F04D29/2261—Rotors specially for centrifugal pumps with special measures
- F04D29/2277—Rotors specially for centrifugal pumps with special measures for increasing NPSH or dealing with liquids near boiling-point
Definitions
- the sweep angle 'y is quite large, 3,226,031 12/1965 Holland ..416/176 being in the inlet region of the impeller typically 45 3,261,294 7/1966 Schofield et a1. ..416/176 X or or 3,644,056 2/1972 Wiselins 416/176 UX 1,132,775 3/1915 Hille ..416/177 2 Claims, 6 Drawing Figures T (DISCHARGE) FLOW PATENTEDJUH 5mm 3,737,249
- SHEET 10F 2 (DISCHARGE BLADE FLOW ELEMENTS (INLET FLOW) INTERSECTION OF BLADE TH STREAM SURFACE OF REVOLUTION STREAM SURFACE I INTERSECTION OF BLADE WITH CONICAL $URFACE NORMAL TO THE BLADE ELEMENTS l N VENI'UR.
- the velocity relationships for fluid entering an impeller are illustrated by the vector diagrams that can be drawn on planes tangent to concentric stream surfaces of revolution formed by the incoming flow.
- Such a diagram consists of the fluid absolute inlet velocity V and the impeller blade lineal speed U at the radius (from I the axis of rotation of the impeller) of the particular stream surface associated with the diagram in question.
- the velocity W relative to the rotating impeller completes the vector diagram and is disposed at the flow angle B with respect to U.
- the intersection of the impeller blade with this stream surface is set at an angle B from the peripheral (U-) direction.
- the blade angle B is usually equal or nearly equal to the flow angle B to enable the impeller to receive the incoming fluid properly.
- the value of B is directly associated with the rate at which fluid flows through the impeller because B increases as the absolute inlet velocity V increases.
- a blade element is defined as the intersection of the blade surface with a meridional plane section through the impeller; i.e., a plane section containing the axis of rotation. If in this meridional plane a line perpendicular to a blade element at a point to be investigated is rotated about the axis of rotation, it will generate a conical surface of revolution to which the blade element is perpendicular. It has been found that the angle B between the intersection of the blade with this conical surface and the peripheral (U-) direction must be sufficiently small to insure successful pumping at low net positive suction head.
- Vi is the component of V projected onto the plane in which B lies, and since the two aforesaid planes are disposed from each other at the sweep angle y the flow angle Bi will be smaller than B for y a 0.
- the blade angles B and B are disposed from each other at the sweep angle y a 0.
- an impeller of a pump for a low net positive suction head application is provided and maintains the desired low blade angle while at the same time increasing volume flow rate capabilities over those otherwise obtainable at the same rotative speed and inlet diameter.
- FIG. 1 is a view of an impeller showing the velocity vectors at the inlet tip of the blade elements and the flow angles B and Bi. formed thereby;
- FIG. 2 is a view of a meridional (r-z) section through the impeller (i.e., a cross-section containing the axis of rotation) showing a forming step practiced in accordance with the principles of the present invention
- FIG. 3 is a view of the velocity vectors in a plane tangent to a stream surface of revolution along which the fluid flows through the impeller showing the blade angle B;
- FIG. 4 is a view of the velocity vectors in the plane tangent to a conical surface of revolution generated by revolving the line X perpendicular to the blade elements in the inlet region of the impeller (and therefore at sweep angle y to the stream surface) about the axis of rotation and shows the inlet blade setting angle B,, J. in this plane, which is smaller than B,,.
- FIG. 5 is a view of an impeller with forward swept blades incorporating the principles of the present invention.
- FIG. 6 is a fragmentary view of a helical impeller with swept back blades incorporating the principles of the present invention.
- This invention allows the impeller of an aircraft fuel booster pump or other pump for low net positive suction head to be capable of operating at higher maximum volume flow rates at both high and low net positive suction head conditions, corresponding respectively to sea level and climb conditions for an aircraft fuel booster pump, while at the same time restricting the impeller inlet and outlet diameters and rotative speed to the same values that produce the lower maximum flow rates of conventionally designed impellers.
- FIG. 1 of the drawings a velocity diagram for fluid entering a centrifugal impeller at the blade tips.
- the fluid absolute inlet velocity is V
- the impeller blade lineal speed is shown as U.
- the velocity W relative to the rotating impeller completes the vector diagram and it will be noted that the vector W is at an angle B with respect to U.
- the trace of an impeller blade on a fluid stream surface of revolution is set at the angle 3,, which is equal or nearly equal to the flow angle [3 to enable the impeller to receive the incoming fluid properly.
- conventional impellers running at maximum allowable tip speed U for receiving boiling fluid which, at a given rotative speed, corresponds to the largest possible impeller inlet diameter, cannot have conventional blades set at more than some limiting value of 3,, without impairing the ability of the impeller to pump the associated maximum possible flow rate of such boiling fluid.
- conventionally designed blades are set so that their elements, or their traces on the r-z cross-section plane, are perpendicular to the concentric stream surfaces of revolution whose traces on the r-z plane usually appear as z-directed axial lines in the inlet region of the impeller and as shown in this illustrative example.
- conventional blades have essentially radial elements in the inlet region.
- the blade elements in the inlet region of the impeller will be inclined at a sweep angle 7 of about 45 or more to their conventional setting, i.e., they are deliberately made not even nearly perpendicular to the stream surfaces of revolution containing V (FIG. 3) i.e., swept forward or backward.
- V FIG. 3
- FIG. 4 shows the projection of the velocity vector diagram of FIG. 3 into the plane perpendicular to the blade element.
- the flow angle Bi. will be smaller than [3 if the blade elements in the inlet region of the impeller are inclined at an angle 1 in accordance with this invention.
- the impeller is made or fabricated by conventional manufacturing techniques, however, the values of central angle 6 of each blade element are specified by the designer in accordance with this invention.
- a blade cutting tool is utilized and in the inlet region of the impeller the tool is disposed at a cutting angle y from the radial direction corresponding to the desired angle of the blade element from perpendicularity to the axially approaching flow velocity vector V.
- the inclination of the impeller blade elements in the inlet region of the impeller at an angle not even nearly perpendicular to the direction of the approaching fluid permits a corresponding increase of fluid volume flow rate over that of conventionally bladed impellers of equal inlet diameter operating at the same rotative speed.
- increases of attainable fluid volume flow rate are obtainable at both high and low net positive suction head conditions, for exam.- ple, sea level and boiling fuel conditions in an aircraft fuel booster pump application.
- FIGS. 5 and 6 there is illustrated in each of the respective views a helical impeller constructed in accordance with the principles of the present invention, FIG. 6 showing a helical impeller with swept back blades, i.e., blades having sweep in accordance with the angle 'y and Exhibit 5 showing a helical impeller with forwardly swept blades i.e., blades having a forward sweep in accordance with the angle y.
- the pertinent angles in relationships as well as the direction of fluid flow corresponding to those already identified in the drawings appear on both of the Figures.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
Description
Claims (2)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US6713170A | 1970-08-26 | 1970-08-26 |
Publications (1)
Publication Number | Publication Date |
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US3737249A true US3737249A (en) | 1973-06-05 |
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Family Applications (1)
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US00067131A Expired - Lifetime US3737249A (en) | 1970-08-26 | 1970-08-26 | High flow pump impeller for low net positive suction head and method of designing same |
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Cited By (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0011506A1 (en) * | 1978-11-17 | 1980-05-28 | Spp Group Limited | Single vane rotodynamic impeller |
US5108257A (en) * | 1989-05-26 | 1992-04-28 | Pacific Machinery & Engineering Co., Ltd. | Impeller for turbo pump for water jet propulsion machinery, and turbo pump including same impeller |
US5192193A (en) * | 1991-06-21 | 1993-03-09 | Ingersoll-Dresser Pump Company | Impeller for centrifugal pumps |
EP0764577A1 (en) * | 1995-04-28 | 1997-03-26 | Ishigaki Company Limited | Water jet propulsion machine for marine vessels |
WO2001009515A1 (en) * | 1999-07-29 | 2001-02-08 | Rosefsky Jonathan B | Ribbon drive pumping apparatus and method |
US6435829B1 (en) * | 2000-02-03 | 2002-08-20 | The Boeing Company | High suction performance and low cost inducer design blade geometry |
US6527520B2 (en) | 1999-07-29 | 2003-03-04 | Jonathan B. Rosefsky | Ribbon drive pumping with centrifugal contaminant removal |
US20040033142A1 (en) * | 1999-07-29 | 2004-02-19 | Rosefsky Jonathan B. | Ribbon drive pumping apparatus and method with added fluid |
US20110027076A1 (en) * | 2009-08-03 | 2011-02-03 | Ebara International Corporation | Counter Rotation Inducer Housing |
US20110027071A1 (en) * | 2009-08-03 | 2011-02-03 | Ebara International Corporation | Multi-stage inducer for centrifugal pumps |
CN102011748A (en) * | 2010-12-23 | 2011-04-13 | 江苏国泉泵业制造有限公司 | Design method for high-efficiency whirlpool pump impeller |
US20110123321A1 (en) * | 2009-08-03 | 2011-05-26 | Everett Russell Kilkenny | Inducer For Centrifugal Pump |
CN102588332A (en) * | 2012-03-08 | 2012-07-18 | 江苏大学 | Centrifugal impeller designing method of nuclear main pump |
CN102979759A (en) * | 2012-12-11 | 2013-03-20 | 江苏大学 | Design method for impeller of multiphase mixed transportation pump |
CN103573643A (en) * | 2013-11-07 | 2014-02-12 | 泾县双氟泵阀技术服务有限公司 | Novel plastic-lined centrifugal pump |
WO2014047619A2 (en) * | 2012-09-24 | 2014-03-27 | Chris Rorres | Methods and apparatus for moving fluid using a strake |
US8998582B2 (en) | 2010-11-15 | 2015-04-07 | Sundyne, Llc | Flow vector control for high speed centrifugal pumps |
US20170097008A1 (en) * | 2015-10-02 | 2017-04-06 | Sundyne, Llc | Low-Cavitation Impeller and Pump |
US9631622B2 (en) | 2009-10-09 | 2017-04-25 | Ebara International Corporation | Inducer for centrifugal pump |
TWI601885B (en) * | 2015-03-25 | 2017-10-11 | 林聖梁 | Guiding device for liquid rotating |
JP2018509558A (en) * | 2015-03-25 | 2018-04-05 | 林聖梁Lin, Sheng−Lian | Liquid rotation guide device |
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US28542A (en) * | 1860-05-29 | Etaeiue propeller | ||
US242842A (en) * | 1881-06-14 | Daniel euggles | ||
US323734A (en) * | 1885-08-04 | randall | ||
US1085949A (en) * | 1912-02-14 | 1914-02-03 | R J Beatty | Pump. |
US1088883A (en) * | 1913-05-20 | 1914-03-03 | Emil Imle | Screw-blade for impellers. |
US1132775A (en) * | 1913-11-11 | 1915-03-23 | Adolph W Hille | Rotatable inclined water and material lifting elevator. |
FR557189A (en) * | 1922-10-07 | 1923-08-04 | Water wheel | |
US1497665A (en) * | 1923-03-14 | 1924-06-10 | Kaplan Victor | Blade of rotor wheels |
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US1795588A (en) * | 1927-10-13 | 1931-03-10 | Goodrich Co B F | Impelling apparatus |
US1805359A (en) * | 1929-07-20 | 1931-05-12 | Polo Alfred De | Propeller |
FR758374A (en) * | 1932-05-21 | 1934-01-15 | Helical thruster | |
FR790685A (en) * | 1935-05-31 | 1935-11-25 | Spiral propeller | |
US2133853A (en) * | 1937-01-27 | 1938-10-18 | Feige Gustav | Propeller |
US2935246A (en) * | 1949-06-02 | 1960-05-03 | Onera (Off Nat Aerospatiale) | Shock wave compressors, especially for use in connection with continuous flow engines for aircraft |
US3023709A (en) * | 1958-05-26 | 1962-03-06 | Kondo Masukichi | Vanes of an impeller for axial flow propeller pumps |
US3082695A (en) * | 1959-06-15 | 1963-03-26 | Klein Schanzlin & Becker Ag | Impellers, especially single vane impellers for rotary pumps |
US3226031A (en) * | 1962-10-31 | 1965-12-28 | Jr Raymond Prunty Holland | Induction propeller |
US3261294A (en) * | 1963-11-08 | 1966-07-19 | Chandler Evans Inc | Contaminant separating fuel pump |
US3644056A (en) * | 1970-03-06 | 1972-02-22 | Koninkl Maschf Stork Nv | Centrifugal pump |
-
1970
- 1970-08-26 US US00067131A patent/US3737249A/en not_active Expired - Lifetime
Patent Citations (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US28542A (en) * | 1860-05-29 | Etaeiue propeller | ||
US242842A (en) * | 1881-06-14 | Daniel euggles | ||
US323734A (en) * | 1885-08-04 | randall | ||
US1085949A (en) * | 1912-02-14 | 1914-02-03 | R J Beatty | Pump. |
US1088883A (en) * | 1913-05-20 | 1914-03-03 | Emil Imle | Screw-blade for impellers. |
US1132775A (en) * | 1913-11-11 | 1915-03-23 | Adolph W Hille | Rotatable inclined water and material lifting elevator. |
FR557189A (en) * | 1922-10-07 | 1923-08-04 | Water wheel | |
US1497665A (en) * | 1923-03-14 | 1924-06-10 | Kaplan Victor | Blade of rotor wheels |
CH129162A (en) * | 1927-10-11 | 1928-12-01 | Eugen Ruf | Propeller. |
US1795588A (en) * | 1927-10-13 | 1931-03-10 | Goodrich Co B F | Impelling apparatus |
US1805359A (en) * | 1929-07-20 | 1931-05-12 | Polo Alfred De | Propeller |
FR758374A (en) * | 1932-05-21 | 1934-01-15 | Helical thruster | |
FR790685A (en) * | 1935-05-31 | 1935-11-25 | Spiral propeller | |
US2133853A (en) * | 1937-01-27 | 1938-10-18 | Feige Gustav | Propeller |
US2935246A (en) * | 1949-06-02 | 1960-05-03 | Onera (Off Nat Aerospatiale) | Shock wave compressors, especially for use in connection with continuous flow engines for aircraft |
US3023709A (en) * | 1958-05-26 | 1962-03-06 | Kondo Masukichi | Vanes of an impeller for axial flow propeller pumps |
US3082695A (en) * | 1959-06-15 | 1963-03-26 | Klein Schanzlin & Becker Ag | Impellers, especially single vane impellers for rotary pumps |
US3226031A (en) * | 1962-10-31 | 1965-12-28 | Jr Raymond Prunty Holland | Induction propeller |
US3261294A (en) * | 1963-11-08 | 1966-07-19 | Chandler Evans Inc | Contaminant separating fuel pump |
US3644056A (en) * | 1970-03-06 | 1972-02-22 | Koninkl Maschf Stork Nv | Centrifugal pump |
Cited By (33)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0011506A1 (en) * | 1978-11-17 | 1980-05-28 | Spp Group Limited | Single vane rotodynamic impeller |
WO1980001095A1 (en) * | 1978-11-17 | 1980-05-29 | G Lake | Single vane rotodynamic impeller |
US5108257A (en) * | 1989-05-26 | 1992-04-28 | Pacific Machinery & Engineering Co., Ltd. | Impeller for turbo pump for water jet propulsion machinery, and turbo pump including same impeller |
US5192193A (en) * | 1991-06-21 | 1993-03-09 | Ingersoll-Dresser Pump Company | Impeller for centrifugal pumps |
US5989083A (en) * | 1995-04-28 | 1999-11-23 | Ishigaki Company Limited | Water jet propulsion device for vessels |
EP0764577A4 (en) * | 1995-04-28 | 1999-06-09 | Ishigaki Mech Ind | Water jet propulsion machine for marine vessels |
EP0764577A1 (en) * | 1995-04-28 | 1997-03-26 | Ishigaki Company Limited | Water jet propulsion machine for marine vessels |
WO2001009515A1 (en) * | 1999-07-29 | 2001-02-08 | Rosefsky Jonathan B | Ribbon drive pumping apparatus and method |
US6357998B1 (en) | 1999-07-29 | 2002-03-19 | Jonathan B. Rosefsky | Ribbon drive pumping apparatus and method |
US6431926B1 (en) | 1999-07-29 | 2002-08-13 | Jonathan B. Rosefsky | Ribbon drive propulsion system and method |
US6527520B2 (en) | 1999-07-29 | 2003-03-04 | Jonathan B. Rosefsky | Ribbon drive pumping with centrifugal contaminant removal |
US6592335B2 (en) | 1999-07-29 | 2003-07-15 | Jonathan B. Rosefsky | Ribbon drive pumping apparatus and method |
US20040033142A1 (en) * | 1999-07-29 | 2004-02-19 | Rosefsky Jonathan B. | Ribbon drive pumping apparatus and method with added fluid |
US7018170B2 (en) | 1999-07-29 | 2006-03-28 | Rosefsky Jonathan B | Ribbon drive pumping apparatus and method with added fluid |
US6435829B1 (en) * | 2000-02-03 | 2002-08-20 | The Boeing Company | High suction performance and low cost inducer design blade geometry |
US20110027071A1 (en) * | 2009-08-03 | 2011-02-03 | Ebara International Corporation | Multi-stage inducer for centrifugal pumps |
US20110027076A1 (en) * | 2009-08-03 | 2011-02-03 | Ebara International Corporation | Counter Rotation Inducer Housing |
US20110123321A1 (en) * | 2009-08-03 | 2011-05-26 | Everett Russell Kilkenny | Inducer For Centrifugal Pump |
US8506236B2 (en) | 2009-08-03 | 2013-08-13 | Ebara International Corporation | Counter rotation inducer housing |
US8550771B2 (en) * | 2009-08-03 | 2013-10-08 | Ebara International Corporation | Inducer for centrifugal pump |
US9631622B2 (en) | 2009-10-09 | 2017-04-25 | Ebara International Corporation | Inducer for centrifugal pump |
US8998582B2 (en) | 2010-11-15 | 2015-04-07 | Sundyne, Llc | Flow vector control for high speed centrifugal pumps |
CN102011748A (en) * | 2010-12-23 | 2011-04-13 | 江苏国泉泵业制造有限公司 | Design method for high-efficiency whirlpool pump impeller |
CN102588332A (en) * | 2012-03-08 | 2012-07-18 | 江苏大学 | Centrifugal impeller designing method of nuclear main pump |
WO2014047619A2 (en) * | 2012-09-24 | 2014-03-27 | Chris Rorres | Methods and apparatus for moving fluid using a strake |
WO2014047619A3 (en) * | 2012-09-24 | 2015-07-16 | Chris Rorres | Methods and apparatus for moving fluid using a strake |
US10030627B2 (en) | 2012-09-24 | 2018-07-24 | Chris Rorres | Methods and apparatus for moving fluid using a strake |
CN102979759A (en) * | 2012-12-11 | 2013-03-20 | 江苏大学 | Design method for impeller of multiphase mixed transportation pump |
CN103573643A (en) * | 2013-11-07 | 2014-02-12 | 泾县双氟泵阀技术服务有限公司 | Novel plastic-lined centrifugal pump |
TWI601885B (en) * | 2015-03-25 | 2017-10-11 | 林聖梁 | Guiding device for liquid rotating |
JP2018509558A (en) * | 2015-03-25 | 2018-04-05 | 林聖梁Lin, Sheng−Lian | Liquid rotation guide device |
US20170097008A1 (en) * | 2015-10-02 | 2017-04-06 | Sundyne, Llc | Low-Cavitation Impeller and Pump |
US10001133B2 (en) * | 2015-10-02 | 2018-06-19 | Sundyne, Llc | Low-cavitation impeller and pump |
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Owner name: PRUDENTIAL INSURANCE COMPANY OF AMERICA, THE, Free format text: SECURITY INTEREST;ASSIGNOR:ARCO-TECH CORPORATION A CORP OF DE;REEL/FRAME:005437/0698 Effective date: 19900630 Owner name: AMERITRUST COMPANY NATIONAL ASSOCIATION Free format text: SECURITY INTEREST;ASSIGNOR:ARGO-TECH CORPORATION, A CORP. OF DE.;REEL/FRAME:005443/0153 Effective date: 19900630 |
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Owner name: ARGO-TECH CORPORATION, A CORP. OF DELAWARE Free format text: SECURITY INTEREST;ASSIGNOR:AMERITRUST COMPANY NATIONAL ASSOCIATION;REEL/FRAME:005576/0273 Effective date: 19901224 Owner name: ARGO-TECH CORPORATION, A CORP OF DE Free format text: RELEASED BY SECURED PARTY;ASSIGNOR:PRUDENTIAL INSURANCE COMPANY OF AMERICA, THE;REEL/FRAME:005559/0287 Effective date: 19901224 |