# US 12,000,302 B2 · Aircraft engine repair tool and method for removal and installation of a mid turbine frame in an aircraft engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,000,302 B2 - Document ID: US12000302B2 - Status: Granted - Kind: B2 - Application number: 18/197,209 - Filed: 2023-05-15 - Published: 2023-09-28 - Granted: 2024-06-04 - Earliest claimed: 2021-12-01 - Assignees: Pratt & Whitney Canada Corp. - Applicants: Pratt & Whitney Canada Corp. - Inventors: Carlo Porco; Geoffrey Henriksen; Jason Wedemire; Anthony Mathias; Michael Hunze; Louis Lavoie; Marven Paynter; Dennis Wilkinson - Web page: https://patentgrep.com/patent/US12000302B2 ## CPC - F01D 25/285: {Temporary support structures, e.g. for testing, assembling, installing, repairing; Assembly methods using such structures} - B64F 5/50: Handling or transporting aircraft components - F01D 25/24: Casings (modified for heating or cooling F01D25/14); Casing parts, e.g. diaphragms, casing fastenings (casings for rotary machines or engines in general F16M {; special arrangements in stators dealing with breaking-off of part of rotor F01D21/045}) - F05D 2220/323: for aircraft propulsion, e.g. jet engines - F05D 2230/60: Assembly methods - F05D 2230/644: for adjusting the position or the alignment, e.g. wedges or eccenters - F05D 2230/68: using auxiliary equipment for lifting or holding - F05D 2230/70: Disassembly methods - F05D 2230/72: Maintenance - F05D 2230/80: Repairing, retrofitting or upgrading methods - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - B64F: GROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT; DESIGNING, MANUFACTURING, ASSEMBLING, CLEANING, MAINTAINING OR REPAIRING AIRCRAFT, NOT OTHERWISE PROVIDED FOR; HANDLING, TRANSPORTING, TESTING OR INSPECTING AIRCRAFT COMPONENTS, NOT OTHERWISE PROVIDED FOR - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract An aircraft engine repair tool for installing and/or removing a mid turbine frame from a gas turbine engine is provided. The tool includes a stabilizer configured to support a shaft via a load path different from a load path provided by the mid turbine frame rotatably supporting the shaft about a rotation axis. The tool includes a holder attachable to the mid turbine frame, and a guide movably engageable with the shaft and attachable to the holder. The guide guides movement of the holder and of the mid turbine frame relative to the shaft along the rotation axis, and prevents movement of the holder and the mid turbine frame relative to the shaft transverse to the rotation axis when the mid turbine frame is released from the support structure and attached to the holder, and when the holder is attached to the guide. ## Claims ### Claim 1 A method for installing a mid turbine frame on a gas turbine engine, or removing the mid turbine frame from the gas turbine engine, the mid turbine frame being located between a first turbine rotor and a second turbine rotor in a turbine section of the gas turbine engine during operation of the gas turbine engine, the mid turbine frame rotatably supporting a shaft about a rotation axis and defining a first load path between the shaft and a support structure of the gas turbine engine, the second turbine rotor being uninstalled from the gas turbine engine and the shaft supporting the first turbine rotor, the method comprising: supporting the shaft on a second load path between the shaft and the support structure of the gas turbine engine, the second load path being different from the first load path; movably engaging the shaft with a guide and attaching the guide to a holder to permit movement of the holder relative to the shaft along the rotation axis and prevent movement of the holder relative to the shaft transverse to the rotation axis; with the mid turbine frame attached to the holder and the mid turbine frame released from the support structure of the gas turbine engine, moving the holder and the mid turbine frame together along the rotation axis toward or away from an installed position of the mid turbine frame in the support structure; and after moving the holder and the mid turbine frame along the rotation axis, either: attaching the mid turbine frame to the support structure when the holder and the mid turbine frame have been moved toward the installed position of the mid turbine frame; or releasing the mid turbine frame from the support structure when the holder and the mid turbine frame have been moved away from the installed position of the mid turbine frame. ### Claim 2 (depends on 1) The method as defined in claim 1, wherein supporting the shaft comprises: inserting an arm in a bore of the shaft; attaching a base to the support structure of the gas turbine engine, the arm being pivotally coupled to the base about a pivot axis; pivoting the arm relative to the base about the pivot axis; and engaging the arm with the shaft. ### Claim 3 (depends on 2) The method as defined in claim 2, wherein: the gas turbine engine is a turbofan gas turbine engine; and the arm is inserted in the bore of the shaft via a forward end of the shaft. ### Claim 4 (depends on 2) The method as defined in claim 2, further comprising measuring at least one of a vertical and a horizontal movement of the shaft when the shaft is engaged by the arm and the arm is pivoted about the pivot axis. ### Claim 5 (depends on 1) The method as defined in claim 1, comprising supporting the shaft via a support pin extending between the support structure and a compressor rotor of the gas turbine engine supported by the shaft. ### Claim 6 (depends on 1) The method as defined in claim 1, comprising supporting the shaft via a shim disposed between the first turbine rotor and the support structure of the gas turbine engine. ### Claim 7 (depends on 1) The method as defined in claim 1, wherein the guide includes an insert slidably inserted into the shaft.