Automated abrasive water jet pin cutting system – mark II

Project Overview Automated abrasive water jet pin cutting system – mark II

Introduction: Technology Water jetcutting • Well known technology (state of the art) • developed in 1974 by Flow Industries • used for job shops, cutting metal sheets • Pure high-pressure water jets (200MPa) • cutting soft materials like paper, textiles foam and food • Abrasive water jets (up to 600MPa) • abrasive added to the pure water jet in a mixing chamber • particles are accelerated by the jet in a focusing tube • cutting of technical material like metals, plastics, glass, concrete and composites Cutting aluminum sheets by abrasive water jet cutting (AWJ) Waterjet Technologies AG

Introduction: Application Basic conditions • Blade fixation: • Finger root profile • locked by pins • Rotor geometry: • diameter: 0.5m-2m (without blades) • gap width: 50mm-400mm • Pin geometry: • diameter: 3mm-20mm • length: 30mm-400mm • Pin material: • steel or nickel based alloy Pins Pin-root steam turbine blades Waterjet Technologies AG

Introduction: Application Situation today • Procedure: • Most of the pins are pushed out with a hydraulic jack • Difficult pins (10%) are drilled out by special drilling systems • Problems: • High risk of damaging the disc drilling the pins • Tools are not mobile and the set-up time is long. Drilling machine Wandered drill Waterjet Technologies AG

Basic Developments Water jet cutting tool (2) • Standard Version : • 100mm length • standard consumables • cut width 0.8mm • Tool parts: • tool body • water supply • abrasive supply • water nozzle • mixing chamber • focusing tube (3) (1) (6) (5) (4) sectional drawing cutting tool Waterjet Technologies AG

Basic Developments Water jet catcher Main function: • consists of tungsten carbide bars stacked in a casing • absorbs remaining energy of the exiting water jet • avoids damage to next disc Process function: • detects breakthrough of jet during piercing by means of a accelration sensor • function of catcher is monitored water jet catcher (patent pending) Waterjet Technologies AG

Schematical Set-up Supplies High pressure pump Water treatment system Water supply (drinking water) Cutting head Abrasive doser Abrasive Tank Jet catcher Suction system Waste Waterjet Technologies AG

Pin Cutting Device – Mark II Robotics (2) (3) Device concept • Control unit • Human machine Interface (HMI) • Abrasive doser • Geometrical adjustment device • Cutting unit including cutting tool, camera and 2 linear axis • Catcher • Mobile device (1) (5) (4) (6) (7) PinCutter Mark II device Waterjet Technologies AG

Pin Cutting Device – Mark II Robotics Safety concept: Catcher • Safety function 1: Catcher tool including safety system to detect any malfunction: • Acceleration (1.1) sensor detects break-through of the jet during piercing • 2 inductive proximity (1.2) switches detects if the catcher is mounted on the rotor • 1 security switch (1.3) detects if the catcher is mounted properly on the device (1.2) (1.1) (1.3) (1.2) Catcher and Cutting unit Waterjet Technologies AG

Pin Cutting Device – Mark II (2) Robotics Safety concept: Cutting unit • Safety function (2): Safety system for detection of failure of clamping mechanism. • Safety function (3): Monitoring of the clamping mechanism of the cutting device by 2 inductive proximity switches and 2 force sensors. • Safety function (4): Monitoring of the tool fixture (tool mounted or not) by 1 safety switch (4) (3) (3) (2) Catcher and Cutting unit Waterjet Technologies AG

Pin cutting procedure Set up robotics next to the steam turbine System fixation with clamping mechanism Set pin position using camera tool 1 2 3 4 Parameters for piercing and cutting given by control: 5 Piercing a hole in the centre of the pin, cutting of rivet head 6 Cutting the pattern Distances Abrasive quantity Velocity Waterjet Technologies AG

Field Tests La Courneuve 2010 Initial situation • Rotor from le Havre (coast) • Heavy corroded and deformed pins • 6 blades with 3 pins each had to be removed • Drilling trials failed and caused heavy damage to the rotor • 12 remaining pins had to be removed by PinCutterMarkII • Rotor placed on gantry stands in the workshop System set-up in the workshop Waterjet Technologies AG

Field Tests La Courneuve 2010 General test results • First application was successful • 12 pins could be removed • Damage 4 times less then by drilling • Process time about 1hour per pin • Slight damage to the rotor • Jacking tools need to be improved Disc with removed pins Waterjet Technologies AG

Field Tests Berlin 2012 Initial situation • Test run to verify and compare the PinCutter Mark II • Scrap rotor out of the Kosovo • Unusual rotor condition, no pin could be pressed out by jacking • Rotor placed on gantry stands in the workshop • Test on disc L-0 (290mm pin length) and L-1 (190mm pin length) System set-up in the workshop Waterjet Technologies AG

Field Tests Berlin 2012 General test results • Pins of length 190mm and 290 (from 2 sides) were cut • Set-up time 4hours (1 operator) Disc L-1 results • 2 of 4 pins could be removed after cutting • Process time about 1hour per pin • Slight damage to the rotor • Jacking tools need to be improved Waterjet Technologies AG

Field Tests Berlin 2012 Disc L-0 results • Pins of length 290mm were cut from 2 sides • Prove of new cutting procedure (“line cut”) • 2 of 3 pins could be removed after cutting • Process time about 1hour per pin • Slight damage to the rotor pin cut by “line cut” procedure Waterjet Technologies AG

Actual project state Processcomparison Waterjet Technologies AG

Automated abrasive water jet pin cutting system – mark II