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

2. Cutting aluminum sheets by abrasive water jet cutting (AWJ)
Introduction: Technology
Water jet cutting
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

3. Pin-root steam turbine blades
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

4. 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

5. sectional drawing cutting tool
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

6. water jet catcher (patent pending)
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

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

8. PinCutter Mark II device
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

9. Catcher and Cutting unit
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

10. Catcher and Cutting unit
Pin Cutting Device – Mark II
Robotics
(2)
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

11. Parameters for piercing and cutting given by control:
Pin cutting procedure 1
Set up robotics next to
the steam turbine 2
System fixation with
clamping mechanism 3
Set pin position using
camera tool 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

12. System set-up in the workshop
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 PinCutter MarkII
Rotor placed on gantry stands in the workshop
System set-up in the workshop
Waterjet Technologies AG

13. 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

14. System set-up in the workshop
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

15. Field Tests Berlin 2012 General test results Disc L-1 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

16. pin cut by “line cut” procedure
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

17. integrated in the gantry stands
Actual project state
Process comparison
PinCutter Mark II
Drilling machine
Set-up time
4 hours
integrated in the gantry stands
Operator
1 trained operator
2 trained operators
Process time L-1
Removal rate
1 hour
2 of 4
6 hours
0 of1
Process time L-0
2 of 3
8 hour
0 of 1
Borehole damage
less than 1mm
up to 4mm
Waterjet Technologies AG