Transcript Document
WELCOME TO Alignment Techniques – Traditional, Optical, Digital Warren Wagstaff – Digital Precision Metrology Inc. October 2014 Or just making it better? Alignment tools Traditional Tools - Plumb bobs - Precision Levels - Straight edges - Piano wire - Wire mics - Tape Measures Traditional Tools - Pros - Used since the Egyptians - Proven methods - Inexpensive - Reliable (can always go back to it) - Keeps people working - Comfort (widely accepted) Traditional Tools - Cons - Labour intensive - Opinion / feel - Human error - Resolution - Accuracy - Repeatability - Susceptible to drift - Wire sag in horizontal applications Optical Tools - Optical Transits - Scales - Precision Levels (standard and optic) - Targets - Laser tools Optical Tools - Pros - Accurate - Comfort (people accept it) - Portable - Relatively inexpensive Optical Tools - Cons - Labour intensive - Susceptible to environmental conditions (lighting, dust, heat, vibrations) - Allows for human error (transposing numbers) - LOS (line of sight) - Not easily moved and tied in (device move) - Fragile Digital Tools - CMM (coordinate measuring machines) - Laser Trackers - Arms - SMR’s (spherically mounted retroreflectors) - Probes - Target holders Digital Tools – Cont’d CMM (coordinate measuring machine) A coordinate measuring machine (CMM) is a device for measuring the physical geometrical characteristics of an object. This machine may be manually controlled by an operator or it may be computer controlled. Measurements are defined by a probe attached to the third moving axis of this machine. Probes may be mechanical, optical, laser, or white light, amongst others. A machine which takes readings in six degrees of freedom and displays these readings in mathematical form is known as a CMM. http://en.wikipedia.org/wiki/Coordinate_measuring_machine Digital Tools - Pros - Accuracy (0.0004” over 24’) - Fast (real-time) - 3D data (XYZ coords) - Adapts to environment - Data digitally recorded - Can easily be moved and tied in (check drift) - Allows for GD&T Measurements (flatness, concentricity, roundness, parallelism, etc.) Digital Tools - Cons - Expensive (unit and tooling) - Expensive software - LOS (line of sight – Laser Tracker) - Warm-up or acclimatization time - Requires a skilled operator So how can new technology help? Why Laser Trackers? • It’s Todays Technology • Laser beams don’t sag, not affected by gravity • Not effected by shaft run-out or eccentricity • Can Monitor distance travelled over time (troubleshooting) • Built in temperature compensation (weather station – pressure, temp, humidity) • Traceability to NIST (National Institute for Standards and Technology) • Calibrated and certified to accuracies stated • Provide XYZ coordinates and/or deviations in real-time Setting a bedframe for a turbine 84% savings just on one part of the project!! Let alone project completion time!! Less chance of safety incidents due to man hours!!! ETC. Cost Benefits of taking a leap of faith - Time --- up to 14x faster than traditional methods when setting bases or doing new builds/layouts (setting turbine bases, cases, rotors, etc.) and less manpower required - Time --- up to 3x faster than optical methods on new builds/layouts Where Traditional and Optical Tools Trump CMM’s - Tight spaces - Smaller applications (shaft coupling) - Low accuracy requirements Where Digital Trumps Optical and Traditional - Building or aligning to CAD/drawings - Field machining, verification of flatness and/or machined heights to drawings (pump and motor base plates/sole plates) - Alignment of shafts that are cumulative or through walls - Verification of gear case alignments, sheave alignments - New builds - Mapping existing conditions of parts Benefits of a good alignment 1. Less fatigue on parts 2. Potentially can increase the speed of the machine 3. Potentially reduce frequency of alignment www www.digitalprecision.ca Conventional Alignment Clamps, straight edges & Indicators; Time consuming No hard copy available Labour intensive Costly www.digitalprecision.ca Vertical Alignment Four wire method; costly? slow tedious process? difficult to use? Inclinometer; digital with output? Optical; limited to distance or range? Strategies Roll Measurement as 2 circles Circularity – Point collection Cylinder method – Scanning of Rolls Tangent method – High points of Rolls Important Drift Check – Has anything moved? Contributors Sunlight Vibration Truck traffic Laser Tracker Increased quality of alignment Increased speed of machine Reduced frequency of alignment Greater speed of alignment Shorter shutdowns To summarize Benefits of using new technology • Speed, Accuracy and Traceability • Up to 3x as fast as an Optical system • Data and reports saved automatically, leaves a digital footprint • • Export in Excel, PDF, CSV, or to CAD. Consistent error free process Warren Wagstaff – Consultant – 3D Metrology Digital Precision Metrology Inc. Ph: 778-833-3276 Email: [email protected]