Optical Alignment Services
Introduction
Optical Alignment involves the use of high-precision telescopes & theodolites, similar to a surveyor’s transit, to measure machinery position & movement. We have over 30 years of optical alignment experience focusing on applications in power generation, oil & gas, and pulp & paper industries.
Is it Straight, Plumb, Square & Flat?
Using precision instruments from Brunson, Keuffel & Esser, Wild, and others, we can measure nearly anything with an accuracy & repeatability of 1 arc-second (that’s 0.001″ over 17 feet of sight!).
For a more detailed discussion, you can view our on-line presentation “Optical Alignment, Thermal Growth and Machinery Movement” on our Downloads page.
Courtesy: Brunson
Machinery Installation & Setup
When installing new or refurbished machinery, or undergoing significant repairs, M&B can assist you with a variety of tasks to get your work done on time and with a focus on ensuring long-term machinery reliability and operability. Some areas to focus on include:
- Check or set machinery sole plates level within +/- 0.001″
- Inspect the level condition of machine casings & split-lines
- Set bearing elevations & diaphragm bores
- Monitor long-term elevations of installed foundations for settling
We also have standard construction / surveying instrumentation and experience, to assist you with:
- Foundation layout
- Marking / checking hold-down bolt locations before pouring
- Elevation & grade studies
Thermal Growth Studies
Accurately measuring the movement of machinery and bearings that occurs from off-line to full-load operating conditions (offline-to-running, or ‘OL2R’) is critical to achieving accurate machinery alignment while operating. There is little point in setting a cold shaft alignment within 0.002″, if adjacent bearing housings move 10 or more times that amount in different directions!
Many customers ask us “Shouldn’t we just use the OEM thermal growth numbers?” While these provide a starting point, our field experience has proved that each machine will demonstrate unique responses. Until a particular machine is actually measured, you cannot be sure. We have repeatedly found the true “thermal growth” of most machinery does not match OEM values, and often is counter intuitive to assumed values. These discrepancies create misalignment while operating, and add mechanical stresses that reduce reliability and increase maintenance costs.
The discrepancies arise for two primary reasons. First, OEM values typically rely on an estimated delta-T across a bearing or support structure, to calculate a thermal expansion for each affected material. Any difference between estimated and actual material temperatures results in calculation errors. Also, even if temperatures are checked, they are only the ‘skin’ temperatures of the components, not the core temperatures, which can be significantly different. Second, and perhaps more significantly, calculated values cannot accurately account for the deflections incurred in the bearing housings, supports, casings, etc., that occur when a machine is under full operating torque, all of which directly affect the operating alignment of the machinery.
How can we provide you with accurate measurement of data that even the OEMs don’t seem to have?
Our engineers have 30+ years of experience using optical tooling & techniques to measure position changes due to thermal, torsional, and load related effects. Once this “thermal growth” is measured, we can offset the cold alignment to produce an Excellent alignment while operating. Our typical ‘thermal growth study’ measures the vertical and horizontal deflections of each bearing housing in a machine train. All measurements are referenced to common benchmarks mounted in the machinery foundation. Thus all bearings can be cross-referenced, ensuring an accurate overall alignment. This becomes particularly important on large turbo-machinery with several machine cases and long bearing spans.
Roll & Paper Machinery
Optical alignment is directly used in measuring the relative alignment of roll & paper / web handling machinery. It does not matter what type of roll equipment you are working with – paper machines, calenders, dryers, winders, web press printers, corrugators, coaters, laminators, fourdriniers or film extruders – we can provide you with the alignment services to keep you equipment running smoother and faster.
M&B engineers have extensive alignment experience on nearly every class of machine. We can identify and help you quickly correct existing problems caused by misalignment, and problems related to foundations, baseplates and piping. We can also provide your staff with specialized alignment training to improve their skills and increase your reliability.
We can assist you with nearly every phase of your machinery alignment measurements. And as always, our focus is on your long term reliability and operability. If you have questions, or an application that is not mentioned above, please call us to discuss your needs.
Some specific machinery we have worked with include:
- Compressors
- Boiler & Process Fans
- Cooling tower fans
- Vertical & Horizontal Pumps
- Reciprocating Engines
- Gearboxes
- Pulverizers & Ball Mills
- Steam Turbines up to 1200 MW
- Gas Turbines, aero-derivative & industrial frame
- Generators and Exciters
- Induction & Synchronous Motors
- Variable Frequency Drives
- Vertical & Horizontal Pumps
- Hydro-Turbine Generators
- Reciprocating Engines