Shaft align1 requirements apply as the basic criteria. The alignment of turbinegenerator sets poses unique challenges that only the best laser shaft alignment systems can overcome. Alignment procedure an executable part of the alignment process where alignment is performed in accordance with the defined requirements. Nov 04, 2010 many consider runninggear alignment to be a black art. Shaft misalignment is responsible for as much as 50 percent of. The proper shaft alignment procedure is to secure the. A practical guide to pulley alignment plant services. After removing the cardan shaft the special offset fixture mounts across the coupling flange of the driven machine. Thanks to flexible brackets you can install the equipment in the most appropriate place.
This paper describes procedures for installation and alignment of propulsion shafting using bearing reaction methods, with emphasis on the shipboard work required. Proper shaft alignment is required to maintain operational longevity of all rotating machinery. Recent experience reflects concerns on propeller shaft aft bearing performance on some oil lubricated installations, e. How to do the alignment of shafts, compressors and. The fixturlaser xas and gos allow you the option to. Checking bearing alignment written by mt staff monday, 31 january 2000 08. Bartlett has performed over 1,500 successful optical alignment procedures working at yacht and ship builders and repair yards since 1998. For angular misalignments, a simple approach is as follows. Offset shaft alignments require specific shaft alignment equipment. The content of this infographic is a basic guide to realign machines. Shaft alignment definition most shipboard configurations of shafts and bearings are likely to be aligned when some or all of the centrelines of the bearings are offset from the theoretical straight line condition, so as to achieve an acceptable bearing load distribution and shaft slope. Lloyds register emeas technical investigations provides a comprehensive range of measurement and advisory services to help owners, operators and yards to help to ensure that the best. Propeller shaft alignment forward alignment approach. Shaft alignment industrial wiki odesie by tech transfer.
Alignment is critical to modem sawmills using thin kerf saws. Thats why the shaft alignment software was designed to help walk you through the stepbystep process of aligning your rotating machinery. Apr 15, 2015 after a quick horizontal correction the machine was placed in operation to heat it back up, afterwards a second hot alignment check indicated an excellent precision shaft alignment. Sighting through as part of shaft alignment procedure eliza jaryszkami ska west pomeranian university of technology, szczecin, institute of manufacturing engineering, al. To provide an overview of alignment, the discus sion in this. Apr 21, 2017 there is another side to the alignment story. Shaft alignment procedure pdf and guidelines for the implementation of good shaft alignment for standard rotating. Since using laser alignment equipment for many years,i have become a little rusty in using dial indicators for alignment of pumps etc. If, on the other hand, you update your knowledge of shaft alignment techniques and acceptable alignment tolerances, you might be on the way to becoming more reliabilityfocused. Special brackets are available for alignment with locked rotors to increases the safety of the operator. Service bulletin propeller gearbox alignment procedure description the alignment of your engine, engine mounting plate, and propeller gearbox is critical for a smooth running and long lasting gearbox. Ship shafting alignment procedure with offset of reference line. Shaft alignment is a method or procedure by which shafts of machines such as motors and turbines are connected to a generator or pump in proper alignment. Alternately, the races of aligned bearings are coaxial.
Modelling of propulsion shaft line and basic procedure of shafting alignment calculation article pdf available in brodogradnja 593. The procedure for determining whether the engine mounts are holding the engines steady is very simple, it is called the back down test. Shaft aligning procedure preliminary checks visually check coupling, pipe hangers, base bolts, coupling spacing etc. How shaft alignment tolerances must be expressed the only correct way to express shaft alignment tolerances is in terms of alignment conditions at the coupling, and we will describe several ways to do this. A guide to shaft alignment achieving a satisfactory shaft alignment is paramount for the safe and reliable operation of a ship during its lifetime. These were published as an integral part of the dnv gl merger and from the synergy derived. Research article shafting alignment computing method of new. Shaft aligning techniques shaft alignment by conventional method shaft alignment by dial test indicator dti shaft alignment by using laser equipment shaft alignment by using computer. Shaftalign os3 is easily extendable through the activation of powerful options as the alignment requirements grow. At a yard i once managed, i clearly recall watching a contractor, who specialized in this work, take a decidedly seatofthepants approach to calculating shaft weight and the associated sag or droop. Unit 1 pre alignment considerations pre alignment checks and corrections are performed to either improve machinery reliability or to facilitate the alignment process. The objective of optimized shaft alignment is to increase the operating life span of rotating machinery. Pdf modelling of propulsion shaft line and basic procedure.
Due to the design and construction of the drive shaft and universal joint assembly, the replace ment of any part or parts can be. To achieve our goal of proper shaft alignment, we must correct for both types of misalignment. Regarding john gross question about how a shaft can be aligned with so many things being so wobbly. If excessive run out is present on the shaft it may be bent and must be replaced before radial runout on the pulley is checked again. Both types can be found in the vertical and horizontal planes. Our vision is to build a digital community through websites, enewsletters, and social media channels that allows pump industry professionals to exchange ideas, news stories, product information, case studies, videos, event information and more.
Several equipment alignment methods, especially the reverse dial indicator method, which is the principle used in laser alignment is covered in explicit detail. Accurate shaft alignment requires precise measurements and calculations. Shaft alignment fluke 830 laser shaft alignment tool fluke. Measure and correct alignment of the machine to achieve the final alignment to the required targets within tolerances. The procedures for doing this are conceptually simple, but can be tricky to do accurately in the field.
Pdf reports can be generated and directly saved from the system onto a usb stick. Jun 08, 2011 this centers the shaft in the shaft log and gets rid of the wiggle, assuming your cutless bearing was recently replaced. A misalignment of these three components as small as 0. Visually check coupling, pipehangers, base bolts, coupling spacing etc. Shaft alignment and propeller shaft aft bearing performance. The procedure for doing reverse dial indicator alignment is not a difficult one. To achieve this goal, components that are the most likely to fail must. With the motor and pump shaft flanges close to each other, but disconnected, mark a spot on each shaft, then measure the separation between them with a feeler or taper gauge. In fact, the improvements in machine design were critical to the development of thin kerf sawing systems.
With a loadonpad design, figure 1 the shaft is free to laterally within bearing clearance, and alignment data is difficult to obtain without temporary bearing shims to stabilize the sham with a loadbetweenpad design, figure 1 b, the shaft remains stable during the alignment procedure. Shaft alignment report measurement program horizontal operator user measurement unit mils temperature 80. There are several steps which need to be taken for a successful alignment job. The two basic types of misalignment are parallelism and angularity. The shaft alignment training course provides a highly practical knowledge of the use of dial gauge in coupling alignment. Alignment report hung seng huat engineering product co. In the event of a grounding, for instance, small movements at the shaft bearings can impact bearing loads, leading to premature alignment failure. In isolation each strategy can help to reduce unexpected machine failure but taken together they form the hub. Nov 19, 2015 as found shaft alignment results figure 1. The primary and optional data entry windows intuitively tells you what information is required, and if you make a mistake, there are background routines to point out your errors. A practical guide to shaft alignment plant services. In either case, pre alignment is a very important phase of the alignment process. Last but not least, installation, care and maintenance.
If no shaft runout is detected, replace the pulley instead. This laser reference beam passes through the strut tube or cutlass bearing, the stern tube, support bearings, if any, and to the engine or reduction gearbox. To achieve this goal, components that are the most likely to fail must be made to operate within their acceptable design limits. Laser alignment is an essential component of a viable maintenance. Since the pump shaft can not be turned when uncoupled and resting on the bottom, the laser readings were taken using the static measurement mode, which is a process that permits a reading to be taken in any cardinal or subcardinal position.
Design and follow up requirements are published in part 6, chapter 2, section 10 and part 7, chapter 1, section 6 38 respectively of the dnv gl rules for classification of ships. When its centered, the shaft droop will have been eliminated. One owner who recognised the importance of monitoring shaft alignment was stelmar, following the grounding of its aframax tanker keymar. The subject of shaft alignment tolerances has been touched on before but a couple interesting discussions have taken place recently during training classes. Now comes a discussion of why, unlike in an automotive applications, boat engine drive systems do not indefinetly remain in alignment and need to be periodically checked and realigned. Empowering pumps is the information and connection hub for the global pump industry. For instance, if the inner diameter of the shaft log is 1.
Dial gauge alignment procedure in covered with detailed animation. For example, the only correct way to express shaft alignment tolerances is in terms of alignment conditions at the coupling, and we will describe several ways to do this. The main purpose of shaft alignment is to make sure that the center line of the motor rotor shaft coincides with the center line of the driven machinery i. Understanding the need for offset shaft alignment vibralign. You must first take the wobble out of it, then align the coupling flange on. These are but a few of the damages that can be caused by basic engine shaft misalignment. Destructive misalignment forces are generated at the planes of power transmission when the machines are coupled. The 7 steps to proper machinery alignment hp reliability. Shaft alignment training course ppt presentation and. Vessel shaft, strut, engine, and bearing aligment michael h. The ins and outs of engine and shaft alignment part i.
Here the laser has been positioned in the aftmost shaft bearing, and aimed at the transmission output coupling. Does your organization recognize the importance of proper machinery alignment. The data validity rule 1 shown in following equation. Introduction the main propulsion shaft line is the essential part of a modern ship propulsion system, exposed to various conditions throughout the ships lifetime. Engineer, thin kerf technologies inc accurate sawing requires attention to proper alignment and maintenance. Design process the classic alignment technique would. Needless to say, you can only do this with a bearing that is. Asaresultoftheirinherent accuracy, laser alignment systems have been widely applied for a diverse range of sha alignment applications, including. As is shown the best way to know if you have a good hot alignment is to measure it, if at all possible. This alignment technique uses a laser mounted in the region of the propeller and projects a laser reference beam forward. The objective of precision shaft alignment is to remove destructive forces that cause premature bearing failure and reduce seal life. Hydro tasmania shares ideas for improving the alignment process. The fluke 830 laser shaft alignment tool is the ideal test tool to precisionalign rotating shafts in your facility.
Infiltration of corrosive gases, liquids including water or solids can result in corrosive chemical reactions on bearing, gear and seal contact surfaces that can cause premature failure or abnormally high wear rates. An essential component of any successful alignment procedure is the. Achieving proper alignment, however, involves much more than merely adjustment the machines so that the shafts are coaxial. Our alignment software is used for preparing, analyzing, archiving measurement files and printing professional reports. And yet, even excellent alignment of the shaft centers of rotation does not in itself. The fixturlaser xa is capable of doing this type of alignment using a special bracket set and alignment program. Bearing clearance radial gap between the shaft and the bearing shell. After completing this course, participants should be able to describe the basic types of misalignment, describe general preparations for a rim and face shaft alignment procedure, and explain how to use the rim and face shaft alignment procedure.
The bent shaft affects alignment process by showing improper reading. Proper alignment of rotating equipment has a long been recognized as a prerequisite to safe, reliable operation. Shaft alignment is the process whereby two or more machines typically a motor and pump are positioned such that at the point of power transfer. Engines, gearboxes and propeller shafts on ships are aligned using the easylaser system. Alignment tools and procedures that take thermal growth. Number what is shaft alignment 6 a definition 6 machine catenary 7 operation above critical speed 8 expressing alignment 10 alignment parameters 10 angularity, gap and offset 11 short flexible couplings 14 spacer shafts 15 how precise should alignment be. Running gear alignment professional boatbuilder magazine. Not the least of these is the difficulty of turning the shafts. The pre alignment process could include all of the following checks. All of a sudden i have been asked to witness shaft alignment using dial indicators face and rim method. Use this simple and effective procedure for shaft alignment of your rotating equipment. Jul 26, 2014 alignment procedure taking alignment readings step no. Measure, diagnose, and correct soft foot with the assistance of the laser system and feeler gauges.
Precision shaft alignment is possible reliable plant. Improper alignment leads to increase of stresses in the shafts and thus on the equipment, which might result in. While engine alignment is well understood by most marine industry professionals, shaft alignment is far more esoteric and well understood by far fewer folks in the industry. Alignment process alignment process consists of the design and analysis, the alignment procedure and measurements. Every shaft rotates around an axis that forms a straight line. The alignment training is suitable for technicians undertaking machine alignment, coupling alignment, motor alignmnet, pump alignment. Now the shaft alignment measurement procedure can begin. The alignment of shaft with the bearing and housing, which is a manufacturing tolerance stackup of the bearing parts and the housing bores and faces. Shaft alignment of a vertical hydro turbinegenerator unit is a crucial yet highly specialized technical skill. When you opt to use your own shaft alignment tolerances instead of using the industry standards, how do you decide what to use.
Practical alignment tools and techniques bruce lehmann sr. The proper shaft alignment procedure is to secure the driven equipment first because moving a pump, for. Dec 01, 2002 shaft alignment tolerances historically, shaft alignment tolerances have been governed by the coupling manufacturers design specifications. Avace mafactri office the importance of motor shaft alignment the objective of optimized shaft alignment is to increase the operating life span of rotating machinery. The original function of a flexible coupling was to accommodate the small amounts of shaft misalignment remaining after the completion of a shaft alignment using a straight edge or feeler gauges. This also coincides with evolving trends comprising of larger and heavier propellers operating at a lower rpm and different types of stern. It is incorrect to describe them in terms of correction values at the machine feet, and we will examine why.