Shaft alignment, whirling and axial vibration calculations are traditionally regarded as three much separated mathematical problems. Formula for face and rim alignment calculation free download as word doc. The intuitive and affordable laser shaft alignment system skf shaft alignment tool tksa 31 the tksa 31 is skf s most affordable solution for easy laser shaft alignment. The book is reference material on rotating machinery basics, pump overhaul, mechanical seals, basic vibration, and shaft alignment. If a manufacturer of a machine or coupling require tighter alignment tolerances, those should be used. Facilities instructions, standards, and techniques volume. Machinery alignment tolerance tables the suggested alignment tolerances shown here are general values based upon experience and general industry standards and should not be exceeded.
The primary reasons why machinery is misaligned is lack of proper training, improper tools to do the job, and that people are not given enough time to do it right. All measurements are taken on the rim of the coupling hubs. Shaft alignment is the positioning of the rotational centers of two or more shafts such that they are colinear when the machines are under normal operating conditions. Reverse alignmentunderstanding centerline measurement by. The adjustment quantity of the driven shaft s can be calculated according to the data measured by psd. It is not intended as a comprehensive guide to alignment of process machinery, nor is it a substitute for seeking professional advice or reference to the manufacturers of the machinery. The alignment of misaligned shaft are done by using different types of shaft alignment methods which are mention below. A practical guide to shaft alignment plant services. Dbse stands for distance between shaft ends during alignment. By far the most accurate way to calculate motorpump alignment, pulsating laser devices determine shaft positions, relaying the information to a microprocessor that calculates needed alignment changes. With skf s proprietary stateoftheart shaftdesigner software you can quickly and easily calculate shaft and propeller alignment. Regardless of the alignment method you select, you must start with a pump and driver in good repair. Shaft alignment should be an organized and simple process.
Shaft alignment is the process of aligning two or more shafts with each other to within a tolerated margin. Live view supports intuitive measurements and facilitates horizontal and vertical. In fact, the improvements in machine design were critical to the development of thin kerf sawing systems. Misalignment may account for over 50% of malfunctions in rotating machinery, leading to problems such as worn or broken couplers, vibration, and excessive wear of bearings, seals and wear rings. Introduction the main propulsion shaft line is the essential part of a modern ship propulsion system, exposed to various conditions throughout the ships lifetime. Its a simple calculationwe just needed a hot alignment point and a cold or ambient alignment point. Jaryszkami ska, sighting through as part of shaft alignment procedure 68 0,001 0,01 0,1 1 10 a b c piano wire optical instrument laser instrument fig. The indicators are zeroed on the top and read at the bottom. It is the axial spacing between shafts to allow for expansion during operation. The motor is the prime mover, transferring power to the pump by the use of a coupling. This procedure, the four easy steps to good shaft alignmentis. Coupling of main engine with shaft line to be performed according to shaft calculation, sag and gap for the flange coupling between intermediate shaft engine crankshaft. Motorpump alignment is the process of aligning shaft centerlines between a motor and a pump. A new motion graphic from ludeca outlines an easy and effective way to align your rotating equipment and brings you one step closer to best.
The following sections provide information on spiral curve elements, nomenclatureand formulas. These shaft alignment calculations fem model can be used in the early design stage of a vessel or later in the operating stage to ensure correct alignment of your propulsion line. Peterson alignment kits utilize the rimandface method of shaft alignment. The goal of the alignment process is to create a straight line through the coupling. If you would like, start out with an outline of whats involved in doing an alignment. 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 data validity rule 1 shown in following equation. Rotating machinery rotor balancing lifetime reliability. Mathematical formulas are then used to calculate alignment changes. This course begins with the fundamental principles behind shaft to shaft alignment and concludes with students conducting a series of alignment exercises using conventional alignment tools. The rimface method is recognized as the oldest method of shaft alignment. It uses two dial indicators, one on each shaft, to measure the parallel and angular misalignment as shown in figure 21.
A perfectly aligned piece of junk is still a piece of junk. Moreover, as the name suggests, 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. It means no more than an acceptable magnitude of vibration is caused by the unbalance remaining in the rotor. What is the formula of rim and face coupling alignment. Alignment of the shaft is necessary when the motor or driven machinery is new or when it is dismantled due to improper running.
The bent shaft affects alignment process by showing improper reading. The ergonomic display unit with touch screen makes the instrument very easy to use and the builtin machine library helps storing alignment reports for multiple machines. Compressor engineering corporation in the optical alignment field, until the formation in i985 of bently nevada alignment service corporation. Care has been taken by the authors, pruftechnik ltd, in the preparation of this publication. Shaft alignment training course ppt presentation and. If the movable shaft is above the horizontal stationary shaft reference line the shaft is too high. The minimum swing radius when mounted on a 1 shaft is 538. Dial gauge alignment procedure in covered with detailed animation. We were using the fixturlaser go pro, so we took the chance to calculate the shaft alignment targets ourselves. Two dial indicators are used to obtain numbers from the moveable side of a pumpcouplingmotor assembly.
Scribd is the worlds largest social reading and publishing site. The fixtures should include an assortment of rods to span various coupling lengths. With additional chain it can be mounted on shafts over 10. 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. So that i fixed my fixture on movable machine then how i can calculate my bvalue. Alignment and couplings 3 the reverse indicator method is another shaft alignment method. Machinery alignment tolerance tables impact engineering.
Graphical presentation of the distribution of measurement errors for the selected measuring instruments. A static condition observed at the bearings supporting the propulsion shafts. Alignment is critical to modem sawmills using thin kerf saws. Shaft alignment methods explained bright hub engineering.
Alignment of pumps one of the most important parts of pump setup is making sure that the pump and the drive motor are carefully aligned. The vertical move is the part of the alignment process that aligns the two shaft s centerlines into their proper up and down position. By using two dial indicators, one mounted perpendicular to the shaft radial. Appendix h contains additional horizontal and vertical alignment equations that correspond to chapters 3 and 4, as well as the horizontal and vertical alignment example calculations shown in appendix k. It is not intended as a comprehensive guide to alignment of process machinery, nor is it a substitute for seeking professional advice or. A motor with a starting temperature of 70 f is perfectly aligned to the pump shaft it will be driving. The alignment training is suitable for technicians undertaking machine alignment, coupling alignment, motor alignmnet, pump alignment, etc. Accurate shaft alignment is vital to the operating life of rotating equipment. Engineer, thin kerf technologies inc accurate sawing requires attention to proper alignment and maintenance. Shaft alignment procedure mantenimiento planificado. Abstract shaft alignment is a key factor in reducing vibrations and. Bearings, mechanical seals, packing and couplings are all directly affected by the alignment of shaft center lines. 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.
It is important to establish a set procedure to perform alignments. A variety of shaft alignment fixtures are available for performing rimface alignment. This is probably the most common configuration of coupled machines in industry. A good static alignment is required for troublefree dynamic operation of the propulsion shafting. This 2day course begins with the fundamental principles behind shaft to shaft alignment and concludes with students conducting a series of alignment exercises using conventional alignment tools. Rim and face alignment formula method tamil youtube. He is a member of asme, the vibration institute, and the pacific energy association. The purpose of this document is to provide guidance for vertical shaft alignment including when alignment procedures should be considered, and therefore, all information in this document is presented as plain text as required. Several equipment alignment methods, especially the reverse dial indicator method, which is the principle used in laser alignment is covered in explicit detail.
Selection and use of a commercial package designed to accommodate a variety of shaft diameters is recommended. Rotating machinery rotor balancing the aim of rotor balancing is to achieve satisfactory running when installed on site. Usually you will have to add or remove shims in this step. The two most common dial indicator alignment methods are the rimface and reverse rim. Bro in case i cant able to rotate my fixed machine. 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. Proper shaft alignment is not dictated by the total indicator reading tir of the coupling hubs or the shafts, but rather by the proper centers of rotation of the shaft. Practical alignment tools and techniques bruce lehmann sr. Shaft misalignment is responsible for as much as 50 percent of all costs related to rotating machinery breakdowns.
Improper alignment results in excessive vibration, short life of driven equipment compound bearing and coupling clutch parts, and frequent re alignment. In the case of a flexible rotor, it also means that not more than an acceptable magnitude of deflection occurs in the. It is calculated, conducted and verified when the system is at rest. If the movable shaft is below the horizontal stationary shaft reference line, the shaft is too low. The shaft alignment training course provides a highly practical knowledge of the use of dial gauge in coupling alignment. Most make heavy use of algebraic calculations and graphs and are easily subject to error. When interpreting the graph to determine the movable shaft s front and rear feet positions in the ertical plane, observe the following rules. The mechanical device is designed and installed as shown in figure 1.