1 Intro to Mech Drive Systems Job Sheets_Student.pdf

Mechanical Training System Introduction to Mechanical Drive Systems 1-800-Lab-Volt www.labvolt.com 36737-20 |3036737200000b~ Job Sheets - Student  Mechanical Training System Introduction to Mechanical Drive Systems...

Mechanical Training System Introduction to Mechanical Drive Systems 1-800-Lab-Volt www.labvolt.com 36737-20 |3036737200000b~ Job Sheets - Student  Mechanical Training System Introduction to Mechanical Drive Systems Job Sheets – Student 36737-20 A  MECHANICAL TRAINING SYSTEM INTRODUCTION TO MECHANICAL DRIVE SYSTEMS by the Staff of Lab-Volt Ltd. Copyright © 2005 Lab-Volt Ltd. All rights reserved. No part of this publication may be reproduced, in any form or by any means, without the prior written permission of Lab-Volt Ltd. Legal Deposit – Third Trimester 2005 ISBN 978-2-89289-765-4 FIRST EDITION, JULY 2005 Printed in Canada May 2009  Foreword The Lab-Volt Mechanical Training System, Model 46101, is a modular program that covers the installation, use, maintenance, and troubleshooting of mechanical drive systems. The curriculum is divided into five levels, and covers the following topics: C Introduction to mechanical drive systems C Belt drives 1 and 2 C Chain drives 1 and 2 C Gear drives 1 and 2 C Lubrication C Couplings C Shaft alignment C Bearings C Ball screws C Linear bearings C Gaskets and seals C Clutches C Brakes C Laser alignment C Vibration metering This manual Introduction to Mechanical Drive Systems, is the first manual of a series of four supplied with the Mechanical Training System, level 1. The objective of this manual is to introduce the Lab-Volt Mechanical Training System, and to explain important aspects of mechanical drive systems. The other manuals supplied with the Mechanical Training System, level 1, are Belt Drives 1, Chain Drives 1, and Gear Drives 1. III IV  Table of Contents Introduction................................................... VII Job Sheet 1 Introduction to the Mechanical Training System........ 1-1 Job Sheet 2 Safety Procedure................................. 2-1 Job Sheet 3 Key and Setscrew Fasteners........................ 3-1 Job Sheet 4 Speed and Torque Measurements................... 4-1 Job Sheet 5 Efficiency........................................ 5-1 Job Sheet 6 Shafts and Pillow Block Bearings.................... 6-1 Job Sheet 7 Shaft Alignment and Flexible Couplings.............. 7-1 Job Sheet 8 Shaft Alignment and Rigid Couplings................ 8-1 Job Sheet 9 Motor Soft Foot Detection and Correction............. 9-1 Appendices A Unit Conversion Table B Post-Test We Value Your Opinion! V VI  Introduction The topics covered in this manual are presented in the form of Job Sheets. The Job Sheets include a description of the objectives, a list of equipment required, a safety procedure, and a list of steps required to attain the objectives. The topics are usually introduced in an Information Sheet. However, to obtain detailed information about the covered topic, you should refer to your text book or ask your instructor to guide your learning process. Safety Considerations Make sure you are wearing appropriate protective equipment when performing the jobs. You should never perform a job if you have any reasons to think that a manipulation could be dangerous for you or your teammates. Reference Text Book Refer to the manual titled Industrial Maintenance written by Michael E. Brumbach and Jeffrey A. Clade as reference text book. System of Units Most of the components in the Mechanical Training System are machined using the imperial system of units. For this reason the imperial system of units was preferred in the manual. In the figures, however, the distances are also indicated in the SI system. These values are shown in parentheses. Refer to the Unit Conversion Table in Appendix A if necessary. Appendix The appendices included in this manual is: Appendix A: Unit Conversion Table, shows the conversion factors to apply to convert Imperial units to SI units and vice versa. Appendix B: Post-Test, evaluates the knowledge of the topics covered in the Job Sheets. VII VIII  1 INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM DESCRIPTION The Lab-Volt Mechanical Training System, model 46101-10, consists of the Universal Base Assembly, Motor Package, Test and Measurement Package, Tool Box Component Package, the Couplings – Shafts panel, and the Pillow Block Bearings panel. It also includes the following subsystems: Belt Drives 1, Chain Drives 1, and Gear Drives 1. The content of these systems is shown in the corresponding manuals. UNIVERSAL BASE ASSEMBLY The Universal Base Assembly, model 46603, consists of the universal base, prony brake, lockout/tagout device, and padlocks. The components are shown in Figure 1-1. Note: The components will be described more in detail later in this manual. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 1-1 INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM Figure 1-1. Components of the Universal Base Assembly. The universal base is the frame on which mechanical components are mounted. It is supplied with T-slotted extrusions and safety panels. The components are shown in Figure 1-2. 1-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM Figure 1-2. Components supplied with the Universal Base. The universal base includes a disconnecting switch, a control panel, and a Start/Stop station as shown in Figure 1-3. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 1-3 INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM Figure 1-3. Electrical components on the Universal Base. The function of the electrical components is as follows: Disconnecting Switch The disconnecting switch controls the power to the rest of the system. When the disconnecting switch is set to the OFF position, the control panel is not powered. It includes a main breaker. Control Panel Power: lights up when the system is powered (disconnecting switch to ON). Meter: indicates the current value delivered at the Motor outlet. Output Voltage selector: selects between a fixed and variable voltage for the Motor outlet. In the Fixed position, the voltage is fixed. In the Variable position, the voltage is controlled by the potentiometer. Potentiometer: controls the voltage of the Motor outlet when the Output Voltage selector is set to Variable. 1-4 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM Reset button: resets the thermal circuit breaker. The circuit breaker trips when the current exceeds the value indicated on the control panel. Clutch/Brake selector: controls the operation of the clutch/brake assembly. Motor outlet: supplies power to the variable and fixed speed motors. These outlets are not powered when the disconnecting switch is set to the OFF position. Clutch/Brake outlet: supplies the control signals for the clutch/brake assembly. Start/Stop station The Start/Stop station remotely controls the operation of the Motor outlet. Start button (green): allows the Motor outlet to be energized. Stop button (red): de-energizes the Motor outlet. Emergency button (red and bigger than the Stop button): de-energizes the Motor outlet. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 1-5 INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM MOTOR PACKAGE The Motor Package, model 46609, consists of a constant speed motor and a variable speed motor. Both motors come with a mounting base. The components are shown in Figure 1-4. Figure 1-4. Components of the Motor Package. 1-6 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM TEST AND MEASUREMENT PACKAGE The Test and Measurement package, model 46630, includes various tools used to make measurements. The components are shown in Figure 1-5. Figure 1-5. Components of the Test and Measurement Package. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 1-7 INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM TOOL BOX COMPONENT PACKAGE The Tool Box Component package, model 46631, includes various items used to mount components. The components are shown in Figure 1-6. Figure 1-6. Tool Box Component Package. 1-8 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM COUPLINGS – SHAFTS PANEL The Couplings – Shafts panel, model 46610, contains the couplings and shafts required to perform the jobs. The components are shown in Figure 1-7. Figure 1-7. Couplings – Shafts panel. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 1-9 INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM PILLOW BLOCK BEARINGS PANEL The Pillow Block Bearings panel, model 46611, contains the pillow bock bearings required to perform the jobs. The components are shown in Figure 1-8. Figure 1-8. Pillow Block Bearings panel. 1-10 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  1 INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM OBJECTIVES In this job, you will install T-slotted extrusions on the universal base. You will also install the motors. EQUIPMENT REQUIRED C Universal Base Assembly, model 46603 C Motor Package, model 46609 C Tool Box Component Package, model 46631 SAFETY PROCEDURE Before proceeding with this job, complete the following check list. G You are wearing safety glasses. G You are wearing safety shoes. G You are not wearing anything that might get caught such as a tie, jewelry, or loose clothes. G If your hair is long, tie it out of the way. G The working area is clean and free of oil. G The floor is not wet. G Your sleeves are rolled up. PROCEDURE Installation of T-Slotted Extrusions Note: Make sure that the Mechanical Training System is not connected to an outlet when performing this job. G 1. Fix a corner bracket to a T-slotted extrusion bar with a 5/16-18 x 5/8-in. BHSCS screw (Button Head Socket Cap Screw) along with a T-nut using a 3/16-in. hexagonal key. Make sure that the side of the corner bracket is flush with the extrusion bar end as shown in Figure 1-9. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 1-11 INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM Figure 1-9. Installation of the corner brackets. G 2. Fix a second corner bracket to the extrusion bar. Hand-tighten the screw to make sure the corner bracket can slide freely in the slot of the extrusion bar. G 3. Position and fix the extrusion bar to the universal base with 5/16-18 x 5/8-in. BHSCS screws along with T-nuts as shown in Figure 1-10. G 4. Install a second extrusion bar to complete the setup shown in Figure 1-10. G 5. Make sure all screws are tightened. Constant Speed Motor Installation G 6. Install the constant speed motor mounting base on the extrusions using the 5/16-18 x 5/8-in. HHCS (Hexagonal Head Cap Screw) screws, flat washers, and T-nuts as shown in Figure 1-11. Do not yet tighten the screws so the base can slide freely on the extrusions. 1-12 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM Figure 1-10. Universal base setup. Figure 1-11. Constant speed motor mounting base installation. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 1-13 INTRODUCTION TO THE MECHANICAL TRAINING SYSTEM G 7. Position the motor mounting base as shown in Figure 1-10. G 8. Pull the motor mounting base firmly against the extrusion bars and tighten the screws with a 1/2-in. wrench using a criss-cross pattern. G 9. Position and fix the constant speed motor to the mounting base with the 5/16-18 x 5/8-in. HHCS screws and flat washers, as shown in Figure 1-10. Variable Speed Motor Installation G 10. Install the variable speed motor and base assembly on the extrusions using the 5/16-8 x 5/8-in. HHCS screws, flat washers, and T-nuts. Do not yet tighten the assembly so the base can slide freely on the extrusions. G 11. Position the motor mounting base as shown in Figure 1-10. G 12. Pull the motor mounting base firmly against the extrusion bars and tighten the screws to the extrusions using a wrench. G 13. Ask the instructor to check your work. G 14. Disassemble the setup and return the components to the storage location. Name: Date: Instructor's approval: 1-14 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  2 SAFETY PROCEDURE Mechanical drive systems involve devices in motion. Serious injuries to you or your teammates can occur if the following safety recommendations are not followed correctly. Lockout/Tagout The lockout procedure consists in the installation of a locking mechanism on the power switch or any other energy source to which the equipment is connected. The objective of the lockout is to prevent an unexpected startup of machinery during installation and maintenance operations. The Mechanical Training System is supplied with Lockout/Tagout devices as shown in Figure 2-1. Each person involved in the job must install a padlock. Figure 2-1. Lockout/Tagout devices. The tagout procedure consists in the installation of a tag to warn that a mechanism as been locked. It indicates that no one should attempt to operate the equipment. The tag also indicates the name of the person(s) who can remove the lockout device. Safety Panels The Mechanical Training System is supplied with safety panels as shown in Figure 2-2. A setup should never be powered without the panels. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 2-1 SAFETY PROCEDURE Figure 2-2. Safety panels. Clothing and Personal Protective Equipment Wearing appropriate clothes and protective equipment is essential to limit the risk of injury, but it is important to have in mind that protective equipment is not a substitute for good work practices. C Always make sure that the clothes you are wearing might not get caught in rotating equipment. Ties, jewelry, watches, or loose clothes must be avoided. If you wear a jacket with sleeves, always roll them up. C Always wear safety glasses and protective shoes. Remember that many injuries result from wearing improper or poorly fitting protective equipment. C When wearing gloves to perform a task, always make sure that they cannot get caught in rotating equipment. C If your hair is long, tie it out of the way. Working Environment Installation and maintenance operations require a safe working environment. C Keep the working environment free of debris and other obstructions such as tools or loose parts. C Floors should be clean and free of oil to insure good footing and balance. C Always keep drives properly guarded when in operation. 2-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  2 SAFETY PROCEDURE OBJECTIVES In this job, you will perform a Lockout/Tagout Procedure. You will also install the safety panels on the universal base. EQUIPMENT REQUIRED C Universal Base Assembly, model 46603 SAFETY PROCEDURE Before proceeding with this job, complete the following check list. G You are wearing safety glasses. G You are wearing safety shoes. G You are not wearing anything that might get caught such as a tie, jewelry, or loose clothes. G If your hair is long, tie it out of the way. G The working area is clean and free of oil. G The floor is not wet. G Your sleeves are rolled up. PROCEDURE Lockout/Tagout Procedure G 1. Make sure the power light on the control panel is turned off. If not, set the disconnecting switch to the OFF position by pressing the lever downward. G 2. Write your name on a tag, and install it in the lockout device. G 3. Install the lockout device in the disconnecting switch. G 4. Lock the lockout device with your padlock, as shown in Figure 2-3. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 2-3 SAFETY PROCEDURE Figure 2-3. Lockout/tagout setup. G 5. Ask each teammate to install their own padlocks in the lockout device. Safety Panel Installation G 6. Install a large safety panel in the slot at the rear of the universal base. Make sure the panel is centered on the metal pin at the bottom of the slot. G 7. Install a small safety panel in the slot on each side of the universal base. G 8. Align the push-lock fasteners on the rear panel with the perforated corner brackets on the side panels as shown in Figure 2-4. G 9. Firmly push the fasteners into the holes until a click is heard. G 10. Install a large safety panel in the slot at the front of the universal base and lock it with the side panels as shown in Figure 2-5. 2-4 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  SAFETY PROCEDURE Figure 2-4. Joining the safety panels. Figure 2-5. Safety panel setup. G 11. Ask the instructor to check your work. G 12. Return the components to the storage location. Name: Date: Instructor's approval: INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 2-5 2-6 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  3 KEY AND SETSCREW FASTENERS Key Fasteners Key fasteners are used to transmit torque and prevent relative rotation between components such as sheaves, sprockets or gears, and shafts. A key fastener is composed of three parts: the key, the keyseat located on the shaft, and the keyseat machined into the hub of the component as shown in Figure 3-1. Figure 3-1. Key fastener components. Keys and keyseats are cut and machined in standard sizes. Their height, width, and depth depend mainly on the shaft diameter and on the key type used. Setscrews A setscrew is a threaded fastener, with or without a head, used to limit the relative rotation and axial displacement between a sheave, sprocket or gear, and a shaft. Setscrews are machined with different tips. The tip design depends on the desired contact force and allowable shaft deformation. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 3-1 KEY AND SETSCREW FASTENERS Setscrews should be tightened on a key or on the flat surface of the shaft (if a flat surface is present). Otherwise, the shaft surface may be marked by the setscrew. Setscrews are inserted in threaded holes inside the hub of the components as shown in Figure 3-2. Figure 3-2. Setscrew location. 3-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  3 KEY AND SETSCREW FASTENERS OBJECTIVES In this job, you will measure a shaft keyseat and cut a key from the key stock. You will also install a hub on a motor shaft. EQUIPMENT REQUIRED C Universal Base Assembly, model 46603 C Motor Package, model 46609 C Tool Box Component Package, model 46631 SAFETY PROCEDURE Before proceeding with this job, complete the following check list. G You are wearing safety glasses. G You are wearing safety shoes. G You are not wearing anything that might get caught such as a tie, jewelry, or loose clothes. G If your hair is long, tie it out of the way. G The working area is clean and free of oil. G The floor is not wet. G Your sleeves are rolled up. PROCEDURE Lockout/Tagout Procedure G 1. Set the disconnecting switch to OFF. G 2. Write your name on a tag, and install it in the lockout device. G 3. Lock the disconnecting switch with the lockout device. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 3-3 KEY AND SETSCREW FASTENERS G 4. Lock the lockout device with your padlock. G 5. Ask the instructor and each teammate to install their own padlocks in the lockout device. Keyseat Measurement G 6. Install two extrusions on the universal base as shown in Figure 3-3. Figure 3-3. Universal base setup. G 7. Fix the constant speed motor on the extrusions as shown in Figure 3-3. G 8. Using the small jaws of a dial caliper, measure the width of the constant speed motor shaft keyseat as shown in Figure 3-4. Shaft keyseat width: 3-4 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS KEY AND SETSCREW FASTENERS Figure 3-4. Width measurement of the shaft keyseat. G 9. Using the dial caliper, measure the height of the motor shaft keyseat as shown in Figure 3-5. Shaft keyseat height: Figure 3-5. Height measurement of the shaft keyseat. G 10. Using a rule, measure the length of the motor shaft keyseat. Shaft keyseat length: Note: Measure only the usable keyseat length, which does not include the round section. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 3-5 KEY AND SETSCREW FASTENERS Cutting a Shaft Key G 11. Get the key stock from the tool box and measure the width and height using a dial caliper. Key stock width: Key stock height: G 12. Using a bench vise and a hacksaw, measure and cut the key stock to obtain a key with a length of 1.38 in., as shown in Figure 3-6. Note: Make sure you do not mark the key stock by over tightening the jaws. Figure 3-6. Cutting a shaft key. G 13. Using a file, burr the cut and slightly chamfer the edges of the shaft key. Hub Installation G 14. Install the key you cut into the motor shaft keyseat. Make sure the key is in line with the end of the shaft. G 15. Align the hub keyseat of the prony brake with the key on the motor shaft, and slide the hub on the shaft. 3-6 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS KEY AND SETSCREW FASTENERS G 16. Tighten the hub setscrew on the key. Note: Make sure the setscrew is not tightened directly on the motor shaft keyseat. G 17. Ask the instructor to check your work. G 18. Do not disassemble the setup now if you expect to be the next team to use the universal base. If not, disassemble the setup and return the components to the storage location. Name: Date: Instructor's approval: INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 3-7 3-8 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  4 SPEED AND TORQUE MEASUREMENTS Tachometer The angular velocity of a shaft, also called speed, is measured using a tachometer. The speed can be measured by applying a probe directly on a rotating shaft, but it is often difficult or dangerous to do so. Another method is to use a photo-reflective tachometer, which uses a light beam to detect the speed. The light beam is emitted by the tachometer and reflected back by the rotating component to the tachometer. The measured speed is indicated on a display as shown in Figure 4-1. The units displayed are expressed in r/min, also noted RPM. Figure 4-1. Speed measurement using a photo-reflective tachometer. Prony Brake A prony brake provides a means for applying an adjustable load torque to the output shaft of a prime mover such as a motor. It consists of two spring scales, a balance, a load adjustment wing nut, a counterweight, a break drum (hub), and a friction belt, as shown in Figure 4-2. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 4-1 SPEED AND TORQUE MEASUREMENTS Figure 4-2. Prony brake. The power output is dissipated as heat in the braking material as the shaft rotates. The load on the motor shaft is adjusted by tightening or loosening the wingnut located on the top of the prony brake frame, causing the torque to increase or decrease on the hub. The load applied is read directly on the spring scales. With the lever-arm length being known, the torque can be calculated as follows: where T is the torque in lbfAin.; F is the load in lbf.; L is the lever-arm length in inches. 4-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  4 SPEED AND TORQUE MEASUREMENTS OBJECTIVES In this job, you will join a prony brake to a motor. You will use a photo-reflective tachometer to measure the speed of a shaft. You will also use a prony brake to apply a torque on the motor shaft. EQUIPMENT REQUIRED C Universal Base Assembly, model 46603 C Motor Package, model 46609 C Tool Box Component Package, model 46631 SAFETY PROCEDURE Before proceeding with this job, complete the following check list. G You are wearing safety glasses. G You are wearing safety shoes. G You are not wearing anything that might get caught such as a tie, jewelry, or loose clothes. G If your hair is long, tie it out of the way. G The working area is clean and free of oil. G The floor is not wet. G Your sleeves are rolled up. PROCEDURE Lockout/Tagout Procedure G 1. Set the disconnecting switch to OFF. G 2. Write your name on a tag, and install it in the lockout device. G 3. Lock the disconnecting switch with the lockout device. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 4-3 SPEED AND TORQUE MEASUREMENTS G 4. Lock the lockout device with your padlock. G 5. Ask the instructor and each teammate to install their own padlocks in the lockout device. Note: The universal base should be set up from Job Sheet 3. Repeat Job Sheet 3 if necessary. Prony Brake Installation G 6. Complete the setup of Job Sheet 3 by installing two T-slotted extrusions as shown in Figure 4-3. Figure 4-3. Universal Base setup. Note: Make sure the spring scales are installed on the left side. G 7. Position the prony brake on the extrusions, and center the hub on the friction belt. 4-4 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  SPEED AND TORQUE MEASUREMENTS G 8. Fix the prony brake on the extrusions with the 5/16-18 x 5/8-in. HHCS screws, flat washers, and T-nuts. G 9. Fill the hub with water as shown in Figure 4-4. Note: Water is used to dissipate heat generated by friction between the rotating hub and friction belt. Figure 4-4. Filling the hub of the prony brake with water. G 10. Make sure that a reflective tape is present on the hub. If not, ask your instructor to install a tape. G 11. Make sure that the two spring scales indicate zero. If not, adjust the scales to zero by sliding the metal tab up or down. Start-up Procedure G 12. Connect the motor to the Motor outlet on the frame of the universal base. G 13. Ensure that all screws and setscrews are tightened. G 14. Install the safety panels. G 15. Ask your instructor to inspect the setup. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 4-5 SPEED AND TORQUE MEASUREMENTS G 16. Ask each person to remove its padlock from the lockout device. G 17. Remove the lockout/tagout device. G 18. Ensure that the Voltage Output selector is set to FlXED. G 19. Set the disconnecting switch to ON. G 20. Start the motor by pressing the Start button on the Start/Stop station. Speed G 21. For each load value shown in Table 4-1, measure the speed of the motor using the photo-reflective tachometer as shown in Figure 4-5. Make sure that the load on each spring scale is half the load value shown in the table. Enter your results in the Speed column. Note: Since you must enter an arm in the universal base to vary the load while the motor is running, be careful. Do not let the hub run without water. If water is required, stop the motor by pressing the Stop button on the Start/Stop station, set the disconnecting switch to OFF, remove the front security panel, and add water. Figure 4-5. Speed measurement using the photo-reflective tachometer (shown without safety panels). 4-6 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  SPEED AND TORQUE MEASUREMENTS LOAD SPEED TORQUE TORQUE oz r/min ozfAin. lbfAft 0 8 16 24 32 Table 4-1. Speed and torque measurements. G 22. Stop the motor by pressing the Stop button on the Start/Stop station. G 23. Set the disconnecting switch to OFF. G 24. Perform the Lockout/Tagout Procedure. Torque G 25. Calculate the torque delivered by the motor for each load value. The lever- arm length of the prony brake is 6 in. and the equation is T = FL. Enter your results in the Torque (ozfAin) column. G 26. Convert each torque value from ozfAin to lbfAft, which is commonly used to express torque. Enter your results in the Torque (lbfAft) column. Note: Multiply the values in ozfAin by 0.0052 to get the corresponding values in lbfAin. G 27. Ask the instructor to check your work. G 28. Do not disassemble the setup now if you expect to be the next team to use the universal base. If not, disassemble the setup and return the components to the storage location. Name: Date: Instructor's approval: INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 4-7 4-8 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  5 EFFICIENCY Efficiency is usually defined as the ratio of the power delivered by a system to the power supplied. Because of losses, this efficiency is always less than 100%. Rotating machine losses come from mechanical and electrical losses. The efficiency of a system is expressed as follows: where η is the efficiency of the system; Pout is the delivered power in watts; Pin is the supplied power in watts. POWER The electrical power supplied to a motor (Pin) is determined using an instrument named wattmeter. When the torque and the speed are known, the delivered power (Pout) can be calculated as follows: where Pout is the power in watts; T is the torque in lbfAft; n is the speed of the shaft in r/min. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 5-1 5-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  5 EFFICIENCY OBJECTIVES In this job, you will determine the efficiency of a system by comparing the input and output powers. There is no setup to prepare for this Job Sheet. EQUIPMENT REQUIRED C Calculator C Torque values determined in Job Sheet 4 PROCEDURE Output Power G 1. Use the speed (r/min) and torque (lbfAft) values shown in Table 4-1, and the formula Pout = 0.142Tn to determine the output power (Pout) in watts. Enter your results in the Pout column of Table 5-1. Pin LOAD W Pout EFFICIENCY oz W % 120 V 60 Hz1 220 V 50 Hz2 0 159 210 8 218 253 16 286 302 24 368 359 32 456 429 (1) - Use these values if your electrical network voltage and frequency are 120 V 60 Hz. (2) - Use these values if your electrical network voltage and frequency are 220 V 50 Hz. Table 5-1. Parameters used to determine the efficiency. Efficiency Note: Since you do not have the facilities to measure the electrical input power Pin, you will use values already measured for your calculations. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 5-3 EFFICIENCY G 2. Determine the efficiency (%) of the system using the input and output power values shown in Table 5-1 and the formula η = Pout/Pin × 100. Enter your results in the Efficiency column of Table 5-1. Note: Observe that the system efficiency is much less than 100%, and that it increases with the load. G 3. Ask the instructor to check your work. Name: Date: Instructor's approval: 5-4 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  6 SHAFTS AND PILLOW BLOCK BEARINGS Shafts Shafts are rotating elements, on which components such as sheaves, sprockets, or gears are mounted, that are used to transmit energy from a prime mover to a load. The shaft cross-sections may be round, square, or hexagonal. Round keyed shafts are widely used because of economic and maintenance considerations. They can be machined with a keyseat to receive a key and/or a flat surface on which a setscrew can be snugged, as shown in Figure 6-1. Figure 6-1. Shaft with a keyseat and a flat surface. Pillow Block Bearings Bearings are used to reduce friction between parts in motion and to support shafts. A pillow block bearing consists of a housing, a bearing, and a grease fitting for lubrication as shown in Figure 6-2. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 6-1 SHAFTS AND PILLOW BLOCK BEARINGS Figure 6-2. Pillow Block Bearings. Pillow block bearings are used in many type of machines and equipment that have no housing for the bearing. Most pillow block bearings incorporate self-aligning bearings that do not require precision mountings. 6-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  6 SHAFTS AND PILLOW BLOCK BEARINGS OBJECTIVES In this job, you will measure a shaft and identify its main feature. You will also install a shaft supported by two pillow block bearings. EQUIPMENT REQUIRED C Universal Base Assembly, model 46603 C Couplings – Shafts Panel, model 46610 C Pillow Block Bearings Panel, model 46611 C Tool Box Component Package, model 46631 SAFETY PROCEDURE Before proceeding with this job, complete the following check list. G You are wearing safety glasses. G You are wearing safety shoes. G You are not wearing anything that might get caught such as a tie, jewelry, or loose clothes. G If your hair is long, tie it out of the way. G The working area is clean and free of oil. G The floor is not wet. G Your sleeves are rolled up. PROCEDURE Shaft Dimensions G 1. Using a tape rule, measure the length of the shafts from the Couplings – Shafts Panel. Short shaft length: Long shaft length: INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 6-3 SHAFTS AND PILLOW BLOCK BEARINGS G 2. Using a dial caliper, measure the diameter of a 9-in. shaft. Shaft diameter: Pillow Block Bearing Installation G 3. Fix two T-slotted extrusions on the universal base as shown in Figure 6-3. Figure 6-3. Universal base setup. G 4. Fix two pillow block bearings and risers on the extrusions using the 5/16-18 x 3 1/4-in. HHCS screws, washers, and T-nuts as shown in Figure 6-4. Note: Risers are used to fit the height of two shafts. Make sure the setscrews of the pillow block bearings are oriented as shown in Figure 6-3. 6-4 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  SHAFTS AND PILLOW BLOCK BEARINGS Figure 6-4. Pillow block bearing installation. G 5. Slide a 14-in. shaft through the pillow block bearings. Do not tighten the pillow block bearing setscrew on the shaft now. Note: Final installation will be completed in the next job sheets. G 6. Tighten the screws. G 7. Ask the instructor to check your work. G 8. Do not disassemble the setup now if you expect to be the next team to use the universal base. If not, disassemble the setup and return the components to the storage location. Name: Date: Instructor's approval: INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 6-5 6-6 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  7 SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS Flexible shaft couplings are used for joining shafts of equal or different diameters. A flexible jaw coupling is shown in Figure 7-1. Figure 7-1. Flexible coupling. Flexible couplings can usually compensate for slight errors in shaft alignment. Manufacturers usually specify the maximum allowable misalignment values. Improper shaft alignment can lead to premature failure of couplings and bearings, and may cause excessive vibration. ALIGNMENT The two basic types of shaft misalignment are parallel and angular. Parallel Misalignment Parallel misalignment results when two shafts are parallel but not on the same plane, as shown in Figure 7-2. Figure 7-2. Parallel misalignment. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 7-1 SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS A straightedge and a feeler gauge are placed around the periphery of the coupling halves to check the parallel alignment on the vertical and horizontal planes. Alignment is adjusted in the vertical plane by raising or lowering one of the component with shims. Alignment is adjusted in the horizontal plane by moving a component to the right or left. Angular Misalignment Angular misalignment, also called axial misalignment, results when the shafts are at a different angle with the horizontal or vertical planes as shown in Figure 7-3. Figure 7-3. Angular misalignment. Both the vertical and horizontal planes must be checked to ensure a correct angular alignment. A dial caliper is used to check the angular alignment. Alignment is adjusted in the vertical plane by titling a component on its base with shims. Alignment is adjusted in the horizontal plane by rotating a component in the appropriate direction. 7-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  7 SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS OBJECTIVES In this job, you will perform a shaft alignment and install a flexible jaw coupling. EQUIPMENT REQUIRED C Universal Base Assembly, model 46603 C Motor Package, model 46609 C Couplings – Shafts Panel, model 46610 C Pillow Block Bearings Panel, model 46611 C Test/Measurement Package, model 46630 C Tool Box Component Package, model 46631 SAFETY PROCEDURE Before proceeding with this job, complete the following check list. G You are wearing safety glasses. G You are wearing safety shoes. G You are not wearing anything that might get caught such as a tie, jewelry, or loose clothes. G If your hair is long, tie it out of the way. G The working area is clean and free of oil. G The floor is not wet. G Your sleeves are rolled up. PROCEDURE Lockout/Tagout Procedure G 1. Set the disconnecting switch to OFF. G 2. Write your name on a tag, and install it in the lockout device. G 3. Lock the disconnecting switch with the lockout device. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 7-3 SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS G 4. Lock the lockout device with your padlock. G 5. Ask the instructor and each teammate to install their own padlocks in the lockout device. Note: The universal base should be set up from Job Sheet 6. Repeat Job Sheet 6 if necessary. Universal Base Setup G 6. Fix two T-slotted extrusions on the universal base to complete the setup shown in Figure 7-4. Figure 7-4. Universal base setup. G 7. Fix the constant speed motor to the extrusions. G 8. Install a shaft key in the motor shaft keyseat. 7-4 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS Coupling Installation G 9. Align the keyseat of a 0.625-in. jaw coupling half with the key on the motor shaft, then slide the coupling on the shaft. Make sure the jaw coupling half is flush with the key end. G 10. Tighten the coupling setscrew on the key. G 11. Install a key in the keyseat of the shaft supported by the pillow block bearings. G 12. Align the keyseat of the other 0.625-in. jaw coupling half with the key on the shaft, slide the coupling on the shaft until it is flush with the shaft end, and tighten the coupling setscrew. G 13. Install the insert for jaw coupling in the jaw coupling half on the motor shaft. G 14. Slide the shaft supported by the pillow block bearings to obtain a 0.5-in. gap between the two coupling halves as shown in Figure 7-5. Tighten the pillow block bearing setscrews on the flat surface of the shaft. Figure 7-5. Coupling gap. Vertical Angular Alignment G 15. Mark both coupling halves with a soapstone marker, then align the marks. Note: The soapstone marks will be used for all alignment procedures. They ensure that the coupling halves are in the same relative positions for all measurements. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 7-5 SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS G 16. Position the coupling halves so that the soapstone marks are at the 12-o'clock position. G 17. Measure the A1 distance at the 12-o'clock position with a dial caliper as shown in Figure 7-6. A1 distance at the 12-o'clock position: Figure 7-6. Vertical angular alignment. G 18. Position the coupling halves so that the soapstone marks are aligned at the 6-o'clock position. G 19. Measure the A2 distance at the 6-o'clock position. A2 distance at the 6-o'clock position: G 20. Calculate the vertical angular misalignment by subtracting the smaller distance from the larger. Note the position at which the larger distance was measured. Vertical angular misalignment: Position of the larger distance: G 21. Measure the outside diameter of the coupling halves. Coupling outside diameter: 7-6 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS G 22. Measure the distance between the slots on the motor base plate as shown in Figure 7-7. Distance between the slots on the motor base plate: Figure 7-7. Distance between the slots of the motor base plate. G 23. Calculate the shim ratio using the following formula: where Sr is the shim ratio; L is the distance between the slots of the motor base, in inches; D is the coupling diameter, in inches. Shim ratio: G 24. Calculate the shim thickness using the following formula: where St is the shim thickness in inches; Sr is the shim ratio; Vam is the vertical angular misalignment in inches. Shim thickness: G 25. Determine which side of the motor must be shimmed. Shim the shaft side of the motor if the larger distance was measured at the 6-o'clock position. Otherwise, shim the back side. Side to shim: G 26. On the motor side to shim, loosen the screws, install the shims, and tighten the screws. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 7-7 SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS Note: An equal thickness of shims must be installed under the motor screws to raise the motor evenly. G 27. Recalculate the vertical angular misalignment, and repeat the procedure until it is less than 0.030 in. Vertical Parallel Alignment G 28. Position the coupling halves so that the soapstone marks are aligned at the 12-o'clock position. G 29. Lay a straightedge on the soapstone marks, then measure the gap using a feeler gauge as shown in Figure 7-8. Gap: Note: The measured gap corresponds to the required shim thickness. Figure 7-8. Vertical parallel alignment. G 30. Loosen the screws on the motor shaft side, install the shims, and tighten the screws. Note: Do not loosen all four screws simultaneously to ensure that the vertical angular alignment is not altered. G 31. Loosen the screws on the other side of the motor, install the shims, and tighten the screws. 7-8 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS G 32. Repeat the procedure until the vertical parallel misalignment is less than 0.015 in. Horizontal Angular Alignment G 33. Position the coupling halves so that the soapstone marks are aligned at the 9-o'clock position. G 34. Measure the B1 distance at the 9 o'clock position with a dial caliper as shown in Figure 7-9. B1 distance at the 9-o'clock position: Figure 7-9. Horizontal angular alignment. G 35. Position the coupling halves so that the soapstone marks are aligned at the 3-o'clock position. G 36. Measure the B2 distance at the 3-o'clock position. B2 distance at the 3-o'clock position: G 37. Calculate the horizontal angular misalignment by subtracting the smallest distance from the larger. Note the position at which the larger distance was measured. Horizontal angular misalignment: Position of the larger distance: INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 7-9 SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS G 38. Determine in which direction the motor must be rotated. Rotate the motor in the counterclockwise direction if the largest distance was measured at the 9-o'clock position. Otherwise, rotate the motor in the clockwise direction. G 39. Loosen the screws, rotate the motor in the required direction, and tighten the screws. G 40. Recalculate the horizontal angular misalignment, and repeat the procedure until it is less than 0.030 in. Horizontal Parallel Alignment G 41. Position the coupling halves so that the soapstone marks are aligned at the 9-o'clock position. G 42. Lay a straightedge on the soapstone marks and measure the gap using a feeler gauge as shown in Figure 7-10. Gap: Figure 7-10. Horizontal parallel alignment. Note: The measured gap corresponds to the motor's required displacement. G 43. Loosen the four motor screws, and shift the motor in the required direction. G 44. Repeat the procedure until the horizontal parallel misalignment is less than 0.015 in. 7-10 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  SHAFT ALIGNMENT AND FLEXIBLE COUPLINGS G 45. Ask the instructor to check your work. G 46. Do not disassemble the setup now if you expect to be the next team to use the universal base. If not, disassemble the setup and return the components to the storage location. Name: Date: Instructor's approval: INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 7-11 7-12 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  8 SHAFT ALIGNMENT AND RIGID COUPLINGS Rigid shaft couplings are used to join lengths of shaft of equal or different diameter. The main use is to extend the length of a shaft. It is rarely used to connect a prime mover directly to a load. A rigid sleeve coupling is shown in Figure 8-1. Figure 8-1. Rigid coupling. Unlike flexible shaft couplings, rigid shaft couplings do not allow errors in alignment, which may cause premature failure of bearings or shafts. Rigid shaft couplings are installed after the shafts have been aligned. A straightedge and feeler gauge are used to measure and adjust parallel and vertical alignment. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 8-1 8-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  8 SHAFT ALIGNMENT AND RIGID COUPLINGS OBJECTIVES In this job, you will perform a shaft alignment and install a rigid coupling. EQUIPMENT REQUIRED C Universal Base Assembly, model 46603 C Motor Package, model 46609 C Couplings – Shafts Panel, model 46610 C Pillow Block Bearings Panel, model 46611 C Test/Measurement Package, model 46630 C Tool Box Component Package, model 46631 SAFETY PROCEDURE Before proceeding with this job, complete the following check list. G You are wearing safety glasses. G You are wearing safety shoes. G You are not wearing anything that might get caught such as a tie, jewelry, or loose clothes. G If your hair is long, tie it out of the way. G The working area is clean and free of oil. G The floor is not wet. G Your sleeves are rolled up. PROCEDURE Lockout/Tagout Procedure G 1. Set the disconnecting switch to OFF. G 2. Write your name on a tag, and install it in the lockout device. G 3. Lock the disconnecting switch with the lockout device. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 8-3 SHAFT ALIGNMENT AND RIGID COUPLINGS G 4. Lock the lockout device with your padlock. G 5. Ask the instructor and each teammate to install their own padlocks in the lockout device. Note: The universal base should be set up from Job Sheet 7. Repeat Job Sheet 7 if necessary. Universal Base Setup G 6. Loosen the pillow block bearing setscrews and slide the shaft away from the motor. G 7. Remove the flexible jaw coupling halves, insert, and keys from the two shafts. Keep the rest of the setup intact. G 8. Slide the sleeve coupling on the shaft supported by the pillow block bearings. Vertical Angular Alignment G 9. Adjust the gap between the ends of the shafts to approximately 0.125 in. G 10. Line up the shaft keyseats and position them at the 9-o'clock position. G 11. Lay a straightedge on the top of the shafts and measure the gap at two points using a feeler gauge as shown in Figure 8-2. Mark the position of the two points with a soapstone marker. 8-4 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  SHAFT ALIGNMENT AND RIGID COUPLINGS Figure 8-2. Vertical angular alignment. Gap at point 1: Gap at point 2: G 12. Calculate the vertical angular misalignment by subtracting the smaller gap from the larger. Note the position at which the larger gap was measured. Vertical angular misalignment: Position of the larger gap: G 13. Record the distance between the measurement points (soapstone marks) along the shaft. Distance between measurement points: G 14. Calculate the shim ratio using the following formula: where Sr is the shim ratio; L1 is the distance between the slots of the motor base, in inches; L2 is the distance between the measurements points in inches. Shim ratio: INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 8-5 SHAFT ALIGNMENT AND RIGID COUPLINGS G 15. Calculate the required shim thickness using the following formula: where St is the shim thickness in inches; Sr is the shim ratio; Vam is the vertical angular misalignment in inches. Shim thickness: G 16. Determine if the front or the rear of the motor must be shimmed. Side to be shimmed: G 17. Loosen the screws on the determined motor base side and install the shims. Note: An equal thickness of shims must be installed under the two front or rear motor screws to raise it evenly. G 18. Measure the gaps at point 1 and 2, and calculate the vertical angular misalignment. Gap at point 1: Gap at point 2: Vertical angular misalignment: Vertical Parallel Alignment G 19. Measure the gap at one point between the shafts, using a straightedge and a feeler gauge. G 20. Add shims with a total thickness equivalent to the gap under the four screws of the motor plate. Horizontal Alignment G 21. Line up the shaft keyseats and position them at the 12-o'clock position. G 22. Lay a straightedge on the side of the shafts at the 3-o'clock position. G 23. Loosen the four motor screws, and adjust the motor position until there is no gap between the straightedge and the shafts. 8-6 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  SHAFT ALIGNMENT AND RIGID COUPLINGS G 24. Tighten the motor screws. Sleeve Coupling Installation G 25. Install a key on both shafts. Make sure they are in line with the end of each shaft. G 26. Slide the sleeve coupling along both shafts and make sure there is no interference at any point. G 27. Tighten the coupling setscrews on the keys. G 28. Ask the instructor to check your work. G 29. Disassemble the setup and return the components to the storage location. Name: Date: Instructor's approval: INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 8-7 8-8 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  9 MOTOR SOFT FOOT DETECTION AND CORRECTION Soft Foot A soft foot exists when a machine foot is not sitting flat on its base as shown in Figure 9-1. This condition can be caused by a damaged base, uneven or bent feet, bent or dirty shims, and rust. A soft foot can damage the bearings and seals, cause shaft misalignment, and make the coupling installation difficult. Figure 9-1. Motor soft foot. A soft foot can be detected with a feeler gauge under the machine feet or with a dial indicator installed on the machine feet. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 9-1 9-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  9 MOTOR SOFT FOOT DETECTION AND CORRECTION OBJECTIVES In this job, you will detect and correct a simulated soft foot condition on a motor. EQUIPMENT REQUIRED C Universal Base Assembly, model 46603 C Motor Package, model 46609 C Test/Measurement Package, model 46630 C Tool Box Component Package, model 46631 SAFETY PROCEDURE Before proceeding with this job, complete the following check list. G You are wearing safety glasses. G You are wearing safety shoes. G You are not wearing anything that might get caught such as a tie, jewelry, or loose clothes. G If your hair is long, tie it out of the way. G The working area is clean and free of oil. G The floor is not wet. G Your sleeves are rolled up. PROCEDURE Lockout/Tagout Procedure G 1. Set the disconnecting switch to OFF. G 2. Write your name on a tag, and install it in the lockout device. G 3. Lock the disconnecting switch with the lockout device. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 9-3 MOTOR SOFT FOOT DETECTION AND CORRECTION G 4. Lock the lockout device with your padlock. G 5. Ask the instructor and each teammate to install their own padlocks in the lockout device. Universal Base Setup G 6. Fix two T-slotted extrusions on the universal base as shown in Figure 9-2. Figure 9-2. Universal base setup. G 7. Install the variable speed motor on the T-slotted extrusions. G 8. Place a 0.030-in. shim under three of the four screws of the motor mounting base to simulate a soft foot condition. G 9. Tighten the four screws of the motor base. 9-4 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  MOTOR SOFT FOOT DETECTION AND CORRECTION Dial Indicator Installation G 10. Get the flat bar and dial indicator from the tool box. G 11. Mount the indicator on its base as shown in Figure 9-3. Figure 9-3. Dial indicator mounted on its base. G 12. Install the flat bar next to the motor using a T-nut and a 5/16-18 x 3/4-in. HHCS. G 13. Install the indicator and base assembly on the flat bar. G 14. Place the probe of the dial indicator next to a motor screw on the motor base as shown in Figure 9-4. Orient the probe so that it is as perpendicular to the base plate as possible. Make sure the probe is touching the motor base plate. INTRODUCTION TO MECHANICAL DRIVE SYSTEMS 9-5 MOTOR SOFT FOOT DETECTION AND CORRECTION Figure 9-4. Soft foot detection using a dial indicator. G 15. Set the indicator to zero. G 16. Loosen the screw and measure the displacement on the dial indicator. Displacement: Note: If there is no displacement, there is no soft foot condition under this foot. G 17. Correct the soft foot by adding shims under the motor that exhibits a soft foot condition. G 18. Repeat the measurement for each foot. G 19. Ask the instructor to check your work. G 20. Disassemble the setup and return the components to the storage location. Name: Date: Instructor's approval: 9-6 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  Appendix A Unit Conversion Table CONVERSION SI UNITS IMPERIAL UNITS FACTOR ACCELERATION centimeter per square second, cm/s2 0.3937 inch per square second, in./s2 2 meter per square second, m/s 3.2808 foot per square second, ft/s2 AREA square millimeter, mm2 0.0016 square inch, in2 square centimeter, cm2 0.1550 square inch, in2 square meter, m2 10.7639 square foot, ft2 FLOW liter per minute, L/min 0.0351 cubic foot per minute, ft3/min 3 cubic centimeter per minute, cm /min 0.0021 cubic foot per hour, ft3/h FORCE newton, N 0.2248 pound-force, lbf LENGTH millimeter, mm 0.0394 inch, in. centimeter, cm 0.3937 inch, in. meter, m 39.3701 inch, in. meter, m 3.2808 foot, ft MASS gram, g 0.0353 ounce, oz kilogram, kg 2.2046 pound, lb POWER watt, W 0.0013 horsepower, hp PRESSURE kilopascal, kPa 0.1450 pound force per square inch, lbf/in2 TORQUE newton meter, NAm 0.7376 pound-force foot, lbfAft newton meter, NAm 8.8507 pound-force inch, lbfAin VELOCITY centimeter per second, cm/s 0.0328 foot per second, ft/s millimeter per second, mm/s 0.0394 inch per second, in./s VOLUME cubic centimeter, cm3 0.0610 cubic inch, in.3 3 cubic meter, m 35.3147 cubic foot, ft3 How to use: Imperial units = SI units × conversion factor SI units = Imperial units ÷ conversion factor INTRODUCTION TO MECHANICAL DRIVE SYSTEMS A-1 A-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  Appendix B Post-Test 1. What does the meter indicate on the control panel? a. The voltage at the Motor outlet on the side of the control panel b. The voltage at the Motor outlet on the universal base c. The current delivered at the Motor outlet on the universal base d. The current delivered at the Motor outlet on the side of the control panel 2. To which position should the Output Voltage selector be set when using the constant speed motor on the universal base? a. Fixed b. Variable c. Any position is correct d. It depends on the use of the motor. 3. What is the use of the emergency button on the Start/Stop station? a. Controls the motors mounted on the universal base b. Produces an emergency noise c. De-energizes the Motor outlet on the universal base d. De-energizes the Motor outlet on the side of the control panel 4. Who must install a padlock on the lockout device? a. Each person involved in the job b. Only one of the person involved in the job c. The instructor only d. It is never mandatory to install a padlock. 5. When should the safety panels be installed? a. When there is an obvious risk of injury b. When the constant speed motor is used c. When asked by the instructor d. Before any setup is powered 6. What does a photo-reflective tachometer measure? a. The amount of light reflected by an object b. The current in a component c. The voltage in a component d. The angular velocity of a rotating component INTRODUCTION TO MECHANICAL DRIVE SYSTEMS B-1  Post-Test (cont'd) 7. What is a prony brake used for? a. Measure the input power of a prime mover b. Provide a means for applying an adjustable load torque to the output shaft of a prime mover c. Brake a motor until it stops completely d. Measure the current consumed by a motor when it stops 8. Where should a setscrew be tightened on a shaft? a. Only on a key b. On the flat surface of the shaft or on a key c. Directly on the shaft keyseat d. Preferably on the round portion of the shaft 9. What type(s) of coupling(s) can compensate for slight errors in shaft alignment? a. Flexible couplings only b. Rigid and flexible couplings c. Rigid couplings only d. Any existing type 10. What are the two basic types of shaft misalignment? a. Horizontal angular and parallel b. Angular and linear c. Parallel and angular d. Vertical angular and horizontal angular B-2 INTRODUCTION TO MECHANICAL DRIVE SYSTEMS  We Value Your Opinion! Your comments will allow us to produce better manuals and develop new systems in order to better meet the needs of our users. Please contact us by Email at: [email protected] For further information, visit our Web site at www.labvolt.com