MONARCH INSTRUMENT EXAMINER 1000 Instruction Manual

MONARCH INSTRUMENT
Instruction Manual
EXAMINER 1000
MONARCH INSTRUMENT
15 Columbia Drive Amherst, NH 03031 USA Phone: 603-883-3390 Fax: 603-886-3300 www.monarchinstrument.com e-mail: sales@monarchinstrument.com
Printed in the U.S.A. © Monarch Instrument 2001 all rights reserved
1071-4400-112
EXAMINER 1000 SPECIFICATIONS
Vibration Sensor: Piezoelectric accelerometer 100 mV/g with magnetic base, probe
and 5 foot cable to BNC Display: LCD 3.5 digit , measurement, hold, low battery indicator Measurement Acceleration 0.01-19.99 g (RMS) Range: Velocity 0.01-19.99 in/sec., 0.1-199.9 mm/sec (RMS)
Envelope 0.01-19.99 ge (peak) Frequency Range: Overall 10 Hz - 10 kHz
Envelope 0.5 kHz-10 kHz Output: Sensor Excitation: 12 Vdc @ 2 mA (BNC)
Audio Out: 3.5 mm mini plug; 250 mW into 8 ohms, 150 mW into
32 ohms; Adjustable volume control with off position Power: (2) “AA” cells Operating Time: 20 hours continuous without headphones Weight: Instrument: 7 oz. (0.19 kg); Complete Kit: 2.85 lb (1.30 kg) Dimensions: 6.3 x 3.3 x 1.25” (152 x 83 x 32 mm) Operating conditions: -14° to 122°F (-10° to 50°C)
ISO 2372 (10816) Standards provide guidance for evaluating vibration severity in machines operating in the 10 to 200 Hz (600 to 12,000 RPM) frequency range. Examples of these types of machines are small, direct-coupled, electric motors and pumps, production motors, medium motors, generators, steam and gas turbines, turbo-compressors, turbo-pumps and fans. Some of these machines can be coupled rigidly or flexibly, or connected through gears. The axis of the rotating shaft may be horizontal, vertical or inclined at any angle. Use the chart below combined with additional factors described in this manual to judge the overall vibration severity of your equipment.
VIBRATION SEVERITY PER ISO 2372 (10816)
Vibration Velocity Vrms
good
satisfactory
unsatisfactory
unacceptable
Machine Class I Class II Class III Class IV
small medium large rigid large soft
in/s mm/s foundation foundation
0.01 0.28
0.02 0.45
0.03 0.70
0.04 1.10
0.07 1.80
0.11 2.80
0.18 4.50
0.28 7.00
0.44 11.0
0.71 18.0
1.10 28.0
MONARCH INSTRUMENT
Service Policy, Warranty, Disclaimer and Limit of Remedies
Except for the limited warranty described below, there are no warranties, expressed or implied, including but not limited to, the implied warranties of merchantability and fitness for a particular purpose: all such warranties are expressly and specifically dis­claimed.
EXAMINER 1000 is guaranteed free from defects in material and workmanship. Me­chanical components, transducers, and cable assemblies are guaranteed for a period of (90) days. Electronic components are guaranteed for a period of (12) months. The warranty period begins on the date the products are shipped from the Monarch Instru­ment factory or an Authorized Distributor.
This warranty does not extend to units that have been misused, altered, or repaired without manufacturer’s authorization. Defects or failures experienced during the war­ranty period will be corrected at no charge at the manufacturer’s facility. If, upon examination, it is found that the defect is not within the scope of this warranty, an estimate of repair charges and a request for authorization to proceed with the repair will be submitted, along with a statement of the reasons the repairs are not considered to be covered by the warranty.
This warranty does not extend to system components such as transducers, headphones and cable assemblies manufactured by others. Warranty for these components will be their manufacturer’s standard.
Manufacturer’s liability under this warranty is limited to repair or replacement of any defective instrument at the discretion of the manufacturer. In the event that any of the above limitations are held unenforceable, our liability to you shall not exceed the purchase price paid for the product, regardless of the claim. Because of the diverse ways that the product can be used, you are advised to test the product for suitability of use for your purposes prior to relying on it.
MONARCH INSTRUMENT
15 Columbia Drive Amherst, NH 03031 USA Phone: 603-883-3390 Fax: 603-886-3300 www.monarchinstrument.com e-mail: sales@monarchinstrument.com
OPERATING THE EXAMINER 1000
Overview ........................................................................... 1
Controls and Functions........................... ........................... 1
Rear Panel, Batteries and Connections ............................. 2
Parts of the System ........................................................... 3
Overview of Data Collection Procedure.............................. 3
APPLYING THE EXAMINER 1000
What is Predictive Maintenance? ....................................... 4
Benefits of Predictive Maintenance .................................... 4
Why Measure Vibration? .................................................... 5
Selecting Machinery & Measurements................................ 6
Selecting Measurement Types ........................................... 7
Getting Started in your Plant............................................... 8
Establishing a Data Collection Route.................................. 9
What are you Measuring? .................................................. 10
Measurement Techniques .................................................. 11
Evaluating overall Vibration Measurements ........................12
Evaluating Acceleration Envelope Measurements...............13
GLOSSARY ........................................................................14
TABLE OF CONTENTS
TABLE OF CONTENTS
GLOSSARY (for vibration purposes)
Piezoelectric A material in which electrical properties change when subjected
to force.
Process Measurements Variables such as temperature, pressure, speed and
flow used to assess internal conditions of efficiency.
Radial Direction perpendicular to the shaft centerline. Repeatability A measure of the deviation between successive measurements made
under the same conditions.
RMS Peak Vibration x .707. ( in/s or mm/s)
Rolling Element Bearing A bearing consisting of balls or rollers operating be-
tween fixed and rotating races.
Route A sequence of measurements arranged for convenience
during acquisition.
Sensitivity Used to describe a transducer’s electrical output for a unit varia-
tion of the mechanical quantity measured.
Stress Force per unit area Synchronous Frequency components that are an integer multiple of
running speed.
Transducer A system consisting of a sensor and signal conditioner to convert
a physical quantity into an output for display, monitoring and analysis.
Transmission Path The path from source (excitation) to sensor. Trending The plot of a variable over time used as an indicator of change. Velocity A vector quantity of the time rate change of displacement.
15
Vibration Conversions
D = 19.10 x 103 x (V/F) D = 70.4 x 106 x (A/F2)
V = 52.36 x 10-6 x D x F V = 3.68 x 103 x (A/f)
A = 14.2 x 10-9 x D x F
2
A = 0.27 x 10
-3
x V x F
where: D = Displacement (mils peak-to-peak)
V = Velocity (in/s zero-to-peak) A = Acceleration (in/s2 zero-to-peak) F = Frequency (cpm)
OPERATING THE EXAMINER 1000
Overview
The EXAMINER 1000 is designed in conjunction with vibration limits estab­lished in ISO Standards 2372(10816)/3945 to help you detect signs of malfunction or changes in rotating machinery during operation. This is accomplished with overall vibration (ISO VIB) and envelope measurements. Problems with bearings occur when there is a microscopic crack or flaw or when there is a breakdown in lubrica­tion which leads to metal-to-metal interaction. The EXAMINER 1000 is designed to detect flaws or a lack of lubrication in bearings and gears at an early stage by measuring the high-frequency impacts through acceleration envelope methods.
Vibration measurements are made by pressing the accelerometer sensor against designated Measurement Points on your equipment with either the stringer probe or with the magnetic base.
Controls and Functions
ON/SELECT Button - Press this button to turn power on. Power automatically turns off after ten minutes of non-use. After turning the EXAMINER “on”, press the ON/SELECT button again to select the measurement type. Pressing and hold- ing the ON/SELECT button while collecting data will HOLD the display value, indicated by the word “HOLD” in the display. To release from HOLD mode, press the ON/SELECT button again.
DISPLAY- The digital display shows the numerical value of the measurement. An arrow indicates the measurement type selected. The units of vibration are auto­matically displayed as the type of measurement is selected. The user may work in either metric or imperial units in the V-velocity mode.
1
Type of Measurement
Value of Measurement
Units of Measure
0.09
g GE in/s mm/s
V
A
E
LoBat
HOLD
Low Battery Indicator
Type of Measurement Indicator
Hold Reading Indicator
GLOSSARY (for vibration purposes)
Acceleration A vector quantity that specifies time rate of change of velocity.
Expressed in either g’s or m/sec2 where 1 g = 386.1 in/sec2 and
9.8066 m/sec2.
Acceleration Enveloping A high-frequency, filtered data collection method ex-
pressed in ge.
Accelerometer A transducer which converts acceleration motion in to an
electrical output.
Amplitude The magnitude of vibratory motion. Can be measured as peak-to-
peak, zero-to-peak, or RMS.
Axial The direction parallel to the axis of rotation. Baseline Recorded values taken when a machine is know to be good. The
standard which all additional readings will be compared to.
CPM Unit of frequency measurement-cycles per minute. Displacement A vector quantity specifying the change of position of a body mea-
sured from the resting position.
Dynamic Force A force that varies with time. Force Energy applied to a mass producing a deflection (static force) or
motion (dynamic force).
Frequency The repetition rate of a periodic event, expressed in cycles per
second (Hz), CPM, RPM, or multiples of running speed (orders).
g’s Units of acceleration produced against the force of gravity.
(1g=32.1739 ft./sec/sec; 1g=9.8066 m/sec/sec)
Gear Mesh Frequency A frequency generated by a gear. Defined as the number
of gear teeth on a gear times its shaft-rotating frequency.
Hertz (Hz) A unit of frequency measurement, cycles per second.
High-pass Filter A filter that allows only those components above a selected fre-
quency to pass.
Integration The time-based process of converting acceleration and velocity to
velocity or displacement.
in/sec, ips Abbreviations for inches per second, a measure of velocity. Mass The measure of body resistance to acceleration. Proportional to,
but not equal to, weight (mass = weight/gravity).
Measurement Point A location on a machine or component where all subsequent
measurements should be made for accurate comparison.
Mechanical Impedance Ratio of applied force to resulting velocity during
simple harmonic excitation.
Overall The amplitude of vibration within a specified frequency range. Peak Value The absolute value zero to the maximum excursion on a dynamic
waveform. Also true peak and zero-to-peak.
Periodic Monitoring Measurements recorded at intervals of time.
14
2
BATTERY COMPARTMENT
Contains two “AA” alkaline batteries.
REAR PANEL CONNECTIONS
AUDIO OUT SENSOR IN
CONNECTIONS
QUICK REFERENCE INSTRUCTION PANEL
PRODUCT SERIAL NUMBER
AUDIO OUT
1/8” (3.5 mm) stereo mini plug
SENSOR INPUT
BNC Connector output 12 vdc @ 2 mA
VOLUME
CONTROL
TOP VIEW
E X A M I N E R
1 0 0 0
VIBRATION METER
ELECTRONIC STETHOSCOPE
REFER TO OPERATORS MANUAL
FOR INSTRUCTIONS
CONNECTIONS
SENSOR IN AUDIO OUT
Measurement Types Units V velocity mm/s in/s A acceleration g E envelope ge
Monarch Instrument 15 Columbia Drive Amherst, NH 03031 USA
Trend Comparison
The most efficient and reliable method of evaluating vibration severity is to com­pare the most recent reading against previous readings for the same measurement Point, allowing you to see how the Point’s vibration values are “trending” over time. This trend comparison between present and past readings is easier to analyze when the values are plotted in a “trend plot”. A trend plot displays current and past values plotted over time. Measurement records should also include a baseline (known good) reading. The baseline value may be acquired after an overhaul or when other indicators show that the machine is running well. Subsequent measurements are compared to the baseline to determine machinery changes.
Comparison with Other Machinery
When several similar machines are used under the same operating conditions, evalu­ation can be carried out by measuring all machines at the same Points and compar­ing the results.
Evaluating Acceleration Envelope Measurements
Use the same techniques of comparison as for Overall Vibration readings. Remem­ber, acceleration envelope is an advanced “early warning” of a developing prob­lem. High values do not necessarily indicate bearing failure. They can also indicate:
A. Lack of lubrication or decreasing oil viscosity due to high bearing tem-
perature caused by overload or external heat source.
B. Breaking of the lubricant film by excessive imbalance, misalignment,
or housing deformation. Loss of boundary lubrication. C. A rubbing seal or cover. D. Gear mesh interaction (bad lubrication, defects) E. Dirt or particles in the lubricant, or a seal or filter problem.
Use trend Comparison similar to overall vibration to establish severity levels.
Accelerating Envelope readings tend to decrease as Overall Vibrations readings increase. This happens when the defect in the bearing is becoming more severe and the frequency it generates becomes lower which makes it better read with the Velocity-type readings.
Audio Comparison with Other Bearings on the Same Machinery
When several bearings are used under the same operating conditions, evaluation can be carried out by listening to the audio signals to determine changes. This method will help to locate the defective bearing quickly. Measure all machines at the same Points and compare the results. Listen for increases in signal and for “clicking” patterns which indicate wear.
13
Overview of Data Collection Procedure
1. Press the ON/SELECT button.
2. Press the ON/SELECT button again to select the desired measurement type. Place the accelerometer sensor on the machinery Measurement Point (use proper probe technique as discussed on the following pages).
3. Wait for the reading to stabilize, then press and hold the ON/SELECT button to “HOLD” the measurement. Indicated by HOLD in the display.
4. Adjust headphones volume level and listen for any distinct patterns or noises.
5. Record the measurement value in your Machinery Data Worksheet.
6. To release the HOLD function, press ON/SELECT again.
7. Repeat the above steps for each Measurement Point.
3
Parts of the System
EXAMINER 1000 METER
ACCELEROMETER WITH CABLE
HEAD PHONES
MAGNETIC BASE
STINGER PROBE
HOLSTER
ON-TIME SOFTWARE AND OWNERS MANUAL (optional)
Evaluating the Overall Vibration Measurements
Three general principles are commonly used to evaluate your vibration measure­ment values: ISO 2372 (10816) Standard Comparison - Compare values to the limits estab-
lished in the ISO 2372 (10816) Standard.
Trend Comparison - Compare current values with values of Baseline for the same
Points over a period of time.
Comparison with Other Machinery - Measure several machines of a similar type
under the same conditions and judge the results by mutual comparison.
If possible, you should use all three comparisons to evaluate your machinery’s condition. ISO 2372 (10816) and trend comparisons should always be used.
ISO 2372 (10816) Standard Comparison
The ISO 2372 (10816) Standards provide guidance for evaluating vibration sever­ity in machines operating in the 10 to 200 Hz (600 to 12,000 RPM) frequency range. Examples of these types of machines are small, direct-coupled, electric motors and pumps, production motors, medium motors, generators, steam and gas tur­bines, turbo-compressors, turbo-pumps and fans. Some of these machines can be coupled rigidly or flexibly, or connected through gears. The axis of the rotating shaft may be horizontal, vertical or inclined at any angle. Machinery class designations are:
Class l
Individual parts of engines and machines, integrally connected with the complete machine in its normal operating condition. (Production electrical motors of up to 20 HP (15 kW) are typical examples of machines in this category.)
Class ll
Medium-sized machines typically, electric motors with 20 to 75 HP (15-75 kW) without special foundations, rigidly mounted engines, or machines on special foun­dations up to 400 HP (300 kW).
Class lll
Large prime movers and other large machines with rotating masses mounted on rigid and heavy foundations which are relatively stiff in the direction of vibration measurement.
Class lV
Large prime movers and other large machines with rotating masses mounted on foundations which are relatively soft in the direction of vibration measurement (for example, turbo-generator sets, especially those with lightweight ub-structures).
Note: These ISO 2372 (10816) Standard classes do not apply to prime movers or driven equipment in which the major working components have a reciprocating motion.
12
What Is Predictive Maintenance?
Predictive Maintenance can be defined as collecting information from machines as they operate to aid in making decisions about their health, repair and possible im­provements in order to reach maximum runability, before any unplanned break­down. Machinery maintenance has evolved because of the demands to become more profitable through reduced maintenance costs. Below is the progression of these maintenance philosophies:
• Break Down Maintenance
• Preventive Maintenance
• Predictive Maintenance
Break Down Maintenance occurs when repair action is not taken on a problem
until the problem results in the machines failure. Run to failure problems often cause costly secondary damage along with expenses resulting from unplanned down­time and unplanned maintenance.
Preventive Maintenance occurs when a machine, or parts of a machine, are over­hauled on a regular basis regardless of the condition of the parts. While better than run to failure, preventive maintenance results in excessive downtime due to unnec­essary overhauls and the excessive costs of replacing good parts along with worn parts.
Predictive Maintenance is the process of determining the condition of machinery as it operates, to predict and schedule the most efficient repair of problem compo­nents prior to failure. Predictive Maintenance not only helps plant personnel elimi­nate unplanned downtime and the possibility of catastrophic failure, but allows them effectively order parts, schedule manpower, and plan multiple repairs during scheduled downtime.
Benefits of Predictive Maintenance
Documented experience proves that plants which establish a predictive mainte­nance program are able to:
• Improve Machinery Reliability-reduced “unplanned failures”
• Reduce Maintenance Costs-knowing the exact problem to fix
• Increase Production-optimize machinery capabilities
• Lower Energy Consumption- less vibration usually means less friction
• Extend Bearing Service Life- reduce vibration and lubrication failures
• Improve Product Quality- where less vibration improves finish
The benefits are numerous and will vary depending upon the implementation of your Predictive Maintenance Program.
411
Measurement Techniques
In general, vibration of anti-friction bearings is best monitored in the load zone of the bearing. Equipment design often limits the ability to collect data in this zone. Simply select the measurement Point which gives the best signal. Avoid painted surfaces, unloaded bearing zones, housing splits, and structural gaps. When mea­suring vibration with a hand-held sensor, it is very important to collect consistent readings, paying close attention to the sensor’s position on the machinery, the sensor’s angle to the machinery, and the contact pressure with which the sensor is held on the machinery.
• Location - always collect at the same point on the machine. Mark loca­tions.
• Position - Vibration should be measured in three directions: A axial direction H horizontal direction V vertical direction
Angle - Always perpendicular to the surface (90o +10o).
• Pressure - Even, consistent hand pressure must be used (firm, but not
so firm as to dampen the vibration signal). For best results use the magnetic base. If using the stinger/probe is the only method available to collect data, it is best to use a punch to mark the location for the probe-tip to ensure a consistent coupling to the housing.
Optimum Measurement Conditions
Perform measurements with the machine operating under normal conditions. For example, when the rotor, housing, and main bearings have reached their normal steady operating temperatures and with the machine running under its normal rated condition (for example, at rated voltage, flow, pressure and load). On machines with varying speeds or loads, perform measurements at all extreme rating condi­tions in addition to selected conditions within these limits. The maximum mea­sured value represents the vibration severity.
load zone
Magnetically Mounted Vibration Sensor
Stinger Mounted Vibration Sensor
5
Why Measure Vibration?
Vibration is considered the best operating parameter to judge dynamic conditions such as balance (overall vibration), bearing defects (enveloping) and stress applied to components. Many machinery problems show themselves as excessive vibra­tion. Rotor imbalance, misalignment, mechanical looseness, structural resonance, soft foundation, and gearmesh defects are some of the defects that can be measured by vibration. Measuring the “overall” vibration of a machine, a rotor in relation to a machine or the structure of a machine, and comparing the measurement to its normal value (norm) indicates the current health of the machine.
The EXAMINER 1000 measures the vibration of a machine while it is operating. Trending these measurements shows how a machine’s condition changes over a period of time. Analyzing these, along with other measurements, provide insight into the condition of the machine and which components may be wearing or fail­ing. How to best monitor a machine’s condition requires one to know which mea­surements to take and where and how to take them. Sensors are placed at strategic Points on the machinery to monitor the machine’s condition.
The EXAMINER 1000 processes the accelerometer’s mechanical vibration en- ergy into an electrical signal and displays the measurement value in numerical form for evaluation. Commonly measured physical characteristics in Predictive Maintenance are:
• Vibration (as explained above)
• Temperature
• Oil Analysis
Temperature
As a bearing fails, friction causes its temperature (or its lubricant’s temperature) to rise. While trending a bearing if the temperature rises followed by a vibration in­crease, then it is safe to conclude their was a loss of lubrication which induced the mechanical failure. If vibration increased first, followed by increased temperature readings then a mechanical defect caused the lubrication failure.
Lube Oil Analysis (Ferrography) Monitoring oil condition warns of an increase in foreign substances, such as water, which can degrade the lubricating properties of the oil and cause bearing failures. It also detects the presence of metallic particles carried into the oil stream. These metallic particles are analyzed to determine which part of the machine is wearing and how fast. Lubrication analysis is the earliest warning of a developing problem. Lube oil testing results can be trended with On-Time software.
What are you Measuring?
Vibration is the behavior of a machine’s mechanical components as they react to internal or external forces. Since most rotating machinery problems show them­selves as excessive vibration, we use vibration signals as an indication of a machine’s mechanical condition. Also, each mechanical problem or defect generates vibra­tion in its own unique way. We therefore analyze the “type” of vibration to iden­tify its cause and take appropriate repair action. With overall vibration monitoring (VIB ISO) using the Examiner 1000, analysis of the cause of excess vibration relates to the monitoring equipment’s probe position; either horizontal, vertical, or axial.
Horizontal - Typically, unbalanced shafts tend to cause excess radial (horizontal and vertical) vibrations, depending on the machine support design. Vertical - Excessive vertical vibration can indicate mechanical looseness as well as imbalance. Axial - Excessive axial vibration is a strong indicator of misalignment. It’s important to note that these are general guidelines and that knowledge of your machinery and proper hand-held probe techniques are necessary to accurately ana­lyze the cause of excessive vibration.
Multi-Parameter Monitoring
Using different measurement types to monitor your machinery for changes. This allows for early detection of specific machinery problems that may not show under normal overall vibration monitoring. For example, if a rolling element bearing has a defect on its outer race, each roller will strike the defect as it goes by and cause a small, repetitive vibration signal. However, this vibration signal is of such low amplitude that under normal overall vibration monitoring, it is lost in the machine’s rotational and structural vibration signals. Acceleration Enveloping can measure these signals better than overall readings. Use both measurement types for bear-
ings and gearboxes. As ENV values begin to decrease, rely on VEL readings.
Overall Vibration Monitoring -Monitors normal, low frequency machine vibra-
tion. Detects rotational and structural problems like imbalance, misalignment, and mechanical looseness.
Enveloping - Amplifies high-frequency, repetitive bearing and gear mesh vibra­tion signals for early detection of bearing problems, but does not detect non-repetitive rotational or structural events like imbalance, misalignment, and looseness. Pro­vides earliest detection of high frequency metal-to-metal contact or poor lubrica­tion in problem bearings.
10
6
Selecting Machinery and Measurements
Maintenance personnel have always made visual and hands-on inspections of their machinery on a periodic basis. Systematic data collection and trending allows for recall and comparison of events over time but is not a replacement for good main­tenance practices. Collecting machinery data is an aid to the maintenance profes­sional, which is used in addition to good maintenance practices.
Selecting and Classifying Machinery
Setting up an effective Predictive Maintenance Program requires a careful study of the needs of the plant. It is necessary to know each machine and its response to change. The following is an example of machinery classification:
Critical Machines expensive premium equipment, generally >500 HP. Usually less than 5% of all plant equipment. Maintenance dollars per horsepower per year average $11.00. This category of equipment is very well maintained and moni­tored. Continuous monitoring systems are better suited for this type of equipment.
Essential Machines medium size equipment, 100-500 HP. This group may be 30­40% of all the equipment in the plant. Maintenance costs can average $22.00 per horsepower per year. Less attention is paid to these machines even though their repair costs can be as high as critical machines. Select some of these machines for your Predictive Maintenance Program.
Redundant Machines small redundant equipment usually < 100 HP. This group can be as much as 50% of all machines in a plant and yet they are usually ne­glected. By far the most expensive to maintain at $49.00/HP/year, this group will benefit the most from Predictive Maintenance practices. At many facilities, this group consumes 80% of the annual maintenance budget. If you want to have an immediate impact begin with these machines. Also include machines with known problems or a history of problems. Personnel Safety is always the first priority in
selecting machinery to monitor.
CRITICAL
ESSENTIAL
REDUNDANT
Machine Identification Water Pump #707
Machine Description AC motor 1800 RPM, flexible
coupling, 3 vane pump. CAUTION HOT WATER!!!
Date Point Direction Type Value
Jan 2 1999 A V V 0.06 in/s Jan 2 1999 A H V 0.04 in/s Jan 2 1999 A X V 0.03 in/s Jan 2 1999 B V V 0.07 in/s Jan 2 1999 B H V 0.05 in/s Jan 2 1999 B V Env 0.001 ge
Establishing a Data Collection Route
The Machinery Data Worksheet helps organize data for routine data collection. Vibration readings are taken on the Points (bearings) established in your route and recorded using your naming convention on the worksheet. Vibration, speed, tem­perature, pressure or any process data may be recorded using this type of system­atic approach.
Steps for Route collection
1. Determine the machines which require data collection.
2. Define each measurement type for data collection Points on each Machine. Several Points will have numerous readings i.e. VEL and ENV and Temp.
3. Establish a Route with the Machines grouped by physical location.
4. Walk the Route, collecting and recording data for each Point.
5. Transfer data values to your On-Time Trending software.
Recording Data for a Machine
234
5
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234
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234
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BCD
MOTOR PUMP
A
The vibration sensor is placed on each data col­lection Point. The Point, direction of the sensor and the value are re­corded on the Machinery Data Worksheet.
Point AVV is taken on the out­board end of the motor, in the ver­tical position with a velocity type reading.
AHV -Point A in the horizontal po­sition with a Ve­locity type.
9
example of Machinery Data Worksheet
Selecting Measurements
Establish measurement types that most accurately reflect the condition of the equip­ment. Different causes or “mechanisms” are acting on the machine; various types
of measurements have been developed to measure each type of mechanism. Those mechanisms are:
Stress
A force on the machine or components which deflects the part. Best mea­sured in Displacement. The Examiner 1000 does not measure Displace­ment as it is a very low vibration frequency, below 10 Hz (600 RPM).
Fatigue Repeated cycles of stress on a component. If you bend a part back and
forth enough times it will fatigue. As a general rule, fatigue failures result from vibration frequencies 10 -2000 Hz and Velocity measure­ments are used. Velocity will be the primary measurement taken.
Force Mass x acceleration. Measured in Acceleration. Acceleration is the rate
of change of velocity. Acceleration is used for high frequencies above 2000 Hz (120,000 RPM). Bearing defects and gearmesh frequencies are usually found in this range.
Impact forces The result of fatigue. Impact forces are cyclical events which can
be detected with Acceleration Enveloping. These are high fre­quency-low amplitude events and a filter in the EXAMINER 1000 is set at 10-30 kHz to measure them.
Types of Measurements in the EXAMINER 1000
Velocity- Good for frequency ranges 10-2000 Hz (600-120,000 RPM). Acceleration-used for higher frequencies or speeds above 2000 Hz (120,000 CPM). Acceleration Enveloping-uses a high pass filter to measure high-frequency, re-
petitive bearing and gearmesh vibration signals. Used for early detection of devel­oping bearing or lubrication problems. Use this type in combination with the other types to detect changes in machinery.
Select Measurement Intervals
Based on the classification of the machine, its repair history and the amount of data required for a detailed trend analysis. At the beginning of a Predictive Mainte­nance Program, collect data frequently to build a rapid history of each machine. Adjust your program as you go. If measurement results are indicating signs of
change, measurements should be performed more frequently.
7 8
Getting Started in Your Plant
Planning your work is very important to achieve success. The EXAMINER 1000 is an overall vibration meter and electronic stethoscope. It can be used as a stand alone device for the collection of vibration data for the purposes of trending or as a diagnostic instrument used to troubleshoot machinery defects. In order to setup a trending program you must collect data on the same point with the same measure­ment type at a defined interval. The Machinery Data Worksheet allows for record keeping of collected data. The EXAMINER may be used with the On-Time soft­ware to store data and perform trend analysis. REPEATABILITY IS REQUIRED
FOR ACCURATE TRENDING.
Establish a standard naming convention so you can communicate your results to the rest of maintenance. Vibration readings are taken on the bearing caps or as close to the bearings as possible. Always collect data the same way, at the same point on the machine each time.
Horizontal
Axial
Direction for placing the Sensor
For Vertical and Horizontal readings, the sensor is placed in a radial position.
Also establish a starting point for each machine. Begin from the OUTBOARD END of the DRIVE UNIT, calling this point A. Proceed to label Points (bearings) as needed until you have reached the outboard end of the driven unit.
POINT A
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234
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234
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234
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234
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234
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234
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BCD
MOTOR PUMP
Vertical
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