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Cygnus MINI ROV Operation Manual 

M4-CYGMINI-TSR-M-ENG_Iss 1 

 

Page 50 of 66 

13.

 

Care and Servicing 

Cleaning the Gauge 

 

After each submersion, and while the instrument is still 
assembled, wash the unit in fresh water and allow to dry   

 

To maintain the water-tight integrity of the assembly : the 
Gauge should be disassembled after every submersion, and 

the O-Rings should be replaced with new 

 

Clean the O-Ring grooves, and ensure that there are no 
particles remaining -  
a mild detergent may be necessary to remove grease from 
the O-Ring grooves   

 

Care should be taken not to allow water into the instrument 
body whilst cleaning   

 

Do not use solvents for cleaning 

 

Do not use any abrasive cleaner  

Use of O-Rings

 

 

When reassembling before a submersion: always replace both 

O-Rings with new, first ensuring that they are lubricated with 
Silicone grease 

 

To avoid the risk of a leak: prevent accidental re-use by 
destroying all used O-Rings after each submersion 

Data-link connector

 

 

Always apply a coating of Silicone grease to the pins of the 

data-link connector before insertion into the socket on the 
Gauge 

 

If the Gauge is to be stored without the cable assembly 
connected, it is essential that the Blanking plug is inserted in 
the socket instead 

 

The pins of the Blanking Plug should also be lubricated with 
Silicone grease 

 

Содержание MINI ROV

Страница 1: ...Cygnus MINI ROV Mountable and Topside Repeater Systems Operation Manual and Accessories List Doc No M4 CYGMINI TSR M ENG_Iss 1 August 2014 Mk4 Cygnus MINI ROV Gauges ...

Страница 2: ...exceed customer expectations in terms of performance reliability and safety Internal Systems Operate effective and safe working practices that comply with ISO 9001 2008 and EN ISO IEC 80079 34 and other applicable regulatory and statutory requirements Provide adequate resources to ensure product and service quality is maintained Set communicate and measure performance objectives and targets to pro...

Страница 3: ...ons to the Gauge 15 Power Supply 15 Data Output 15 Electrical connections to the Surface 16 Connection to a Computer 16 Connection to the ROV Craft 16 Custom Connection 16 Custom Display Software 16 Measuring Through a Water Gap 17 4 Displaying the Thickness Measurements 18 Data Logging 18 Video Overlay 18 5 Calibration 19 6 Using the TSR Remote Display Unit 20 Turning the Unit On 20 Changing the ...

Страница 4: ... CygLink Surveys and Data Logging 31 Editing the Survey Details 33 Editing the Survey Group Details 33 Producing a Survey Report Document 34 Logging Measurements Directly in CygLink 35 Linear or Grid Data Logging 35 Reference and Minimum Thickness Criteria 35 Pre Set Measurement Comments List 36 Adding Comments or Notes to a Measurement 36 CygLink Trouble Shooting 37 Connection Problems USB Driver...

Страница 5: ...s byte Structure 54 Data bytes Arrangement 54 Interpreting the Readings sent from the Gauge 55 16 Table of Sound Velocities 56 Reading Conversions 57 17 Part Number Accessories List 58 Software 58 Underwater Probes with 1 Metre Lead 58 Probe Spares and Membranes 59 Knurled Rings 60 Cables and Leads 60 Electronic Bodies Only 60 Miscellaneous Spares 60 18 Recycling and Disposal EC Countries 62 19 In...

Страница 6: ...Cygnus MINI ROV Operation Manual M4 CYGMINI TSR M ENG_Iss 1 Page 6 of 66 21 Index 66 ...

Страница 7: ...nd in air and is pressure tested to 500 metres water depth It is supplied with dedicated PC software for displaying and logging thickness readings at the surface The Gauge is supplied with one ultrasonic Probe The Probe type must be specified at the time of purchase of the Gauge Probes are not freely interchangeable please consult with Cygnus if you wish to use a different Probe with the Gauge The...

Страница 8: ...down within the metal shown on the left Each time an echo is reflected back down a small portion of the energy comes up through the coatings and is detected by the Probe which acts as a receiver e1 e2 and e3 The delay between echoes at the Probe face t2 and t3 is exactly equal to the time taken to pass through the metal twice therefore coatings such as paint are ignored and the measurement display...

Страница 9: ... environments Cygnus Ultrasonic thickness gauges are designed to be reliable and simple to use We have an unrivalled reputation in over 45 countries around the world CYGNUS Instruments Ltd Cygnus House 30 Prince of Wales Road Dorchester Dorset DT1 1PW England Tel 00 44 0 1305 265533 Fax 00 44 0 1305 269960 www cygnus instruments com sales cygnus instruments com CYGNUS Instruments Inc CYGNUS Singap...

Страница 10: ...2 Gauge Kit Contents 1 Cygnus MINI ROV Gauge Body 2 Nose Cone Torque Bar 3 Operation Manual CygLink Software on USB Flash Drive Not Shown 4 Bottle of Membrane Couplant 5 Carry Case 6 Test Lead 7 9 Way D Type Connector 8 Impulse Plug to Fly Leads 9 Impulse Blanking Plug 16 17 ...

Страница 11: ... and Warranty Letter 16 Probe Assembly including 17 Spare Membranes and Membrane Key 18 Sample Test Block Data Conversion Items Connection to USB is an RS232 to USB Adaptor as included in the main kit contents This USB to Serial Adaptor is used together with the RS422 to RS232 Converter as shown 1 RS 232 to USB Converter Module Cable 2 K3 RS 422 485 to RS 232 Converter Module 3 Connection from ROV...

Страница 12: ...lay Unit with Video On Screen Display OSD The Cygnus TSR Display unit with OSD is an Optional Accessory to the main Gauge Kit It is supplied with 1 Protective silicone sleeve 2 12V DC power supply UK EU US 3 BNC to BNC cable x 2 4 BNC Jack to Phono plug 5 BNC Plug to Phono socket 6 9 way D to Lemo link lead ...

Страница 13: ...s performed at the surface using the top side display Fitting the Probe module The Probe module consists of a nosecone an integral length of underwater coaxial cable and the probe itself It is attached by screwing the nosecone section on to the end of the Gauge body hand tight Do not use the nosecone Torque Bar to tighten the nosecone See page 44 There is an O ring seal A fitted to the nosecone an...

Страница 14: ...nection To maintain the integrity of the electrical operation and watertight seal it is essential that these precautions are observed Cable connection should only ever be made in dry ambient conditions at the surface Connections must never be made or broken underwater Both the male underwater cable Connector and the Blanking plug should have Silicone grease smeared on the pins before inserting int...

Страница 15: ...put is also protected against accidental reverse polarity connection There is no ON OFF switch The Gauge will operate continuously whilst power is connected There will be an initial delay of about 2 seconds and then the instrument will begin continuously transmitting thickness measurement data A Test Cable is supplied in the main Gauge Kit which can be used to verify the Gauge operation If you are...

Страница 16: ...are USB port on your computer Connection to the ROV Craft In this method the connection from the Gauge is taken to the ROV craft itself and is merged with the ROV s own cabling to connect to the surface See pages 64 and 65 Power for the Gauge can be taken from the ROV s own power supply if suitable It is essential that the data connections from the Gauge are maintained throughout as twisted pair I...

Страница 17: ...ap In ROV applications the water can be considered to be a coating Thus it is possible to measure steel thickness through a small water gap between the probe and the material under inspection As the Velocity of Sound for seawater is approximately 1500m s this equates to a maximum seawater gap of 2 25mm ...

Страница 18: ... application to read the serial data and process the thickness measurement data For more information on the Serial Data Format to enable use of your own software see page 53 Data Logging The CygLink software also provides the facility to Data Log the thickness measurements as they are taken and to generate a report document for the survey Video Overlay The optional TSR unit has a Video Overlay or ...

Страница 19: ...asure This method determines the velocity of sound for the material sample which will always be more accurate than using a general velocity value For calibration instructions using CygLink see Calibrating to a Known Thickness using CygLink on page 31 or with the TSR see Calibrating to a Known Thickness using a TSR on page 21 If there is no test sample available the Gauge can be calibrated by setti...

Страница 20: ...ording device Turning the Unit On 1 Press the red ON key 2 The Cygnus Logo screen appears 3 If not connected to a Gauge the display shows NO CONNECTION This is normal it just means no data has being received yet Changing the Displayed Units 1 Press the MENU key to display the MENU 2 Press the DOWN ARROW key to scroll down to UNITS the current units are displayed 3 Press the EDIT key to toggle betw...

Страница 21: ...U 3 The CALIBRATE menu option should be selected at the top 4 Press the EDIT key to adjust the measurement value to the known thickness of the sample being measured Press the OK key to save and exit 5 Repeat from step 1 to check the calibration is stable Display Hold Function The middle key HOLD can be used to freeze the display and hold the current thickness measurement 1 Press the HOLD key to fr...

Страница 22: ...through the TSR The TSR will automatically detect and adjust for PAL or NTSC video signals it will work with colour or monochrome images Positioning the On Screen Display OSD Because there is usually other information displayed on the video screen the TSR has the facility to move the thickness measurement display box anywhere on the screen using X Y coordinates The position selected will be stored...

Страница 23: ...and exit 6 Press EXIT again to exit the menu screen Testing the Link Before use on a job it is recommended to test the link between the Gauge and the TSR To do this simply power on both the TSR display and the gauge then measure the test block the TSR should display the correct test block thickness Troubleshooting Error Messages 1 NO CONNECTION The TSR has not received any valid data since power u...

Страница 24: ...ng of the units 4 Data Logging of thickness measurements into a Survey report It should be noted that although Cyglink supports A Scan the Cygnus MINI ROV Gauge does not Kit Contents The CygLink kit comprises the following items 1 USB RS485 RS422 Converter Cable 2 CygLink Software Installer on USB Flash Drive You will also need an Umbilical cable and connectors to connect the Cygnus MINI ROV Gauge...

Страница 25: ... instructions To install from a flash drive connect it to a free USB port on your computer Navigate to the flash drive in Windows Explorer and open the folder present in the root of the drive Run the application named setup exe to begin the installation process You will need to accept the End User Licence Agreement in order to complete the installation and a summary of its terms is provided at the...

Страница 26: ...ick the Manual Setup box and select the correct COM port number Finding your COM Port Number With the USB RS485 Converter plugged into your computer open Windows Device Manager to do this press the Windows key and the R key together then type devmgmt msc into the prompt followed by enter key In the Ports section look for the USB Serial Port entry Remember the COM number listed as this will need to...

Страница 27: ...n Device Manager Each version of Windows has a slightly different procedure for opening Device Manager The most direct route is to press and R keys together type devmgmt msc and press Enter Select the USB Serial Port device and right click to display its context menu Click Properties On the Properties form select the Port Settings tab then click the Advanced button ...

Страница 28: ...e the COM Port number Finish by clicking the OK button Running CygLink Application Once installed CygLink will place shortcuts in the start menu and on the desktop Click either to start up CygLink You are first asked to either Create New Survey Open Survey or Continue choose Continue to proceed without a Survey loaded ...

Страница 29: ...re to the Cygnus MINI ROV Gauge assuming the gauge is connected and turned on from the top menu click Gauge then Connect to Gauge then ROV Gauge Bottom Left of CygLink Main Screen with Connection to Gauge The Connection Status is shown in the status bar at the bottom left this should be green Also shown in the status bar are The Gauge type M4 ROV The Echo Mode Multiple Echo ...

Страница 30: ...settings click Gauge Measurement Settings You can change the Units and Velocity Measurement Settings Screen Velocity Table You can select the Velocity of Sound from a table of common materials In the Velocity tab of the Measurement Settings screen click the button to display the list for common materials Velocity List ...

Страница 31: ...splay 2 Click Gauge Calibrate With the probe still held on the material sample Calibration Menu 3 Select the value in the Thickness box and enter the known thickness of the sample being measured Press the OK to save and exit 4 Repeat from step 1 to check the calibration is stable CygLink Surveys and Data Logging CygLink has the facility to store logged thickness measurements in a single Survey fil...

Страница 32: ...gnus MINI ROV Operation Manual M4 CYGMINI TSR M ENG_Iss 1 Page 32 of 66 Right side of CygLink main screen with a Survey Group with 4 Measurements You can Save Open or create New Surveys from the File menu ...

Страница 33: ...Details To view and edit the survey Group details select the Survey Group from the top right list and double click to Edit You can mark the Group as complete by changing its Completed status Once marked as complete you won t be able to add any further measurements To create a new Group click the button in the toolbar at the top of the Group list the New Group screen is displayed Here you can set i...

Страница 34: ...easurements in the Survey grouped by each Survey Group From the File menu select Create Survey Report PDF You will be prompted for a filename for the report Once the export process is complete your report will automatically be displayed in your installed PDF viewer The export may take a few seconds depending on the number of logged measurements Exported PDF Report Extract M4 ROV ...

Страница 35: ...of measurements that can be added to each Group Create new Survey Group Record dialog Linear or Grid Data Logging When you use CygLink to data log measurements you can choose to create a Linear list of measurements or a two dimensional Grid of measurements To create a Grid simply edit the Record Type field in the Survey Group Details and set it to Grid you can then specify the direction the measur...

Страница 36: ...t Measurement Comments List You can add up to 8 short text comments which can then be used to append to a thickness measurement To set up your comments click File Measurement Comments Measurement Comments Screen Adding Comments or Notes to a Measurement You can add your own quick text Notes to any logged thickness measurement just select the measurement point in the list and right click to display...

Страница 37: ...eld An example Pre set Comments List CygLink Trouble Shooting Connection Problems USB Drivers If you are unable to get a connection the first thing to try is updating the USB drivers for the Serial USB converter Windows is constantly being updated and as a result drivers also need to be updated to keep track of changes The Serial to USB converter used for the Cygnus MINI ROV Gauge is manufactured ...

Страница 38: ...e between the Cygnus MINI ROV Gauge and the USB converter is damaged or has been repaired incorrectly Although there are only 2 data wires they must be connected the correct way around Double check the connections from the gauge s connector to the serial converter connection If you have the short serial to USB interface cable check the gauge can connect to CygLink using this cable if it works then...

Страница 39: ... the membrane regularly as it is important the membrane is changed as soon as it shows any signs of wear Probe Selection Apart from the physical limitation of the probe size the diameter of the probe face crystal and the frequency affects the probe performance Generally Large diameter probes produce more energy which gives better performance on heavily corroded or coated materials Higher Frequency...

Страница 40: ...new membrane into the end of the Knurled Ring ensuring it locates in the groove 4 Screw the Locking Ring back inside the Knurled Ring and tighten with the Locking Ring Key 5 Place a few drops of Membrane Couplant on to the probe face 6 Screw the Knurled Ring back onto the probe Use your thumb to squeeze the couplant from under the membrane as you tighten the Knurled Ring down 7 You should see the ...

Страница 41: ...rfaces are relatively rough 6 mm inch 5 MHz 1 0 50 mm 0 04 2 inch The higher frequency and narrower beam makes this probe ideal for measuring small bore tubing thin section plate and other areas where access is limited 13 mm inch 5 MHz 1 0 50 mm 0 04 2 inch Ideal for thin sections without heavy corrosion Lower frequency probes offer better penetration on heavy corrosion or coatings 1 To measure th...

Страница 42: ...onic signal through the material being measured To ensure the ultrasonic probe has the best chance of detecting the return echoes there are some basic rules that need to be considered when designing the probe holding tooling 1 The probe face must be presented flat perpendicular to the surface being measured 2 Apply gentle pressure to the probe while measuring to maintain contact with the surface ...

Страница 43: ... fit as shown in the diagram above where A is fitted into the O Ring groove in the nosecone housing B is to be fitted in the O Ring groove at the front of the instrument It is important to ensure that the O Rings are properly located There is no need to stretch or force the O Rings into their locations All parts are designed to ensure a good water tight fit Incorrect fitting will result in the ins...

Страница 44: ...ne after each submersion Removing the Nosecone The nosecone can be difficult to remove when the O rings have been compressed so a Tommy Bar is supplied with the kit to allow extra leverage to be applied to break the seal Fit the Tommy Bar into the hole in the nosecone then unscrew using the Tommy Bar as a lever Wrong Torque or Tommy Bar Nosecone Gauge Body ...

Страница 45: ...aling area may occur 2 Clean the O ring locations removing all grease and dirt 3 Pre lubricate the new O rings with Silicone grease 4 Gently fit the new O rings into position see page 43 Checking the O rings To ensure the gauge remains water tight these O rings must be checked each time you remove the battery pack or nosecone It is recommended to replace the O rings if in any doubt as to their con...

Страница 46: ...grease Do not use old or damaged O rings Never use the Gauge without any O rings fitted Spare O rings are included in the Kit and can be ordered from Cygnus Instruments see page 9 for contact details Things to look for when inspecting the O rings are Any flats or signs of wear Any signs of pinching or trapping Any sand or dirt in the Silicone grease Any cuts or cracks ...

Страница 47: ... otherwise impossible Beware that in extreme conditions or if the plate is of poor quality and contains many inclusions the ultrasound will be scattered to such an extent that measurement may not be possible Beware that the multiple echo technique will not work if the front and back surfaces of the material being measured are not close to parallel Also note that long narrow bars cannot be gauged a...

Страница 48: ...us 1 flashing bar but never any reading this means the Gauge is receiving unrelated echoes from more than one reflector On heavily corroded areas this is often a problem try and take measurements in adjacent areas of the same material Check the Gauge and Probe together on a test block if there is still no reading the Gauge may require servicing If Readings are Erratic or Unstable Check that the Pr...

Страница 49: ...ging the Membrane on Page 40 2 Is the Probe lead OK Check the probe lead is in good condition and is correctly attached to the Gauge See page 13 3 Is the material measurable at all Are the front and back faces of the material parallel Is the material too heavily corroded Is the material too thin for the Probe being used See page 41 It is often worth confirming that the Gauge is operating OK using ...

Страница 50: ...ken not to allow water into the instrument body whilst cleaning Do not use solvents for cleaning Do not use any abrasive cleaner Use of O Rings When reassembling before a submersion always replace both O Rings with new first ensuring that they are lubricated with Silicone grease To avoid the risk of a leak prevent accidental re use by destroying all used O Rings after each submersion Data link con...

Страница 51: ...rvice is available from Cygnus Instruments The Complete Kit should always be returned for Service or Repair including all Probes and Leads Cygnus Gauges are renowned for their reliability very often problems with getting measurements are simply due to the way the Gauge is being used See Troubleshooting on Page 48 However if you do need to return your Gauge for Repair please let us know the details...

Страница 52: ...easurement Range Measurement Ranges in Steel 2 MHz probe 3 mm to 250 mm 0 120 in to 10 00 in 3 MHz probe 2 mm to 150 mm 0 080 in to 6 000 in Accuracy 0 05 mm 0 002 High Resolution Mode and measurement 100 0 mm 0 1 mm 0 005 Low Resolution Mode or measurement 99 95 mm Resolution 0 05 mm 0 002 High Resolution Mode and measurement 100 0 mm 0 1 mm 0 005 Selectable Low Resolution Mode or measurement 99 ...

Страница 53: ...s you must re scale the received thickness value for the velocity of sound required For example when measuring carbon steel with a velocity of 5920 m s you will need to apply the following conversion factor True Thickness Received Thickness 5920 6400 Protocol 1 Unidirectional Gauge transmits only 2 Eight Data bits 1 Start bit 1 Stop bit No Parity 2400 baud 3 Four packets per second 4 Valid Reading...

Страница 54: ...tion 1 Remote always 0 No Reading 1 No Thickness Reading 0 Valid Thickness Reading Data bytes Arrangement The four data bytes are ASCII encoded decimal thickness value Data byte 0 is most significant Leading zeroes are replaced by ASCII Space hex 20 Decimal points are implied from the Status byte Units Resolution and Range bits Reading type Hi Range Lo Range Imperial Lo Resolution x x x x x x x x ...

Страница 55: ... Gauge returns all Readings in a 4 byte decimal string Readings which require 5 bytes e g 100 00 mm or 10 000 inch are auto ranged to the 4 most significant bytes Range bit for every Reading must be read from the Status byte Resolution The Gauge is factory set to Lo Resolution setting 0 1 mm or 0 005 inch but may be changed by the user to Hi Resolution setting 0 05 mm or 0 002 inch as required Uni...

Страница 56: ...velocity cl Material Velocity of Sound V Conversion Factor f m s in us Aluminium alloyed 6380 0 2512 1 078 Aluminium 2014 6320 0 2488 1 068 Aluminium 2024 T4 6370 0 2508 1 076 Aluminium 2117 T4 6500 0 2559 1 098 Brass CuZn40 4400 0 1732 0 743 Brass Naval 4330 0 1705 0 731 Brass CuZn30 4700 0 1850 0 794 Copper 4700 5000 0 1850 0 1969 0 794 0 845 Grey Cast Iron 4600 0 1811 0 777 Inconel 5700 0 2244 ...

Страница 57: ...ken on a material other than Steel it may be easier to leave the calibration set for Steel and merely convert the readings by multiplying by the Conversion Factor for the material being measured This method avoids unnecessary recalibration Example The Gauge is calibrated for Steel 5920 m s but the reading is being taken on Copper 4700 m s T t x VCOPPER VSTEEL t x 4700 5920 t x 0 794 thus T t x f w...

Страница 58: ... with Video On Screen Display for Cygnus MINI ROV Software Part No Description 001 8212 Cygnus CygLink v4 Topside Software on USB Flash Drive Underwater Probes with 1 Metre Lead All probes are fully assembled and include a spare membrane pack and knurled ring locking key Part No Description 001 8334 Probe 2 25MHz 13mm for MINI ROV 1m cable 003 9410 Probe 2 25MHz 19mm for Cygnus MINI ROV Lower freq...

Страница 59: ...e for use on surface temperatures up to 150 C Part No Description 001 3702 Pack of 20 Polyurethane Membranes for 6mm Probes 001 3701 Pack of 20 Polyurethane Membranes for 13mm Probes 001 3700 Pack of 20 Polyurethane Membranes for 19mm Probes 001 4873 Pack of 10 Teflon Membranes for 6mm Probes 001 4874 Pack of 10 Teflon Membranes for 13mm Probes 001 4875 Pack of 10 Teflon Membranes for 19mm Probes ...

Страница 60: ... 3705 Knurled Ring Assembly for 19mm Probes 001 2612 Membrane Key for 6mm Probes 001 2611 Membrane Key for 13mm Probes 001 2610 Membrane Key for 19mm Probes Cables and Leads Part No Description 001 0418 Impulse Connector 4 Way with Flying Lead 001 0432 Test Cable Impulse with DC Power for Mk3 4 ROV Gauges Electronic Bodies Only Part No Description 001 7190 4 Cygnus MINI ROV Mountable UTG Gauge Bod...

Страница 61: ...rspex supplied with material type and dimensional accuracy traceable certificate 001 8308 Isolated Data Converter RS422 to RS232 Model K3 003 0422 RS232 to USB Serial interface cable 001 3712 O Ring Pack for Cygnus MINI ROV Mountable Gauge Kit contents 20 x O ring type A and 20 x O Ring type B 001 4813 ROV Pelican Carry Case for Cygnus MINI ROV Gauge Kit ...

Страница 62: ...h high quality materials and components which can be recycled and reused It may contain hazardous substances that could impact health and the environment In order to avoid the dissemination of those substances in our environment and to diminish the pressure on natural resources we encourage you to dispose of this product correctly DO NOT dispose of this product with general household waste DO disp...

Страница 63: ...dependent Cable Connection Recommended cable connection for direct cabling from Cygnus MINI ROV Gauge to surface computer Cable termination for long cables it may help to fit a 120 Ω resistor in series with a 1nF capacitor between the TX and TX connections inside the 9 way D type plug See datasheets on the supplied USB Flash Drive for the K3 receiver and MAX483 line driver ...

Страница 64: ...Cygnus MINI ROV Operation Manual M4 CYGMINI TSR M ENG_Iss 1 Page 64 of 66 20 ROV Local Termination Connection Recommended cable connection from Cygnus MINI ROV Gauge to ROV craft ...

Страница 65: ... to computer Alternatively if you intend to convert the serial data sent from the Cygnus MINI ROV Gauge using your own electronics and or software the TX TX data pair may be connected directly to any RS 422 compatible receiving equipment K3 KSYSTEMS RS232 RS422 RS485 WWW KKSYSTEMS COM RS232 RS485 RS232 ISOLATED INTERFACE CONVERTER ...

Страница 66: ...al Table 30 PDF 34 Data Output 15 Disposal 62 Measuring Through Water 17 Nosecone Removing 44 O Rings Checking 45 Molykote 45 Replacing 44 Power Supply 15 Probes Knurled Ring 40 Locking Ring Key 40 Membrane Couplant 40 Polyurethane Membrane Membrane 39 Selection 39 Specifications 41 Problems 51 Pulse echo 8 Recycling 62 Repair 51 Rough surfaces 47 Serial Data Format 53 Service 51 Sound Velocities ...

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