The EPOCH LT is a basic, handheld digital flaw detector, 38 mm (1.5 in.) thick and packed in a 1 kg (2.35 lbs) vertical package gives fast display update rate at a minimum 60 Hz, automated transducer calibration, a numeric datalogger, and many other measurement features.
The new EPOCH LT is the lightest, thinnest flaw detector you've ever seen. This is a handheld digital flaw detector that is just 38 mm (1.5 in.) thick. Packed in a 1 kg (2.35 lbs) package the EPOCH LT gives you a fast display update rate at a minimum 60 Hz, automated transducer calibration, a numeric datalogger, and many other measurement features. The EPOCH LT is the perfect solution when you need to perform quick, basic flaw detection in difficult field conditions or demanding production environments.
The Heavy-Duty Lightweight
Although small in size, the EPOCH LToffers many of the performance features you'd normally expect to find in bulkier flaw detectors. In addition to its fast 60 Hz update rate, the EPOCH LT has a Display Freeze Mode that holds waveform soundpath data, Peak Memory that simultaneously displays live waveform and peak envelope of A-scan, RF display mode, selectable threshold positive/negative or minimum depth Alarm Modes, and Auto Transducer Calibration that calibrates for transducer zero offset and/or material velocity.
An on-board numeric datalogger is simple to use and can store up to 100 calibrations/2000 thickness measurements. An optional Expanded Memory feature that allows storage of 500 calibrations/10000 thickness measurements. The EPOCH LT datalogger is compatible with files from the other EPOCH 4 series instruments and the GageView™ Pro Interface program.
Extensive Documentation And Transfer Capabilities
The optional Windows®-based GageView™ Pro Interface program adds practical collection, editing, and review capabilities to the EPOCH LT. GageView Pro is a powerful tool that collects, manages, and formats stored inspection data.
GageView Pro database tracking allows setup of inspection plans with pre-loaded calibrations, IDs, and memos. Data can be printed or easily copied and pasted into word processing and spreadsheet documents for further reporting needs.
EPOCH LT, Microprocessor-Based
Ultrasonic Flaw Detector with numeric datalogger includes:
GageView™ Pro Interface Program
including USB cable (PN: GAGEVIEWPRO-KIT-USB)
*All specifications are subject to change without notice.
API 5UE - The API 5UE software option for the EPOCH series is intended to assist with performing inspections in accordance with the American Petroleum Institute's Recommended Practice 5UE. This practice was developed specifically for OCTG manufacturers to inspect and characterize inner-diameter (ID) cracking in newly fabricated pipe. The API 5UE code uses two crack sizing methods to characterize ID cracking: the Amplitude Comparison Technique (ACT) and the Amplitude-Distance Differential Technique (ADDT). The software aids in performing the ADDT method, which is based on the formula:
d i =Amax(T 2 -T 1 )k
API 5UE inspections are accomplished using the Peak Memory function on the EPOCH 4 flaw detectors to draw a peak envelope of the crack signal and quickly capture the Amax, T1 and T2 points using a single key press. Using this collected data from the peak envelope, the EPOCH flaw detector performs the necessary calculation using the formula above and displays the crack height in the upper right corner of the screen.
The ADDT inspection method can also be performed using the API 5UE software in a manual mode, allowing the operator to manually select the values for Amax, T1 and T2. All API 5UE data can be easily stored using the EPOCH 4 series datalogger, and the full inspection data can be downloaded to a PC using the EPOCH 4 series interface program, GageView Pro.
AWS - The AWS D1.1/D1.5 software option for the EPOCH series is intended to assist with performing inspections covered under the American Welding Society D1.1 and D1.5 Structural Welding Code for steel. This code provides inspectors with a method to classify discontinuities found in welds using ultrasonic inspection. This code uses the following formula to develop an indication rating for a reflector found during an inspection:
An AWS D1.1 inspector must take the Indication Rating (D) that is calculated based on A, B, and C to an Ultrasonic Acceptance - Rejection Criteria table produced by the AWS in order to classify the severity of the discontinuity that has been located.
ADT - The Advanced DAC/TVG (ADT) software option is intended to significantly enhance the functionality of the standard DAC/TVG options already available on the EPOCH series flaw detectors, allowing users to customize inspections to their unique application requirements. The ADT feature incorporates the high-quality capabilities that adhere to ASME, ASME-3 and JIS sizing codes of standard DAC/TVG options with direct control of gain, range and zero offset, as well as reference and transfer correction. In addition, the ADT option provides new features such as 20%-80% DAC curves, customizable DAC curves, and a user-defined TVG table to meet advanced and unique inspection needs. ADT also allows the user to toggle between DAC and TVG views in many of its functions, allowing the operator the freedom to utilize both techniques during a single inspection.
Advanced DAC Options ADT's enhanced Distance Amplitude Correction functionalities allow more user control over the information acquired and displayed while sizing flaws compared to known reflector amplitude returns. A DAC curve is used to plot amplitude variations of signals from reflectors of the same size, but at different distances from the surface. A single DAC curve is used to plot the peak amplitude of each reflector at different depths within a material to compare with peak amplitude returns from unknown flaws. In the ASME-3 criteria, three DAC curves are plotted: one at peak amplitude, one 6dB below this point (indicating a reflector 50% the size of the reference), and one 14dB below the peak amplitude point (indicating a reflector that is 20% the size of the reference). Advanced DAC takes this functionality many steps further. The operator now has the option to customize up to three DAC curves at user-defined levels between +6dB and -24dB from the primary DAC curve. Additionally, since DAC curve inspections are not valid in most applications when a reflector is below 20% of full screen height, the ADT software allows a new dynamic 20%-80% function, which automatically adjusts the gain of reference signals below 20% up to 80% during setup. This allows a great range for inspections while minimizing the necessary manual gain adjustment. Should gain adjustment be necessary, the Advanced DAC and TVG functions now have a reference correction feature that provides the operator with a digital amplitude measurement of reflectors that is directly compared to the DAC curve level, even with significant gain adjustment during the measurement.
Advanced TVG Options In addition to providing all the options from Advanced DAC in a TVG display for seamless integration of the two sizing techniques, the ADT software now offers a customizable TVG Table option for direct access to TVG point adjustment. This new feature allows fine manual adjustment of any captured TVG points, both for gain and position, as well as manual entry of new TVG points. The TVG Table is also completely compatible with the 1kHz High PRF option on the EPOCH 4 and EPOCH 4 PLUS instruments, as well as the Interface Gate option on those instruments, allowing for specialized fast scanning and on-line inspections previously out of reach of the EPOCH 4 series instruments.
Onboard DGS/AVG - The Onboard DGS/AVG option is a replacement for the old DGS/AVG option that has been available in the EPOCH 4 and 4 PLUS , which required a PC Interface Program for DGS/AVG setups. This new option allows complete DGS/AVG setups to be performed on the instrument.
The DGS/AVG method allows the operator to size defects based upon a calculated DGS/AVG curve for a given transducer, material, and reflector size, and has been designed to meet the requirements of EN 583-2:2001. This method requires that the operator only has one reference reflector in order to create a DGS curve for flaw sizing. This is much different than the DAC or TVG method which requires that the operator have representative defects at various depths within a part in order to create a curve for flaw sizing.
To allow the operator to setup DGS/AVG curves on the instrument very quickly, Olympus has developed a transducer library that is stored in the instrument's memory. All of the required data for building DGS/AVG curves is stored in the instrument's memory for each transducer in the library. The onboard DGS/AVG option provides the operator with rapid setup times and easy flaw size evaluation.
After activating the DGS/AVG software option and selecting the appropriate transducer from the probe library, the operator is walked through a series of instrument setups to display the DGS/AVG curve that correctly corresponds to the operator's particular inspection. These steps include defining a reference reflector, entering adjustment parameters for the critical flaw size of the inspection and entering parameters to compensate for material attenuation of the test piece and calibration block.
Spotweld Assistant (SWA) - The Spotweld Assistant software option is only available with the EPOCH 4 PLUS flaw detector, and is intended to provide automated weld quality analysis using a combination of the industry-proven Spotweld Overlay functionality with an advanced quality analysis algorithm. This software feature greatly enhances the EPOCH series' capability to inspect and characterize spotwelds with improved efficiency and accuracy.
Ultrasonic inspection of spotwelds involves the analysis of what is known as the "ring-down" of sound energy within the weld nugget. Unlike many direct-measurement techniques, spotweld inspection looks at the characteristics of the multiple echoes returned from sound ringing within the weld nugget to determine the quality of the weld. Echo spacing, sound attenuation, and intermediate echo detection are some of the indicators of weld quality analyzed by trained inspectors. Ultrasonic spotweld inspection is completely based on comparison between known "Good" and "Unweld" conditions with unknown welds, and requires a highly trained operator to perform a comprehensive inspection.
The Spotweld Assistant is not intended to remove the necessity of a trained operator; instead, it is meant to enhance the ability of a trained operator to judge welds more efficiently. The operator begins by storing both a "Good" and "Unweld" reference condition into the EPOCH 4 PLUS to calibrate these control situations. The software then uses default comparative algorithms to rate unknown welds based on these stored conditions. If the trained operator disagrees with the software's recommended weld rating, the operator can override this rating manually.
GageView Pro Inspection Plan
Interface Gate - The Interface Gate option is designed to graphically compensate for the change in a water path distance or other delay between the test material and transducer. When the option is activated, a third gate (Interface Gate) is visible on the EPOCH's display. You can position this Interface Gate in the area where you expect to detect the interface echo. The interface echo is a result of the sound energy reflection at the interface between
the water path and the front surface of the test material. The Interface Gate maintains the interface echo on the left hand side of the EPOCH screen, regardless of the water path distance, thereby maintaining a precise "acoustic" zero from which the instrument makes digital measurements. The instrument's flaw gates (Gate 1 and 2) automatically track the location of the Interface Gate. The Interface Gate can be used in standard measurement mode or in
High Pulse Repetition Frequency
High Pulse Repetition Frequency (PRF) - In many "on-line" immersion applications, the inspection pieces are passed by the transducer at a fast pace compared to normal, manual scanning. If proper care is not taken, this can result in an effect known as "interleaving". This occurs when a pulse is transmitted into the test material, but the transducer moves prior to the return signal, and it can result in the loss of important data. To compensate for this effect, the High PRF option is used to hold the rate at which a pulse is transmitted into the test material at a high value (1,000 Hz). This is commonly used in conjunction with the Interface Gate option for "on-line" immersion inspection of parts moving quickly by a fixed transducer.
Low Pulse Repetition Frequency
Low Pulse Repetition Frequency (PRF) - The Low Pulse Repetition Frequency option is available on all of the EPOCH series instruments, and is designed to hold the pulse repetition frequency (PRF) of the instrument to a fixed setting of 30 Hz. This option is commonly used in inspections that deal with materials that have very long sound paths, and is intended to avoid a phenomenon known as "wrap-around noise". When inspecting a piece with a long sound path at normal "Auto" PRF, there is a point when the time the sound takes to make a full round-trip from pulse to receive is longer than the time between pulses. If a test setup produces multiple echoes, then the issue is the length of time required for the last multiple echo to arrive at the receiver. Normally, the instrument builds a waveform response by pairing a certain pulse with its return signal and analyzing the characteristics of the return signal. However, in this situation, the received signal does not correspond to its initial pulse (according to the instrument's timing algorithm). The overall affect is the potential for random noise and echoes on the A-Scan display. The Low PRF software feature slows the pulsing of the unit and allows for a certain pulse to be correctly paired with its return signal.
Floating Gate - The Floating Gate software allows the operator to track and make measurements from A-Scan echoes at either the -6dB or -12dB point. After activation and setup, the gate "floats" at either of these points and tracks changes in the amplitude of a captured signal. This feature is intended to take more consistent, precise readings, especially in Edge Detect mode, by always taking measurements from the same relative amplitude of an echo. The feature also helps to maintain constant measurements in scanning applications where quality of transducer coupling may vary. The Floating Gate software is included with the B-Scan software, and is commonly used in conjunction with Edge Detect mode and B-Scan to maintain the accurate acquisition of measurements from corroded pipe and other materials. Floating Gate can also be used with the Interface Gate to track amplitude changes in the interface echo.
Curved Surface Correction
Curved Surface Correction - The Curved Surface Correction software is intended to adjust digital measurements from a curved inspection surface during angle beam inspection, to compensate for curvature effects on sound path length. The algorithms built into the EPOCH instruments to calculate sound path (V-path) distance, surface (skip) distance, and depth of a reflector when performing angle beam inspection are written for flat surfaces, such as welded plates. The measurement calculations are different in curved surfaces, such as pipes and cylinders, due to the more complex geometry of the part. Therefore, a separate algorithm has been written, the Curved Surface Correction, that requires the operator to input the outer diameter of the test piece and then calculates the correct V-path, skip distance and depth of a reflector. All other calibration settings, including verification of refracted angle and part thickness, must be entered correctly for accurate measurements.
Spotweld Overlay - The Spotweld Overlay software option provides stored templates for comparison of unknown spotweld conditions to known Good, Stick, Undersized, and other known weld conditions. Upon activation, the operator uses the five soft keys (F1-F5) on the EPOCH to store templates of known weld conditions. These templates can then be recalled to the screen over an unknown weld condition under interrogation (in live A-Scan or Freeze mode) for comparison purposes. Although this option was specifically designed for Spotweld inspection, its template and comparison capabilities can be used in a variety of applications.
Autofreeze - The Autofreeze software option allows the operator to automatically freeze the live A-Scan when a gate alarm is triggered. This function is typically used in scanning applications or applications with signals that are difficult to obtain and/or maintain because of coupling or orientation issues. The operator activates a gate alarm and sets the gate parameters to capture only echoes of interest, and any echo that breaks the gate and triggers the alarm automatically activates the screen freeze function. This allows the operator to thoroughly inspection signals that may be difficult to catch or maintain in a live screen.
Backwall Attenuator - The Backwall Echo Attenuator software option is only available in the EPOCH 4 PLUS, and is designed to independently adjust the gain in a screen range region defined by the Gate 2 start point and beyond. The Backwall Echo Attenuator option is commonly used with two specific forms of inspections, both dealing with very small defects. The first is an inspection where potential defects may not be oriented parallel to the direction of sound from the transducer. In this situation, sound will reflect from the defect but not return to the transducer due to the orientation of the reflector. Therefore, such defects are detected by monitoring for backwall signal loss or attenuation. This backwall amplitude change may be missed entirely if the backwall signal is saturated. The Backwall Echo Attenuator option allows the operator to monitor the backwall at a lower gain setting for any signal loss, while still scanning the remainder of the test piece at a high gain level for small defects. The second common inspection for the Backwall Attenuator is in porosity inspection. Because porosity tends to scatter sound instead of return a clear echo, backwall amplitude is sometimes the only way to positively differentiate porosity from material grain structure. The Backwall Echo Attenuator is again used to bring the entire backwall signal on screen to be closely monitored by the operator.
Wave Analysis - The Wave Analysis software option allows the operator to make precise point-to-point measurements from any two points along a waveform. This option activates to indexing arrows that trace the length of the visible waveform in the A-Scan view. Typically, the operator will capture a single echo waveform using the instrument gate and use the zoom function to view the waveform close up. The Wave Analysis software then allows the operator to trace
the entire waveform with two arrows and take a measurement between these two arrows. A common application for the Wave Analysis software is the measurement of oxide scale on the opposite surface of a pipe or tube. The backwall echo is captured and zoomed using the instrument gate, and the Wave Analysis arrows are used to measure the distance between the peaks representing the inner and outer surfaces of the oxide layer, as seen below.
Echo to Echo
Echo to Echo - The Echo-to-Echo software option allows the user to make a digital measurement between two echoes captured in Gate 1 and Gate 2 on the instrument. This common measurement technique is used to increase the precision of thickness readings by measuring between multiple echoes of a single thickness inspection, eliminating any couplant layer or surface condition discrepancies. This technique is also used to get a clear measurement from a near-surface echo that is obscured by the ringing of the main bang in its first reflection(s).
Narrowband Filters - Narrowband Filters allow the operator to variably tune out unwanted or unnecessary ultrasonic frequencies being received from the test piece into the EPOCH. This filtering can significantly better the signal-to-noise ratio of the A-Scan, particularly in non-homogenous or scattering materials. The Narrowband Filters have preset ranges to encompass commonly used transducer frequencies, but with the Advance User Filter setting from the EPOCH settings menu, the Filters can be tuned to custom low- and high-pass settings for optimization of the option's capability.
Square Wave Pulser
Square Wave Pulser - The Square Wave Pulser is a powerful tool to improve penetration and response of transducers, particularly with low frequency probes and in highly attenuating materials. Unlike the standard, negative spike pulser of most UT inspection units, the tunable square wave pulser matches the EPOCH's excitation pulse duration to the frequency of a particular transducer, allowing the transducer to ring closer to its natural resonance and increase the amplitude of the signal transmitting into the test material from the transducer. This is especially useful with lower frequency transducers, as the natural resonant period of lower frequency transducers is longer than that of higher frequency tranducers and a traditional spike pulse does not obtain optimal results at these longer resonance frequencies.
Extended Range - The Extended Range option increases the standard measurement range of the EPOCH LT and EPOCH 4B from 0.16 inches - 200 inches (4mm - 5,000mm) to the extended range of 0.038 inches - 400 inches (1mm - 10,000mm).
Expanded Memory - The Expanded Memory option increase the memory capacity of the EPOCH LT, EPOCH 4B and EPOCH 4 to allow the storage of more waveforms/calibrations and/or thickness readings. The memory is expanded according to the table below:
The GageView and GageView Pro Interface Programs are Windows-based applications that collect, create, manage, and print data from Olympus thickness gages and flaw detectors.
GageView is compatible with gage models 35DL, 35DLHP, and MG2-DL. It provides the following capabilities:
GageView Pro is compatible with flaw detector models Epoch 4, Epoch 4B, Epoch LT, Epoch 4 PLUS, and Epoch XT, as well as the gage models listed above. When used with flaw detectors, GageView Pro provides the following capabilities: