- since 1996 -
|NDT.net Issue - 2009-03 - NEWS |
Superior Systems and Service for Welded Steel Tube Mill in Western Europe
Both systems include 5 transducers in total. One longitudinal transducer is used to detect the wall thickness and lamination. There are four shear wave transducers, two on either side of the weld line (two are sensitive to ID defects and two for OD defects), these four are used to detect longitudinal defects.
For these systems, five channels are provided. Two are for the longitudinal transducer and four for the shear wave transducers. A laser tracking system is also included to ensure correct positioning of the Ultrasonic transducers with respect to the weld line. The Multi Screen allows multiple channels to be viewed simultaneously in Strip Chart or A Scan mode. These systems are designed for in-line inspection of the weldzone, thickness measurement, and to detect ID/OD defects including lamination and longitudinal flaws. One system includes two lines, the first being dedicated to 91mm diameter tubing. This system is capable of handling wall thickness from 3-5mm and can reach speeds of 60m/min. The second line inspects 172mm diameter tubing with wall thickness between 3.5-8mm and maximum speeds of 60m/min. Both systems are designed to withstand temperatures as high as 80°c.
Western Europe Receives Off-line UT System 50 mm Echomac® UT Rotary
For this system, the 50mm UT has four transducers - two for longitudinal and two for transverse inspections. There are four channels that are also divided for longitudinal and transverse requirements.
The specifications for this system include 6-33 meter cut-lengths, OD between 15-50mm, wall thickness of 0.70-3mm, and a speed up to 30m/min. This is a full body system built to detect longitudinal and transverse discontinuities along with measuring wall thickness. The test is done off-line and tubes are sorted into good or defective based on customer requirements.
MAC's Largest System in Company History
The UT portion of this system includes the Echomac® FD-4 instrumentation and is MAC's first 220 mm UT rotary. The system is designed for the on-line testing of tubes (2.5" to 8" in diameter, with wall thickness from 4mm to 25mm) after heat treatment & straightening. This configuration will allow testing for internal, OD and ID flaws and is also capable of detecting oblique defects. The 220mm UT rotary stainless steel machined forging which is at the heart of the system, weighs 900 lbs. To maintain continuous water coupling for transmission of the UT signals, it must rotate at very high speeds in the neighborhood of 900 rpm.
The flux leakage portion of this system covers a combination of Rotary Transverse and Rotary Longitudinal Flux Leakage test system for detecting longitudinal and transverse notches on the OD or ID of heavy walled Tubes. The difference in concept between the rotary longitudinal station and the transverse station is that in the longitudinal station the rotation of the probes around the material provides the circumferential motion necessary to allow for detection of leakage flux as the sensors pass over a longitudinal defect. In the rotary transverse station the rotary motion is simply used to continually reposition a bank of transverse detectors around the circumference of the tube, thus providing 100% coverage.
50MM UT Rotary Includes New Features
Introduction of a different type of rotary bearing allows for field replacement of bearings. Instead of one preloaded bearing that usually required a return to the Mount Vernon factory for bearing replacement, the rotary now has two "deep groove" bearings that can be easily accessed and changed without any requirement for high pressure loading. An optional, easily attached bridge unit is available to support the test block during removal of the two rotary bearings which are now easily accessible from the outside of the transducer housing.
A new oiler system that constantly supplies fresh oil to the bearings will extend their life as well as permit increased rotary speeds. Other features include earlier improvements such as the seal-less design, and mounting of the Pulser/Receiver electronics on the rotary head. All these improvements are now being incorporated into MAC's UT rotaries (both metric and English). A 50 mm rotary is now installed in MAC's Boardman Ohio plant where it has already been used for an important demonstration for customers.
Ultrasonic and Eddy Current Multitest System installed in the United States
The Echomac® uses one longitudinal and two shearwave transducers and the electronics include three channels respectively. The Multimac® in this application is a single channel unit with a standard coil platform for non magnetic material. Additional components include dual pinch stands, a water recirculation system, and automatic markers. This system is mounted on a welded test bench with learn controls to automatically adjust the timing based on the initial test piece.
First Ultrasonic Test System to South Korea
With its current 120,000 tons of production a year, Jeen Yang Steel plans to double its capacity in the near future. The MAC UT 500 unit is capable of inspecting material from 23mm up to 127mm O.D. Testing speed ranges from 15 FPM to 200 FPM depending on testing specifications (notch length) and material parameters while meeting the full specifications. Up to seven separate flaw or dimensional transducers may be used simultaneously.
The UT 500 rotary mechanism spins the transducers and water couplant at relatively high speeds about the test material as it is fed through. This mechanism contains the transducers in holders that facilitate fast setup for different size materials. All components of the rotary mechanism, which come in contact with water, are constructed of acid resistant stainless steel. The rotary is capable of speeds up to 1800 rpm. To ensure minimum maintenance requirements, Echomac® rotaries have been designed as seal-less systems.
The water system is comprised of a chiller for maintaining couplant temperature within an acceptable range, filters for removing contaminants and pumps, and reservoirs for moving the water through the system. These systems are designed to handle the large volume of water required to maintain proper coupling in the rotary and to minimize use and disposal issues.
The UT 500 comes equipped with the FD4 electronics which operate with Echohunter® software in a Windows® environment. This software integrates a UT setup parameter panel, multi-channel viewing, tracking and chart recording, all into a single program for ease of use. Also included is an Automatic Test Bench with 4 triple pinches.
Large UT System Installed in Southwestern Europe
The 7 channel Echomac® FD-4 coupled to a UT300 rotary with an automatic bearing lubrication system, utilizing 4 channels of shear wave for defect detection and three channels in compression for delamination detection or geometry analysis, was supplied by the MAC Mt. Vernon plant.
Magnetic Analysis Nordic (MAN), in Ostersund, Sweden, supplied an inlet conveyor designed for the soft handling of tubes via a custom built feed mechanism, an outlet conveyor, and an automatic triple bench system. The UT rotary is mounted on a linear bearing slide table, and contains an air knife, marker system, and tube oiler. The bench includes spaces allocated for a future eddy current test. The "Conductor" system control operates all functions of the line utilizing a computer to set up for changes in diameter, end suppression, handling and sorting, plus data acquisition and network accessibility. Remote viewing capability is also provided.