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Complete ultrasonic immersion system under microprocessor control
Complete ultrasonic immersion system under microprocessor control
Full circumference radiograph with only one low energy exposure Significant cost savings and improvements in productivity are claimed for a new butt weld inspection technique developed by NEI Power Engineering Ltd in conjunction with the Central Electricity Generating Board and British Nuclear Fuels Ltd. The gamma ray isotope projection system (GRIPS) allows full 360 degree examination of butt welds with low energy isotopes (Yb-169 or Th-170) in a panoramic arrangement, the source being located inside the tube on its axis with the film positioned around the outside diameter. The source can be positioned on the tube centre line at a distance of up to 12 metres from its open end. The savings arise because the technique requires only one exposure for complete weld coverage compared with up to six shots for conventional double-wall single-image X-radiography. The GRIPS package is based on an automatic Isotopen-Technik remote control drive unit incorporating digital indication of source position and electronically controlled pre-set exposure delay and exposure time settings. A low friction flexible guide tube connected to the drive unit guides the isotope to the weld location, where its axial and radial position is accurately fixed by a pneumatically expanded centralizing head attached to the free end of the guide tube. A low activity source (Co-57) in the nose of the centralizing head and an external positioning unit incorporating a scintillation probe and meter are used to position the centralizing head/isotope accurately in relation to the weld centre line - - to within 5% of the tube bore diameter. This allows the system to be used with both austenitic and ferritic materials. The external positioning head also provides radiation shielding during exposure.
NDT INTERNATIONAL. JUNE 1982
For ease of transport the complete equipment package is mounted on a trolley. The system modules can be removed from the trolley for applications where access to the inspection area is limited. The range of equipment covers tube bore diameters from 18 mm to 110 mm, but this is currently being extended to 200 ram. Within these size ranges the flexible guide tube has been designed to negotiate tight bends in combination with straight, vertical and horizontal runs. Where large diameter thick-walled pipes are to be inspected the system can be used with Iridium 192 sources to optimize exposure times.
NEI Weldcontrol, Industrial Technology Unit, PO Box 13, Saltmeadows Road, Gateshead, Tyne and Wear NE8 1YZ, UK or Testrade Ltd, Stone Close, Horton Road, West Drayton, Middlesex UB7 8JU, UK
Microcomputers can provide sophisticated power and flexibility in the design of ultrasonic NDT systems, and these qualities are demonstrated in the US-510 lab scanner from Automation Industries Inc. The US-510 system includes a tank, water filtration/recirculation system and a scanning/recording assembly. Operational sophistication centres on a high-speed, multi-axis digital controller - - Microcomputer Intelligent Digital Ultrasonic System, MIDUS - - designed for a variety of applications and configurations. The immersion tank is 812 mm wide × 914 mm long × 457 mm deep and provides a maximum scanning area of 558 mm × 610 mm. A same-size, x-y C-scan recording is made on a mechanically linked platen. Accuracy and repeatability are assured by mounting both the longitudinally positioned bridge and the transversely positioned carriage on 25 mm diameter stainless steel ballbushing shafts. The longitudinal drive is rack and pinion and the carriage drive is ball screw. ServoStep drives are used for the high speed axes. These provide the scan axes with the torque, acceleration and speed of a DC motor combined with the precision and incre-
Automation Industries' microcomputer based ultrasonic immersion system - - t h e US-510
153
mental resolution of a stepper motor. Other axes are stepper motor driven. All axes are geared for a resolution of 0.025 mm per pulse. The MIDUS control system utilizes a distributed processor technique whereby dedicated microcomputers control specific functions. The system control board governs the activities of the scanner by directing each of the dedicated modules in response to operator inputs. The whole system, is designed around an Intel IEEE 796 Multibus. The MIDUS contains all the functions and controls required to automatically and manually position all the axes. Simultaneous multi-axis moves of all high speed axes may be made to any position within the system limits. The position of all axes are displayed at all times and updated every half second. This allows scan plans to be easily entered or altered. Automatic sequences may be interrupted for manual adjustments, defect evaluation or program correction and then automatically continued from the interrupt point. Other standard software features include automatic initialization, local storage of 40 scan plans, operator set park position, absolute work limits and a 'stop on defect' feature.
The Sontec AE corona dischargeand gas leak detector from FosterTransformersweighs only 2.5 kg and can be carried in a briefcase.
Two AE leak detectors: one from Foster...
Foster Transformers Limited has announced a new multipurpose AE test system designed for locating areas of corona discharge from power distribution lines or electrical equipment, and leaks from air or gas pressurized installations. Called Sontec, the equipment includes a battery-powered control unit containing a meter and loudspeaker, ultrasonic transducer, directional pick-up horn, sound concentrator and a headphone set. The total weight of the equipment is just 2.5 kg. A pinhole sight improves detection by helping to aim the pick-up horn
and focus the sound beam. With the horn alone a fault can be detected to within a 30 cm diameter circle at a distance of 10 m. The sound concentrator is used for close detection and for pinpointing small leaks to within 1 cm of the fault. For example, a gas leak from a 0.05 mm diameter puncture can be located at a distance of 1.5 m with a pressure system of only 0.7 kg/cm 2 (10 Ibf/in2). The equipment responds to sound signals in the 35-45 kHz bandwidth and can therefore be used in a noisy environment without loss of performance. Kate Grenshaw, Foster Transformers Ltd, Archcliffe Road, Dover, Kent CT17 9EN, UK ....
and another from Froude
Location of small leaks in water and oil systems is also said to be easy with a new detector from Froude Engineering Ltd. This equipment responds to the ultrasonic emission of escaping air to pinpoint extremely small leaks which might otherwise remain undetected. The detector employs a crystal transducer sensitive in the range of 36-44 kHz. When placed in the path of pressure waves caused by low pressure air escaping into the atmosphere, the transducer produces an electrical signal. Max-
A large variety of mechanical and software accessories are available: chain scan - - linking of any stored scan plans; a teach index; mini-scan - - automatic detailed scanning about a flaw indication; constant surface speed during turntable inspection; automatic normalization on the test piece surface; permanent scan storage on cassettes; slope control; digital and analogue turntables; and polar recorders. Software development is still continuing as part of the Automation Industries development programme, and by Spring 1983 the company hopes to have a profile capability as standard. This will allow the high speed examination of complex shapes such as propellor blades with the probe remaining normal to the surface at scanning speeds of up to 20 inches per second. Automation Industries Inc, Sperry Products Division, 20327 Nordhoff Street, Chatsworth, CA 91311, USA. SI (Systems + Instrumentation) Ltd 31 Bridge St, Pershore, Worcs, UK.
154
These three plastic containers were produced on the same machine under different moulding conditions. The fringe pattern of the moulding on the left, which has cracked, indicates an incorrect machine setting. The containers are being examined through a Sharpies strain viewing instrument which in addition to its use in optimizing moulding conditions is also applicable to the final inspection of mass-produced components. The standard instrument has a 230 m m square viewing field and consists of a light source white light or white monochromatic versions are available - an analyser and a polarizing element, all contained in a sheet steel casing. Sharpies Photomechanics Ltd, Europa House, Unit 468 Walton Summit Centre, Bamber Bridge, Preston PR5 8AX, UK
NDT INTERNATIONAL . JUNE 1982
Full circumference radiograph with only one low energy exposure Significant cost savings and improvements in productivity are claimed for a new butt weld inspection technique developed by NEI Power Engineering Ltd in conjunction with the Central Electricity Generating Board and British Nuclear Fuels Ltd. The gamma ray isotope projection system (GRIPS) allows full 360 degree examination of butt welds with low energy isotopes (Yb-169 or Th-170) in a panoramic arrangement, the source being located inside the tube on its axis with the film positioned around the outside diameter. The source can be positioned on the tube centre line at a distance of up to 12 metres from its open end. The savings arise because the technique requires only one exposure for complete weld coverage compared with up to six shots for conventional double-wall single-image X-radiography. The GRIPS package is based on an automatic Isotopen-Technik remote control drive unit incorporating digital indication of source position and electronically controlled pre-set exposure delay and exposure time settings. A low friction flexible guide tube connected to the drive unit guides the isotope to the weld location, where its axial and radial position is accurately fixed by a pneumatically expanded centralizing head attached to the free end of the guide tube. A low activity source (Co-57) in the nose of the centralizing head and an external positioning unit incorporating a scintillation probe and meter are used to position the centralizing head/isotope accurately in relation to the weld centre line - - to within 5% of the tube bore diameter. This allows the system to be used with both austenitic and ferritic materials. The external positioning head also provides radiation shielding during exposure.
NDT INTERNATIONAL. JUNE 1982
For ease of transport the complete equipment package is mounted on a trolley. The system modules can be removed from the trolley for applications where access to the inspection area is limited. The range of equipment covers tube bore diameters from 18 mm to 110 mm, but this is currently being extended to 200 ram. Within these size ranges the flexible guide tube has been designed to negotiate tight bends in combination with straight, vertical and horizontal runs. Where large diameter thick-walled pipes are to be inspected the system can be used with Iridium 192 sources to optimize exposure times.
NEI Weldcontrol, Industrial Technology Unit, PO Box 13, Saltmeadows Road, Gateshead, Tyne and Wear NE8 1YZ, UK or Testrade Ltd, Stone Close, Horton Road, West Drayton, Middlesex UB7 8JU, UK
Microcomputers can provide sophisticated power and flexibility in the design of ultrasonic NDT systems, and these qualities are demonstrated in the US-510 lab scanner from Automation Industries Inc. The US-510 system includes a tank, water filtration/recirculation system and a scanning/recording assembly. Operational sophistication centres on a high-speed, multi-axis digital controller - - Microcomputer Intelligent Digital Ultrasonic System, MIDUS - - designed for a variety of applications and configurations. The immersion tank is 812 mm wide × 914 mm long × 457 mm deep and provides a maximum scanning area of 558 mm × 610 mm. A same-size, x-y C-scan recording is made on a mechanically linked platen. Accuracy and repeatability are assured by mounting both the longitudinally positioned bridge and the transversely positioned carriage on 25 mm diameter stainless steel ballbushing shafts. The longitudinal drive is rack and pinion and the carriage drive is ball screw. ServoStep drives are used for the high speed axes. These provide the scan axes with the torque, acceleration and speed of a DC motor combined with the precision and incre-
Automation Industries' microcomputer based ultrasonic immersion system - - t h e US-510
153
mental resolution of a stepper motor. Other axes are stepper motor driven. All axes are geared for a resolution of 0.025 mm per pulse. The MIDUS control system utilizes a distributed processor technique whereby dedicated microcomputers control specific functions. The system control board governs the activities of the scanner by directing each of the dedicated modules in response to operator inputs. The whole system, is designed around an Intel IEEE 796 Multibus. The MIDUS contains all the functions and controls required to automatically and manually position all the axes. Simultaneous multi-axis moves of all high speed axes may be made to any position within the system limits. The position of all axes are displayed at all times and updated every half second. This allows scan plans to be easily entered or altered. Automatic sequences may be interrupted for manual adjustments, defect evaluation or program correction and then automatically continued from the interrupt point. Other standard software features include automatic initialization, local storage of 40 scan plans, operator set park position, absolute work limits and a 'stop on defect' feature.
The Sontec AE corona dischargeand gas leak detector from FosterTransformersweighs only 2.5 kg and can be carried in a briefcase.
Two AE leak detectors: one from Foster...
Foster Transformers Limited has announced a new multipurpose AE test system designed for locating areas of corona discharge from power distribution lines or electrical equipment, and leaks from air or gas pressurized installations. Called Sontec, the equipment includes a battery-powered control unit containing a meter and loudspeaker, ultrasonic transducer, directional pick-up horn, sound concentrator and a headphone set. The total weight of the equipment is just 2.5 kg. A pinhole sight improves detection by helping to aim the pick-up horn
and focus the sound beam. With the horn alone a fault can be detected to within a 30 cm diameter circle at a distance of 10 m. The sound concentrator is used for close detection and for pinpointing small leaks to within 1 cm of the fault. For example, a gas leak from a 0.05 mm diameter puncture can be located at a distance of 1.5 m with a pressure system of only 0.7 kg/cm 2 (10 Ibf/in2). The equipment responds to sound signals in the 35-45 kHz bandwidth and can therefore be used in a noisy environment without loss of performance. Kate Grenshaw, Foster Transformers Ltd, Archcliffe Road, Dover, Kent CT17 9EN, UK ....
and another from Froude
Location of small leaks in water and oil systems is also said to be easy with a new detector from Froude Engineering Ltd. This equipment responds to the ultrasonic emission of escaping air to pinpoint extremely small leaks which might otherwise remain undetected. The detector employs a crystal transducer sensitive in the range of 36-44 kHz. When placed in the path of pressure waves caused by low pressure air escaping into the atmosphere, the transducer produces an electrical signal. Max-
A large variety of mechanical and software accessories are available: chain scan - - linking of any stored scan plans; a teach index; mini-scan - - automatic detailed scanning about a flaw indication; constant surface speed during turntable inspection; automatic normalization on the test piece surface; permanent scan storage on cassettes; slope control; digital and analogue turntables; and polar recorders. Software development is still continuing as part of the Automation Industries development programme, and by Spring 1983 the company hopes to have a profile capability as standard. This will allow the high speed examination of complex shapes such as propellor blades with the probe remaining normal to the surface at scanning speeds of up to 20 inches per second. Automation Industries Inc, Sperry Products Division, 20327 Nordhoff Street, Chatsworth, CA 91311, USA. SI (Systems + Instrumentation) Ltd 31 Bridge St, Pershore, Worcs, UK.
154
These three plastic containers were produced on the same machine under different moulding conditions. The fringe pattern of the moulding on the left, which has cracked, indicates an incorrect machine setting. The containers are being examined through a Sharpies strain viewing instrument which in addition to its use in optimizing moulding conditions is also applicable to the final inspection of mass-produced components. The standard instrument has a 230 m m square viewing field and consists of a light source white light or white monochromatic versions are available - an analyser and a polarizing element, all contained in a sheet steel casing. Sharpies Photomechanics Ltd, Europa House, Unit 468 Walton Summit Centre, Bamber Bridge, Preston PR5 8AX, UK
NDT INTERNATIONAL . JUNE 1982