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Low cost automatic control in mining
MAHER, A. D. and WALKIN, P. ultrasonic welding of thermoplastics.
ROBINS, P. J.
British Plastics,
38,
No. 7, 436 (1965)
Recent developments in the different techniques and types of equipment used in ultrasonic welding of plastics are discussed. Both contact and transmission welding are described; on some materials good joints have been made at distances of up to 10 in from the transducer. No solvents or plasticizers are used, there is minimum of distortion and no cleaning is required before welding takes place. Materials such as polyester films or plastics coated papers which are normally difficult to join can be welded ultrasonically by unskilled labour. (5 figures, 1 table) (Ultrasonics 1966, abstract
Temperature measurements by Electronics, 3, No. 10,482 (1965)
ultrasonics.
Industrial
Temperatures between - 211°C and + 1500°C can be measured by ultrasonics. The method gives high accuracy, fast response and no drift. It consists of a known length of metal bar or wire with a shoulder or a kink at one end. One end of the bar or wire is placed in the medium whose temperature is to be measured and the other end is coupled to a magnetostrictive transducer. Transit times of ultrasonic pulses (150-250 kc/s) are measured by superimposition on a c.r.0. (2 figures) (Ultrasonics 1966, abstract 455)
451)
SCHAPER, MAY, J. E.
Ultrasonic travelling-wave devices for communications. Institute of Electrical and Electronics Engineers Spectrum, 2, No. 10, 73 (1965).
A comprehensive paper on the latest developments, techniques and materials used in the fabrication of ultrasonic transducers and delay lines. Characteristics and principles of operation of currently available delay and amplification devices are discussed. No upper frequency limit has yet been established but already some experiments in the gigacycle frequency range at room temperature show the possibility of 200 Mb/s bit rate, resulting in the total storage capacity of 24,000 bits. Ultrasonic travelling-wave amplifiers and other phonon interaction devices also show great possibilities. (16 figures, 37 references, 3 tables) (Utrasonics
H.
Ultrasonic Schweissen
inspection of welds in thin walled and Schneiden, 17, No. 3, 119 (1965)
pipes.
Testing of thin walled tubes presents great difficulty because at these cross-sections and angles of incidence the ultrasonic beam does not fully obey the laws of geometric optics. In this paper the author attempts to analyse the structure of the beam, the reflection conditions and interference echoes, especially at angles of incidence greater than 45”. Longitudinal, induction and circumferentially welded tubes from 6-5 in to 23 in O.D. and wall thickness O-14-0-24 in have been examined. The use of focused beam and ultrasonic lens is discussed but above all a thorough understanding of the propagation conditions is recommended. (9 figures, 2 references) (Ultrasonics 1966, abstract 456)
1966, abstract 452)
SILBER, F. A. MUENOW,
R. A.
A preliminary
study of resistance welds by improved ultrasonic image conversion techniques. Materials Evaluation, 23, No. 9,449 (1965)
A television type equipment that is sensitive to ultrasonic waves is described. It makes possible direct visualization of size and shape of any discontinuity or inclusion inside opaque objects. It works in the range 0.9-10 MC/S and at 5 MC/S can resolve to 0.010 in. Recent improvements of the system are larger sensitive areas and some impedance matching layers called interference depressors which almost eliminate standing wave interference problems. Applications to spot weld evaluation are discussed. (5 figures, 18 references) (Ulrrasonics 1966, abstract 453)
Ultrasonic testing of flat rolled steel. Berg iind Hiittenmiinnische Monatshefte, ZlO, No. 3, 66 (1965) An automatic testing and recording installation using
16-channel ultrasonic pulse-echo flaw-detectors is described. The installation can inspect at 12 m/min, accommodate flat sheets up to 1620 mm wide and 80-250 mm thick. The hydraulically operated ultrasonic probes (16 transmitting and 16 receiving) are mounted in V shape to each other and coupled by degassed water. Particular reference is made to automatic recording of information. (8 figures, 5 references) (Ultrasonics
1966, abstract 457)
SIMPSON, R. J.
Electroplating and ultrasonics. Finishing, 18, No. 9, 305 (1965) REEVE, G. R.
Low cost automatic control in Practice, 19, No. 11, 1019 (1965)
mining.
Instrument
An ultrasonic control and switching system has been found satisfactory for work in coal mining. It is not affected by coal dust, rain, snow or fog. For a total cost of under f3,OOO this automatically controlled system has replaced four men and increased the wagon filling capacity by S-10%. Six sets of sensors activate limit switches as the ultrasonic beam is interrupted by different sizes of wagon. The system should be adaptable to many other industries. (4 figures) (Ultrasonics 1966, abstract 454)
Electroplating
and Metal
Effects of ultrasound on electrodeposition processes are discussed. There appear to be two main areas of application; low frequency (20 kc/s) where ultrasonic produces mainly agitation, and high frequency (low megacycle range) where standing wave effects can be made use of. At low frequency, apart from the benefits of agitation, higher current densities (six times higher) can be used, and small grain, better quality deposits are possible. In the higher frequency range metals can be deposited in stripes corresponding to the standing waves which at 10 MC/S gives 134 lines/cm. (3 figures, 6 references). See also: “Using ultrasonic waves as a ruling machine,” Instrument Practice, 19, No. 9, 835 (1965) (Ultrasonics
1966, abstract 458)
I.JLTRAsoNIcs/January
1966
ROBINS, P. J.
British Plastics,
38,
No. 7, 436 (1965)
Recent developments in the different techniques and types of equipment used in ultrasonic welding of plastics are discussed. Both contact and transmission welding are described; on some materials good joints have been made at distances of up to 10 in from the transducer. No solvents or plasticizers are used, there is minimum of distortion and no cleaning is required before welding takes place. Materials such as polyester films or plastics coated papers which are normally difficult to join can be welded ultrasonically by unskilled labour. (5 figures, 1 table) (Ultrasonics 1966, abstract
Temperature measurements by Electronics, 3, No. 10,482 (1965)
ultrasonics.
Industrial
Temperatures between - 211°C and + 1500°C can be measured by ultrasonics. The method gives high accuracy, fast response and no drift. It consists of a known length of metal bar or wire with a shoulder or a kink at one end. One end of the bar or wire is placed in the medium whose temperature is to be measured and the other end is coupled to a magnetostrictive transducer. Transit times of ultrasonic pulses (150-250 kc/s) are measured by superimposition on a c.r.0. (2 figures) (Ultrasonics 1966, abstract 455)
451)
SCHAPER, MAY, J. E.
Ultrasonic travelling-wave devices for communications. Institute of Electrical and Electronics Engineers Spectrum, 2, No. 10, 73 (1965).
A comprehensive paper on the latest developments, techniques and materials used in the fabrication of ultrasonic transducers and delay lines. Characteristics and principles of operation of currently available delay and amplification devices are discussed. No upper frequency limit has yet been established but already some experiments in the gigacycle frequency range at room temperature show the possibility of 200 Mb/s bit rate, resulting in the total storage capacity of 24,000 bits. Ultrasonic travelling-wave amplifiers and other phonon interaction devices also show great possibilities. (16 figures, 37 references, 3 tables) (Utrasonics
H.
Ultrasonic Schweissen
inspection of welds in thin walled and Schneiden, 17, No. 3, 119 (1965)
pipes.
Testing of thin walled tubes presents great difficulty because at these cross-sections and angles of incidence the ultrasonic beam does not fully obey the laws of geometric optics. In this paper the author attempts to analyse the structure of the beam, the reflection conditions and interference echoes, especially at angles of incidence greater than 45”. Longitudinal, induction and circumferentially welded tubes from 6-5 in to 23 in O.D. and wall thickness O-14-0-24 in have been examined. The use of focused beam and ultrasonic lens is discussed but above all a thorough understanding of the propagation conditions is recommended. (9 figures, 2 references) (Ultrasonics 1966, abstract 456)
1966, abstract 452)
SILBER, F. A. MUENOW,
R. A.
A preliminary
study of resistance welds by improved ultrasonic image conversion techniques. Materials Evaluation, 23, No. 9,449 (1965)
A television type equipment that is sensitive to ultrasonic waves is described. It makes possible direct visualization of size and shape of any discontinuity or inclusion inside opaque objects. It works in the range 0.9-10 MC/S and at 5 MC/S can resolve to 0.010 in. Recent improvements of the system are larger sensitive areas and some impedance matching layers called interference depressors which almost eliminate standing wave interference problems. Applications to spot weld evaluation are discussed. (5 figures, 18 references) (Ulrrasonics 1966, abstract 453)
Ultrasonic testing of flat rolled steel. Berg iind Hiittenmiinnische Monatshefte, ZlO, No. 3, 66 (1965) An automatic testing and recording installation using
16-channel ultrasonic pulse-echo flaw-detectors is described. The installation can inspect at 12 m/min, accommodate flat sheets up to 1620 mm wide and 80-250 mm thick. The hydraulically operated ultrasonic probes (16 transmitting and 16 receiving) are mounted in V shape to each other and coupled by degassed water. Particular reference is made to automatic recording of information. (8 figures, 5 references) (Ultrasonics
1966, abstract 457)
SIMPSON, R. J.
Electroplating and ultrasonics. Finishing, 18, No. 9, 305 (1965) REEVE, G. R.
Low cost automatic control in Practice, 19, No. 11, 1019 (1965)
mining.
Instrument
An ultrasonic control and switching system has been found satisfactory for work in coal mining. It is not affected by coal dust, rain, snow or fog. For a total cost of under f3,OOO this automatically controlled system has replaced four men and increased the wagon filling capacity by S-10%. Six sets of sensors activate limit switches as the ultrasonic beam is interrupted by different sizes of wagon. The system should be adaptable to many other industries. (4 figures) (Ultrasonics 1966, abstract 454)
Electroplating
and Metal
Effects of ultrasound on electrodeposition processes are discussed. There appear to be two main areas of application; low frequency (20 kc/s) where ultrasonic produces mainly agitation, and high frequency (low megacycle range) where standing wave effects can be made use of. At low frequency, apart from the benefits of agitation, higher current densities (six times higher) can be used, and small grain, better quality deposits are possible. In the higher frequency range metals can be deposited in stripes corresponding to the standing waves which at 10 MC/S gives 134 lines/cm. (3 figures, 6 references). See also: “Using ultrasonic waves as a ruling machine,” Instrument Practice, 19, No. 9, 835 (1965) (Ultrasonics
1966, abstract 458)
I.JLTRAsoNIcs/January
1966