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Multipurpose monitoring system
[CRVOnENtCL
lnewsi Vacuum technology services
Industrial news Firm base supports LNG plants LNG plants at sea can now be as stable as their land-based counterparts. In Sener's LNG Seabed Supported System, a development of their LNG Marine system (the MLS), the liquefaction and storage barges do not float but are supported by reinforced concrete caissons resting on the seabed. These concrete caissons are sunk into the seabed where required, a layer of gravel is laid on top of each unit to equalize pressure, the storage and liquefaction barges are then ballasted onto the supports. The caissons can be deballasted out of the water and re-located or they can also be used as a drydock for inspection and routine maintenance of the barges. The advantage of this type of system as compared to land-based or the normal floating system is that it offers both flexibility and stability. The basic unit, the MLS floating plant, consists of liquefaction and storage barges welded together. This plant can accommodate
any size of LNG carrier and is both cheaper and easier to construct than a land-based plant. Also it can be easily moved to different locations. This system, the L3S, is suitable for any LNG site with a water depth up to 30 m. Plants with liquefaction capacities of up to 800 million ft 3 a day can be supplied; for a typical 400 million ft 3 per day liquefaction capacity, the LNG storage capacity would be 159 000 m 3 with an LNG offloading rate of 126 000 m 3 in twelve hours. Two storage and one liquefaction barge can be welded together to form a single unit but with reasonable seabed soil they can all be supported separately and just connected by flexible pipelines. The plants will be built at Crinavis, Spain's purpose built LNG tanker shipyard, and negotiations are already in progress for a number of plants. (Stratics Consultants Ltd, 35 Craven Street, London WC2N 5NQ, UK)
A vacuum instrumentation group has been recently established by Cambridge Consultants Ltd to undertake design and construction of special purpose vacuum technology systems. Such systems are at present mainly used for large process industries, food production, cryogenics, semiconductor fabrication, and the aerospace industry. This group which has wide experience in electron and ion optics, in addition to building systems, also offer advice on the use of vacuum processes to improve production efficiency, pilot studies of new vacuum process and technologies, evaluate different manufacturers' equipment, and provide educational and industrial troubleshooting services. Current projects include the construction of a high resolution energy dispersive electron detector, a fast electron beam pulsing system, and a study of the use of vacuum technology in metal plating. (Cambridge Consultants Ltd, Bar Hill, Cambridge, UK)
Multipurpose monitoring system Liquid nitrogen levels, water levels, flow and leakage, gas pressure and leakage, and temperature change can all be monitored simultaneously using a multipurpose system recently developed by Cambridge Technology. The system was originally developed to sense the level of liquid nitrogen in Si (Li) and Ge (Li) detector dewars and anti-contamination devices but can be programmed to provide a number of alarm references from sources such as temperature change, water flow, gas pressure etc, when supplied with appropriate sensors. It can thus provide continuous monitoring of safety levels in the laboratory and in industry.
Artist's impression of the L3S seabed supported LNG system
CRYOGENICS. MAY 1977
A dual alarm level is provided for liquid nitrogen. When the level reaches a predetermined point the digits of the clock and indicator flash on and off at half-second intervals. A second alarm is triggered if the first is ignored when the
309
ICRYOGENICi
[new
liquid reaches a lower level, and an additional audio alarm is also set-off. In addition to the basic version, a double channel version is available to provide simultaneous monitoring of two parameters, additional channels can be supplied to meet special requirements. In a multichannel system automatic switch-off can be provided for sensing gas leaks and in the case of floor level water sensors, magnetic valves are used to switch off mains water supply. (Cambridge Technology Consultants Co, Chesterton Mill, French's Road, Cambridge, CB4 3NP,
and LTS-21-DTC-01 feature performance at two levels between the first two systems.
UK)
A complete line of accessories is available to set up the basic systems for specific requirements. Possible applications include ir, uv, and vis spectroscopy, esr, epr, and esca/auger, matrix isolation, detector cooling, x-ray and neutron diffraction, Mossbauer spectroscopy, superconductivity studies, and Hall measurements. The systems are particularly useful for long term applications as no cryogenic liquids are used. (Lake Shore Cryotronics Inc, 9031 Sandrock Road, Eden, NY 14057, USA)
All systems complete
Simple detection of gas leaks
Four basic performance tested systems for for virtually any experiment in the 10 to 300 K range are available from Lake Shore Cryotronics. The systems combine CTi's Model 21 Cryodyne ® closed cycle refrigerator with Lake Shore's cryogenic thermometry and instrumentation.
Leak testing of large plants can now be carried out by a single operator using Leybold-Heraeus' Ultratest F helium mass spectrometer.
The four systems available are the LTS-21-D7C with + 0.5 K control from 10 to 300 K; the LTS-21-DTC-001 with + 0.0003 K short-term control, -+ 0.003 K control from 12 to 26 K and + 0.01 K stability from 26 to 100 K. The other two systems - LTS-21-D70C
This portable remote control unit can be used for pressure or vacuum testing at at distances of up to 30 m, using three 10 m interconnecting cables. Special features of the Ultratest F include automatic sequencing, direct read-out of leak rate in mbar 1 s, two options of integral roughing pumps (16 or 30 m3h -1), motor driven inlet valve and a liquid-nitrogen cold trap.
Leybold-Heraeus Ultratest F helium leak detector can be easily managed by a single operator
The inlet valve is pulsed when the pressure reaches 1 mbar, so that leak testing can begin at this high pressure. The nitrogen cold trap is effective for 24 hours, and gives a high pumping speed for condensable vapours. For calibration a test helium leak is available as an option. An easilydemountable ion source has two longlife iridium cathodes that are easily interchangeable. By using the LeyboldHeraeus Quick Test sniffer gun in conjunction with the Ultratest F, fast testing of pressure systems can be achieved. The smallest detectable leak rate, using the Ultratest F, is 2 x 10 -12 mbar s-1 . The instrument is suitable for use with He 3 or He4, and can also be adapted for hydrogen. (Leybold-Heraeus Ltd, 173 Greenwich High Road, London SE10 8JA) F r o z e n t o t h e core
Complete cryogenic system produced by Lake Shore consisting of (from left to right): Model DTC-500Sp temperature control, model 21 cold head, and model 21 compressor unit (a universal sample chamber is also shown attached to model 21 )
310
The analysis of salmon spawning beds in Welsh rivers with the aid of LN2 reported in the June issue last year
CRYOGENICS. M A Y 1977
lnewsi Vacuum technology services
Industrial news Firm base supports LNG plants LNG plants at sea can now be as stable as their land-based counterparts. In Sener's LNG Seabed Supported System, a development of their LNG Marine system (the MLS), the liquefaction and storage barges do not float but are supported by reinforced concrete caissons resting on the seabed. These concrete caissons are sunk into the seabed where required, a layer of gravel is laid on top of each unit to equalize pressure, the storage and liquefaction barges are then ballasted onto the supports. The caissons can be deballasted out of the water and re-located or they can also be used as a drydock for inspection and routine maintenance of the barges. The advantage of this type of system as compared to land-based or the normal floating system is that it offers both flexibility and stability. The basic unit, the MLS floating plant, consists of liquefaction and storage barges welded together. This plant can accommodate
any size of LNG carrier and is both cheaper and easier to construct than a land-based plant. Also it can be easily moved to different locations. This system, the L3S, is suitable for any LNG site with a water depth up to 30 m. Plants with liquefaction capacities of up to 800 million ft 3 a day can be supplied; for a typical 400 million ft 3 per day liquefaction capacity, the LNG storage capacity would be 159 000 m 3 with an LNG offloading rate of 126 000 m 3 in twelve hours. Two storage and one liquefaction barge can be welded together to form a single unit but with reasonable seabed soil they can all be supported separately and just connected by flexible pipelines. The plants will be built at Crinavis, Spain's purpose built LNG tanker shipyard, and negotiations are already in progress for a number of plants. (Stratics Consultants Ltd, 35 Craven Street, London WC2N 5NQ, UK)
A vacuum instrumentation group has been recently established by Cambridge Consultants Ltd to undertake design and construction of special purpose vacuum technology systems. Such systems are at present mainly used for large process industries, food production, cryogenics, semiconductor fabrication, and the aerospace industry. This group which has wide experience in electron and ion optics, in addition to building systems, also offer advice on the use of vacuum processes to improve production efficiency, pilot studies of new vacuum process and technologies, evaluate different manufacturers' equipment, and provide educational and industrial troubleshooting services. Current projects include the construction of a high resolution energy dispersive electron detector, a fast electron beam pulsing system, and a study of the use of vacuum technology in metal plating. (Cambridge Consultants Ltd, Bar Hill, Cambridge, UK)
Multipurpose monitoring system Liquid nitrogen levels, water levels, flow and leakage, gas pressure and leakage, and temperature change can all be monitored simultaneously using a multipurpose system recently developed by Cambridge Technology. The system was originally developed to sense the level of liquid nitrogen in Si (Li) and Ge (Li) detector dewars and anti-contamination devices but can be programmed to provide a number of alarm references from sources such as temperature change, water flow, gas pressure etc, when supplied with appropriate sensors. It can thus provide continuous monitoring of safety levels in the laboratory and in industry.
Artist's impression of the L3S seabed supported LNG system
CRYOGENICS. MAY 1977
A dual alarm level is provided for liquid nitrogen. When the level reaches a predetermined point the digits of the clock and indicator flash on and off at half-second intervals. A second alarm is triggered if the first is ignored when the
309
ICRYOGENICi
[new
liquid reaches a lower level, and an additional audio alarm is also set-off. In addition to the basic version, a double channel version is available to provide simultaneous monitoring of two parameters, additional channels can be supplied to meet special requirements. In a multichannel system automatic switch-off can be provided for sensing gas leaks and in the case of floor level water sensors, magnetic valves are used to switch off mains water supply. (Cambridge Technology Consultants Co, Chesterton Mill, French's Road, Cambridge, CB4 3NP,
and LTS-21-DTC-01 feature performance at two levels between the first two systems.
UK)
A complete line of accessories is available to set up the basic systems for specific requirements. Possible applications include ir, uv, and vis spectroscopy, esr, epr, and esca/auger, matrix isolation, detector cooling, x-ray and neutron diffraction, Mossbauer spectroscopy, superconductivity studies, and Hall measurements. The systems are particularly useful for long term applications as no cryogenic liquids are used. (Lake Shore Cryotronics Inc, 9031 Sandrock Road, Eden, NY 14057, USA)
All systems complete
Simple detection of gas leaks
Four basic performance tested systems for for virtually any experiment in the 10 to 300 K range are available from Lake Shore Cryotronics. The systems combine CTi's Model 21 Cryodyne ® closed cycle refrigerator with Lake Shore's cryogenic thermometry and instrumentation.
Leak testing of large plants can now be carried out by a single operator using Leybold-Heraeus' Ultratest F helium mass spectrometer.
The four systems available are the LTS-21-D7C with + 0.5 K control from 10 to 300 K; the LTS-21-DTC-001 with + 0.0003 K short-term control, -+ 0.003 K control from 12 to 26 K and + 0.01 K stability from 26 to 100 K. The other two systems - LTS-21-D70C
This portable remote control unit can be used for pressure or vacuum testing at at distances of up to 30 m, using three 10 m interconnecting cables. Special features of the Ultratest F include automatic sequencing, direct read-out of leak rate in mbar 1 s, two options of integral roughing pumps (16 or 30 m3h -1), motor driven inlet valve and a liquid-nitrogen cold trap.
Leybold-Heraeus Ultratest F helium leak detector can be easily managed by a single operator
The inlet valve is pulsed when the pressure reaches 1 mbar, so that leak testing can begin at this high pressure. The nitrogen cold trap is effective for 24 hours, and gives a high pumping speed for condensable vapours. For calibration a test helium leak is available as an option. An easilydemountable ion source has two longlife iridium cathodes that are easily interchangeable. By using the LeyboldHeraeus Quick Test sniffer gun in conjunction with the Ultratest F, fast testing of pressure systems can be achieved. The smallest detectable leak rate, using the Ultratest F, is 2 x 10 -12 mbar s-1 . The instrument is suitable for use with He 3 or He4, and can also be adapted for hydrogen. (Leybold-Heraeus Ltd, 173 Greenwich High Road, London SE10 8JA) F r o z e n t o t h e core
Complete cryogenic system produced by Lake Shore consisting of (from left to right): Model DTC-500Sp temperature control, model 21 cold head, and model 21 compressor unit (a universal sample chamber is also shown attached to model 21 )
310
The analysis of salmon spawning beds in Welsh rivers with the aid of LN2 reported in the June issue last year
CRYOGENICS. M A Y 1977