Axial Inlet Conversion to a Centrifugal Compressor With Magnetic Bearings

1992 ◽  
Author(s):  
Tom Novecosky
Keyword(s):  
United States ◽  
British Columbia ◽  
Natural Gas ◽  
Centrifugal Compressor ◽  
Axial Compressor ◽  
Magnetic Bearings ◽  
Operating Costs ◽  
Eastern Canada ◽  
The Past ◽  
Compressor Efficiency

NOVA’s Alberta Gas Transmission Division transports natural gas via pipeline throughout the province of Alberta, Canada, exporting it to eastern Canada, United States and British Columbia. It is a continuing effort to operate the facilities and pipeline at the highest possible efficiency. One area being addressed to improve efficiency is compression of the gas. By improving compressor efficiency, fuel consumption and hence operating costs can be reduced. One method of improving compressor efficiency is by converting the compressor to an axial inlet configuration, a conversion that has been carried out more frequently in the past years. Concurrently, conventional hydrodynamic bearings have been replaced with magnetic bearings on many centrifugal compressors. This paper discusses the design and installation for converting a radial overhung unit to an axial inlet configuration, having both magnetic bearings and a thrust reducer. The thrust reducer is required to reduce axial compressor shaft loads, to a level which allows the practical installation of magnetic bearings within the space limitations of the compressor (Bear and Gibson, 1992).

Axial Inlet Conversion to a Centrifugal Compressor With Magnetic Bearings

1994 ◽  
Vol 116 (1) ◽  
pp. 152-155 ◽  
Author(s):  
T. Novecosky
Keyword(s):  
United States ◽  
British Columbia ◽  
Natural Gas ◽  
Centrifugal Compressor ◽  
Axial Compressor ◽  
Magnetic Bearings ◽  
Operating Costs ◽  
Eastern Canada ◽  
The Past ◽  
Compressor Efficiency

NOVA’s Alberta Gas Transmission Division transports natural gas via pipeline throughout the province of Alberta, Canada, exporting it to eastern Canada, United States, and British Columbia. There is a continuing effort to operate the facilities and pipeline at the highest possible efficiency. One area being addressed to improve efficiency is compression of the gas. By improving compressor efficiency, fuel consumption and hence operating costs can be reduced. One method of improving compressor efficiency is by converting the compressor to an axial inlet configuration, a conversion that has been carried out more frequently in the past years. Concurrently, conventional hydrodynamic bearings have been replaced with magnetic bearings on many centrifugal compressors. This paper discusses the design and installation for converting a radial overhung unit to an axial inlet configuration, having both magnetic bearings and a thrust reducer. The thrust reducer is required to reduce axial compressor shaft loads, to a level that allows the practical installation of magnetic bearings within the space limitations of the compressor (Bear and Gibson, 1992).

On a Polyhedral Disease of Trichiocampus viminalis (Fall.) Larvae (Hymenoptera: Tenthredinidae)

1959 ◽  
Vol 91 (6) ◽  
pp. 379-381 ◽  
Author(s):  
W. A. Smirnoff ◽  
R. Béique
Keyword(s):  
United States ◽  
British Columbia ◽  
Populus Nigra ◽  
Quebec City ◽  
Eastern United States ◽  
Eastern Canada ◽  
The Past ◽  
The North ◽  
North Eastern

The poplar sawfly, Trichiocampus viminalis Fall., is indigenous to Europe, where it is common and widespread, but is also prevalent in the north-eastern United States, Eastern Canada and British Columbia. For the past five or six years it has caused serious defoliation to Populus nigra and P. deltoides in the vicinity of Quebec City.

Degrees of Intimacy

2002 ◽  
Author(s):  
David Ehrenfeld
Keyword(s):  
United States ◽  
British Columbia ◽  
Adult Male ◽  
Western United States ◽  
Horseback Riding ◽  
The Past ◽  
Garibaldi Provincial Park ◽  
Walking Stick ◽  
Provincial Park

When we arrived in Vancouver at the start of our vacation, the tabloid headline at the newspaper stand caught our attention. “World’s Bravest Mom,” it shrieked. We stopped to read. The story was simple; it needed no journalistic embellishment. Dusk, August 19, 1996. Mrs. Cindy Parolin is horseback riding with her four children in Tulameen, in southern British Columbia’s Okanagan region. Without warning, a cougar springs out of the vegetation, hurtling at the neck of one of the horses. In the confusion, Steven Parolin, age six, falls off his horse and is seized by the cougar. Mrs. Parolin, armed only with a riding crop, jumps off her horse and challenges the cougar, which drops the bleeding child and springs at her. Ordering her other children to take their wounded brother and go for help, Mrs. Parolin confronts the cougar alone. By the time rescuers reach her an hour later, she is dying. The cat, shot soon afterward, was a small one, little more than sixty pounds. Adult male cougars can weigh as much as 200 pounds, we learn the next day from the BC Environment’s pamphlet entitled “Safety Guide to Cougars.” We are on our way to Garibaldi Provincial Park, where we plan to do some hiking, and have stopped in the park head-quarters for information. “Most British Columbians live all their lives without a glimpse of a cougar, much less a confrontation with one,” says the pamphlet, noting that five people have been killed by cougars in British Columbia in the past hundred years. (Actually, the number is now higher; cougar attacks have become increasingly common in the western United States and Canada in recent years.) “Seeing a cougar should be an exciting and rewarding experience, with both you and the cougar coming away unharmed.”However, the pamphlet notes, cougars seem to be attracted to children as prey, possibly because of “their high-pitched voices, small size, and erratic movements.” When hiking, “make enough noise to prevent surprising a cougar . . . carry a sturdy walking stick to be used as a weapon if necessary,” and “keep children close-at-hand and under control.”

Inventories may drag on US natural gas prices

2016 ◽  
Keyword(s):  
United States ◽  
Natural Gas ◽  
The United States ◽  
Gas Production ◽  
Power Sector ◽  
Content Type ◽  
The Past ◽  
Natural Gas Prices

Significance US natural gas prices have surged over the past six weeks thanks to falling supply, strong demand from the power sector and rising exports. The uptick in prices has provided a glimmer of hope to gas producers in the United States, hard hit by a prolonged slump in prices. Impacts Declining gas production and rising demand will mean increased pipeline imports from Canada over the coming months. Mexico will pay higher prices for US natural gas imports as the Henry Hub benchmark, potentially hitting demand. US producers that have more gas-producing assets in their portfolio will benefit from rising prices.

Effects of Impeller Tip Clearance on Centrifugal Compressor Efficiency

2007 ◽  
Author(s):  
Jari L. H. Backman ◽  
Arttu Reunanen ◽  
Juha Saari ◽  
Teemu Turunen-Saaresti ◽  
Petri Sallinen ◽  
...  
Keyword(s):  
Control System ◽  
Steady State ◽  
Mach Number ◽  
Centrifugal Compressor ◽  
Tip Clearance ◽  
Magnetic Bearings ◽  
Active Magnetic Bearings ◽  
Centrifugal Compressors ◽  
Compressor Efficiency

The paper describes the results of tip clearance variation experiments in centrifugal compressors. The compressors work at different peripheral Mach number speeds either with vaneless or vaned diffusers. In the experiments, the compressors were operated in a thermally steady state after which the axial positions of the shafts were changed. The changes in the performance of the compressors were recorded and analyzed. The clearance between the impeller and its housing affects the efficiency of the centrifugal compressor. The clearance is optimized to adapt to various phenomena: thermal expansions, impeller tip deflections, shaft bending and gyroscopic motions. The compressors of this study are equipped with active magnetic bearings. They contain a control system, which constantly measures and controls the position of the shaft. This gives useful information about impeller clearance variation, and the measured results are precise within 1/100 millimeters.

International Pipelines: Canada-United States

1981 ◽  
Vol 18 ◽  
pp. 146-160
Author(s):  
John Bishop Ballem
Keyword(s):  
United States ◽  
Natural Gas ◽  
Oil And Gas ◽  
Large Diameter ◽  
The United States ◽  
Eastern Canada ◽  
Demarcation Line ◽  
Quarter Century ◽  
Pipe Line ◽  
International Boundary

For more than a quarter century, large-diameter pipeline systems have been crossing and recrossing the international boundary between Canada and the United States as though that political demarcation line did not exist. Over the years these pipelines have carried large volumes of Canadian oil and gas to American markets and two of them, Interprovincial Pipe Line Limited in the case of oil, and TransCanada PipeLines Limited in the case of natural gas, have also moved Canadian source oil and gas through the United States to reach markets in eastern Canada.

Application and Advantages of Catamarans for Coastal Patrol Vessels

1996 ◽  
Vol 33 (02) ◽  
pp. 108-118
Author(s):  
Robert G. Allan
Keyword(s):  
British Columbia ◽  
Operating Costs ◽  
Standard Series ◽  
Royal Canadian Mounted Police ◽  
The Past

Although the catamaran hull has been, for the past decade, the predominant choice for ferry designs of increasingly larger dimensions, as well as other applications, its adoption for small patrol craft has been limited. This paper describes the advantages and applicability of the catamaran for typical patrol boat missions, assesses its capital and operating costs versus those of a monohull of equivalent performance, and reviews the experience of a standard series of catamaran patrol boats operating in offshore British Columbia waters by the Royal Canadian Mounted Police. RCMP Commissioner class patrol vessels at speed

A Survey of the Parasites of Freshwater Fishes from the Mainland of British Columbia

1954 ◽  
Vol 11 (6) ◽  
pp. 673-708 ◽  
Author(s):  
Ralph V. Bangham ◽  
James R. Adams
Keyword(s):  
United States ◽  
British Columbia ◽  
Introduced Species ◽  
Pacific Coast ◽  
Freshwater Fishes ◽  
The United States ◽  
Parasite Fauna ◽  
Eastern Canada ◽  
The Pacific ◽  
The Common

Examination of 5,456 fish of 36 different species during 1951 and 1952 showed 4,925 or 90 per cent to be infected with at least one species of parasite. Records include fish from many lakes and streams of the Columbia and Fraser drainages and from a few localities in the Skeena, Peace, Liard and Skagit drainages. Parasites are recorded for each species of fish from each locality. The incidence of parasitism in the fish was comparable with that found by other surveys in eastern Canada and the United States. No major differences were found in the parasite faunas of the different river systems. Most of the common parasites were forms of circumpolar or general North American distribution. Several species of parasites described only from the Pacific coast area were common in certain hosts. Introduced species of fish showed very light infections with but few species of their normal parasites. The parasite fauna of fishes of this area appears to be less varied than in eastern and southern parts of the continent.

scholarly journals First record and new host record of the obligate dulotic ant, Polyergus bicolor (Hymenoptera: Formicidae), in Alberta, Canada

2020 ◽  
Vol 133 (4) ◽  
pp. 309-312
Author(s):  
Christine E. Sosiak ◽  
Mari West ◽  
James R.N. Glasier
Keyword(s):  
United States ◽  
Host Record ◽  
First Record ◽  
Northeastern United States ◽  
Eastern Canada ◽  
New Host ◽  
The Past ◽  
New Host Record ◽  
Formica Podzolica

We describe the discovery of Polyergus bicolor, an obligate slave-making ant species, as a new provincial record in Alberta. This species was previously known mostly from eastern Canada and the northeastern United States and has been sparsely collected: only once in the past 50 years. Polyergus bicolor was discovered parasitizing Formica podzolica, which is also a new host for the species. This discovery marks a significant expansion of both range and host for P. bicolor.

Taxonomy and nomenclature of rough fescues, Festuca altaica, F. campestris (F. scabrella var. major), and F. hallii, in Canada and the adjacent part of United States

1984 ◽  
Vol 62 (8) ◽  
pp. 1739-1749 ◽  
Author(s):  
Leon E. Pavlick ◽  
Jan Looman
Keyword(s):  
United States ◽  
British Columbia ◽  
North America ◽  
Canadian Cordillera ◽  
Eastern Asia ◽  
Eastern Canada ◽  
Adjacent Part ◽  
Gaspe Peninsula ◽  
Gaspé Peninsula ◽  
Prairie Provinces

Three species of rough fescues occur in Canada and the adjacent part of the U.S.A.: Festuca altaica, F. campestris (F. scabrella var. major), and F. halli. Festuca altaica, a wide-ranging species of eastern Asia and northern North America, extends southward in the Canadian Cordillera to about latitude 52° N and is disjunct in eastern Canada (northern Québec, Gaspé Peninsula, western Newfoundland, etc.). Festuca scabrella Torr. in Hook, is a synonym of the earlier published F. altaica Trin. in Ledeb. Rough fescues of southern British Columbia, the southern prairie provinces of Canada, and northwestern U.S.A. that have been called F. scabrella belong to F. campestris and F. hallii, a neglected species. A key to the three taxa and a map of their distribution is presented.

Sign in / Sign up

Export Citation Format

Share Document