National Research Development Corporation

The Secretary of State for Defence in Her Britannic Majesty's Government

The British Petroleum Company, P.l.c.

Bp Solar Limited

Avonwood Developments Ltd

Rodney J Marshall

Jeremy Barker

Greville E Bagg

Martin Fleischmann

David J Schiffrin

Francis C Walsh

Robert E Jansson

John M Sherborne

Mehran Sadeghi

Corrosion is monitored by making a resistance measurement between a contact and an uncorroded or relatively uncorroded portion of the article to be monitored. Changes in the resistance measured are a result of the presence of a corrosion product, or the breakdown of protective coatings by corrosion. The contact may be a sensor washer which is held in place around a threaded stud 6 by nut 12. The washer comprises a steel ring 14 and an electrically conducting ring 18 which is insulated from ring 14 and contacted by circling 21 and conductor wire 23 in resin jacket 22. The measurement may be made on magnesium alloy gearboxes in helicopter. The alloy may be protected by a paint film so that the initial resistance measured is very high.

Method and apparatus for detecting and monitoring corrosion

Electrochemical process

Electrochemical generation of N.sub.2 O.sub.5

A compound containing an element of Group IIB and of Group VIB is cathodically deposited on a cathode comprising a layer of high sheet resistance on an insulating substrate by positioning the anode relative to the cathode such that the distance from the anode to a point on the cathode increases as the distance between the point and the nearest electrical connection to the cathode decreases.

A process of diaphragmless electrolysis comprises providing an electrochemical cell having substantially parallel electrodes in the form of discs axially spaced from each other and connected for common rotation about their axis, one of the discs having means defining a central opening, causing common rotation of the electrodes, introducing matter to be electrolyzed through said central opening, adjusting the speed of rotation until the profile of velocity of effective radial flow between the discs shows a double-humped distribution, and applying a potential between the discs.

Electrochemical cells and methods of electrolysis

Growing community of inventors

Southampton, United Kingdom

Rodney J Marshall