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Irrespective of the type of cathodic protection system applied to an offshore platform or pipeline the longevity and effectiveness of that system, and therefore the safety and continued revenue earning capacity of the platform or pipeline, can be assured only if adequate monitoring and surveying of the performance is undertaken.

Equipment and typical results from cathodic protection surveying systems. In the simplest form, cathodic protection surveying of fixed offshore platforms is achieved by the so called ‘dipping’ technique, dipping a reference electrode into the sea and measuring a steel/sea potential with respect to it via an indicating voltmeter and a metallic connection to the topside steelwork. This procedure is allowed in NACE RP‐01–76 REF 36 but the standard does address the importance of placing the electrode close to platform members, distant from anodes and into areas of greatest shielding. The conventionally undertaken dip survey, particularly in geographic regions with substantial sea currents which cany the electrode away from structure members, is nothing better than a general indication of the overall level of protection. The probability is of errors indicating better levels than actually exist, due to the IR related voltage drops in the sea between the electrode location and the platform member.

Pipelines are important and expensive pieces of capital equipment and their owners are interested in their safe and economic operation. This requires the reliable protection of the pipes against corrosion by the use of external coatings and/or cathodic protection.

ACEL — Tay Bridge cathodic protection. Aberdeen Corrosion Engineers Ltd in conjunction with R B R (Scotland) Limited, have been awarded a major contract for structural repairs and installation of cathodic protection to supporting columns of the River Tay A92 Road Bridge at Dundee. Work commenced during July 1989, and comprises installation of expanded titanium mesh using both sprayed and poured mortar overlays.

The Accrington Brick & Tile Co Ltd. It will be unusual to find a brick manufacturer exhibiting at the UK Corrosion Exhibition. But, The Accrington Brick & Tile Co Ltd is no ordinary brick maker. Its speciality is the design and manufacture of chemical resistant bricks, tiles, paver and other components including purpose‐made linings.

Earth retaining and structural foundation works are commonly built from rolled steel piling products which are designed and manufactured to cover a wide range of structural applications. Product data must not only provide design and application information, but also steel corrosion rates in the full range of service environments and, in this context, the corrosion of steel piling has been extensively studied both from examinations of actual structures and from more fundamental studies. Corrosion researches cover both corrosion‐protected and bare steel piling and, in order to appreciate fully the value of these researches, a simplified but adequate explanation of steel corrosion is given.

The parameters for Quality Control of both the anti‐corrosion coating and, where required, concrete weight coaling, are reviewed for six major pipelines in which the authors have been directly involved. The importance of field joint anti‐corrosion coatings are discussed, particularly for concrete weight coated pipelines. The differing environment of each project is identified and includes “in‐service” temperature, water depth, mode of pipe lay, together with cathodic protection considerations. The importance of quality control is traced from initial design study to coating and includes practical aspects of on‐site quality assurance. Material selection, application, inspection, safety aspects and economics are discussed.

Acorn steps up colour powder coating production. Acorn Exal, Milton Keynes, is planning to double its colour powder coating output. This, according to the company, is because of the way demand is going. It says that the market for colour powder coatings, which are used primarily in architecture, is growing rapidly.

Introduction — Loose polyethylene sleeving Cast iron pipe protected with a works‐applied thin bituminous coating has a long and excellent record of service; in its newest form, ductile iron, it is finding the same universal acceptance.