Pipelines/pipework

The protection station must be carefully maintained (see Section 10.5). The function of the rectifier should be monitored at monthly intervals. The pipe/soil potentials of the pipelines should be measured at least once a year. The IR-free potentials should be determined as far as possible by the switching method, especially when new pipework is installed and connected to the protection system. 

PRESSURE SYSTEM Defined in the Pressure System Safety Regulations 2000 as a system containing one or more pressure vessels of rigid construction, any associated pipework and protective devices the pipework with its protective devices to which a transportable gas container is, or is intended to be, connected or a pipeline and its protective devices which contains or is liable to contain a relevant fluid, but does not include a transportable gas container. Here relevant fluid is steam any fluid or mixture of fluids which is at a pressure of >0.5 bar above atmospheric pressure, and which fluid or a mixture of fluids is a gas, or a liquid which would have a vapour pressure of >0.5 bar above atmospheric pressure when in equilibrium with its vapour at either tlie actual temperature of the liquid or 17.5°C or a gas dissolved under pressure in a solvent contained in a porous substance at ambient temperamre and which could be released from the solvent with the application of heat. 

At the completion of the transfer of dangerous liquids the berth operator should render pipework, valves and associated equipment safe valves and tanks should be closed and shore pipeline blanked off. 

First, the selection of the wrong pipeline was influenced by a number of factors such as poor labeling and layout. A "spaghetti" of confusing pipework was already on the charging manifold as a result of a number of concurrent... 

At A, develop a method for facilitating selection of correct pipework such as a light system activated by the person giving the instruction, or a key system that requires a key from a specific valve to operate the coupling on the pipeline related to this valve... 

Military/government type publication. It lists accidents with fatality scenarios that occurred during operation and maintenance of U.S. interstate gas pipelines from 1950 to 1965. Also listed are individual pipework failures during that time, about 3000 entries, that have been compiled from various sources by the study committee. 

Performance of Pipework in the British Sector of the North Sea Offshore Oil and Natural Gas Failure rates based on 27 actual incidents from UK DOE reports Offshore oil. gas. and process fluid submarine pipelines within the UK Continental Shelf 109. 

A glance at the vapor pressure curve for butane will, however, reveal that in winter there is a possibility of butane vapor liquefying after the vaporizer if the temperature is allowed to fall in the pipeline, even at moderate pressure. For this reason, such pipework is usually heated, either by electrical tapes or, if available, by steam or hot-water lines. 

Consumer installations which supply LPG to more than one user (e.g. metered estates, holiday home parks, caravan sites) require the gas supplier (i.e. the site owner/operator, not the LPG supplier) to obtain prior consent from the Office of Gas Supply (Ofgas) and, for the necessary pipework installation, from the Department of Energy, Pipelines Inspectorate. 

Where an isolating valve is installed in the discharge pipework the pipeline on the compressor side of the valve shall be protected by a suitable safety valve. This safety valve must be of sufficient size to pass the full output of the compressor without the pressure rising more than 10 per cent above the maximum allowable working pressure. 

Perhaps the most widely known measurement technique is that adopted by the West German Gas Industry and developed by Steinrath for buried pipework. This assigns a value (See Table 2.20) to each parameter measured the summation of these values determines the corrosivity of the soil. The parameters measured are shown in Table 2.20. Although this technique was developed for the pipeline industry it can be used with some success for general soil corrosivity assessment. 

BS 2494 1990. Specification for elastomeric joint rings for pipework and pipelines. 

Good initial design of pipework and vessels facilitates preparation of equipment for maintenance and repair. The positioning of flanges so that blanks can be inserted in pipelines and the provision of drain cocks or plugs at low points are typical of items to be considered at the design stage. 

High pressure in terminal pipework during pipeline delivery Number of deliveries where terminal pipework pressure exceeded (5 bar) during pipework deliveries Number of job observations undertaken of terminal staff carrying out management of pipeline delivery/terminal distribution activities (Tell me/Show me) undertaken on time (more frequent for newly recruited staff). Inspection and maintenance of Low MV signai direct control loop carried out to schedule. 

The behaviour of material conveyed in a non-suspension or dense phase mode of flow was investigated qualitatively in a small test rig. A conveying pipeline, constructed from glass pipework of 25mm bore, ineluding bends, was used. A binary mixture of salt and black plastic beads was chosen for its segregation characteristics and ease of observation. The salt had a mean particle size of 367pm and the beads had a diameter of approximately 5mm. 

Only a very thin film of oil is needed to produce an explosion in the pipework of compressed-air systems, even if the oil is not dispersed into the air prior to ignition. Many industrial fires and explosions have occurred in systems utilizing oil-lubricated air compressors. Therefore, adding air to an empty hydrocarbon line, or to purge a hydrocarbon line, is potentially hazardous because trace amounts of flammable materials may be clinging to the pipe walls. On one occasion, an explosion occurred in a cmde-oil pipeline to which air had been added, even though the line had been first emptied by displacement with water between two scraper plugs. 

On the other hand, the sheer size and complexity of the process pipework and the need for daily operation of cleaning, sterilising and product processing, calls for additional safeguards compared with simple manual process plant. Care with plant layout and the use of welded pipelines can contribute to better performance as can segregation of "returned product from normal production. 

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