Piping operating safety

Typical solutions to meet the 10% rule include installation of a bellows kit or a pilot-operated safety relief valve. Alternatively, piping modifications can be considered, or a more rigorous analysis can be performed to further define the risk of chattering. 

In steam turbine power plants, steam pipes carry super heated vapor under high temperature (1050°F/565.5°C) and high pressure often at 3500 psiMPa or greater. In a jet engine temperatures may reach to 1000°C, which may initiate creep deformation in a weak zone. For these reasons, it is crucial for public and operational safety to understand creep deformation behavior of engineering materials. 

The greater the amount of carbon dioxide injected, the more will return to the surface with the methane. This creates the need for a gas-separation plant of the type shown in Figure 3.2. The removal of carbon dioxide from oil is much simpler than from methane, which is why enhanced oil recovery is practised more widely than enhanced gas recovery. With an extensive coal seam, it will be necessary to drill injection and extraction wells every few hundred metres or so. These, together with the associated gas compressors, distribution pipes and pumps, access roads, etc., will turn a rural landscape into an industrial site. When the operational/safety issues and the extent of industrialization become fully appreciated, not to mention the impact on the ecological habitat, there may well be local opposition to the recovery of coal-bed methane - with or without carbon dioxide injection and storage. 

At Zaporozhe NPP, protection of the primary circuit against overpressure during incidents is provided by three safety valves on the pressurizer For Units 1 to 4, only one valve can be opened intentionally by actuating pilots from the control room and the emergency control room The other two safety valves are acting as passive pilot operated safety valves For Units 5 and 6, they have a new design of valves All the pilots of the safety valves can be actuated from the control rooms The pilots can be isolated by an additional pilot in case of impulse pipe failure The qualification of safety valves for water flow is not confirmed... 

The final step in the plot plan arrangement is to space equipment and supporting facilities for operator and maintenance access, safety, piping flexibility and support, and platforming requirements. At this stage, the layout designer must rely on experience because the final information is not available for calculating... 

Safety. A large inventory of radioactive fission products is present in any reactor fuel where the reactor has been operated for times on the order of months. In steady state, radioactive decay heat amounts to about 5% of fission heat, and continues after a reactor is shut down. If cooling is not provided, decay heat can melt fuel rods, causing release of the contents. Protection against a loss-of-coolant accident (LOCA), eg, a primary coolant pipe break, is required. Power reactors have an emergency core cooling system (ECCS) that comes into play upon initiation of a LOCA. 

Cooling water pipes are essential for the operation of power stations and must not cease to function. Pipelines for fire fighting are also important for safety reasons. Such steel pipelines are usually well coated. At areas of unavoidable damage to the pipe coating, there is an increased danger due to cell formation between steel and concrete where local corrosion rates of >1 mm a are to be expected [4], Damage to pipelines for fire fighting has frequently been observed after only a few years in service. 

Some method of pressure relief is required on all pressure vessels and for other proeess equipment where inereasing pressure might rupture the vessel. Mueh of the piping used in modern ehemieal operations also requires overpressure proteetion. Safety relief valves or rupture dises are employed for pressure relief. In many eases, either a rupture dise or a safety relief valve ean be used. Safety relief valves are usually used for proeess proteetion and rupture dises are used for vessel proteetion. The safety relief valve or rupture dise must be designed to operate at a known pressure and prevent the pressure within the system from inereasing. Therefore, it is important to eon-sider the flowrate the valve ean handle. 

Where the oxidant concentration is continually monitored, a safety margin of at least 2 volume percent below the measured worst credible case LOG shall be maintained, unless the LOG is less than 5 volume percent, in which case, the equipment or piping shall be operated at no more than 60% of the LOG. 

This report is by Battelle Columbus Division to the Line Pipe Research Supervisory Committee of the American Gas Association. It presents an analysis of statistical data obtained from reports of lea)c or rupture (service) incidents and test failures in natural gas transmission and gathering lines over the 14.5 year period from 1970 through June, 1984. All gas transmission companies were required to notify the Office of Pipeline Safety Operations in the event of a "reportable" incident, as defined by the Code of Federal Regulations. The purpose of the study is to organize the reportable incident data into a meaningful format from which the safety record of the industry can be assessed. 

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