Types of leaks

Another type of leak Methane release could It happens in depleted oil and gas Characterisation... 

The requirements in (a) through (f) apply to more than one type of leak test ... 

Leak Testing Location of through wall defects and flaws while under pressure or vacuum. Various fluids and gases are used for pressure testing several types of leak detectors are used to locate a leak. 

Although chlorine is a hazardous substance, it can he handled safely. All persons who handle chlorine should he thoroughly trained in its properties, in correct use of safety equipment, and in the nperulion ol all other equipment including containers. The Chlorine Institute. 342 Madison Ave.. New York. NY 10017. publishes Ihe Chlorine Manual (available from the Insli-(ule at nominal cost) which provides useful information on these matters. In addition the Chlorine Institute has designed emergency kits capable of capping off certain types of leaks which can occur in chlorine containers. 

Passive types of leak detection such as observation wells and collection sumps where product is collected and analyzed directly should work effectively with methanol. Active leak detection systems that rely on thermal conductivity and electrical resistivity sensors will not work with methanol because its properties are so different from gasoline. Another type of active leak detection system that will work with methanol or any other type of fuel relies on changes in impedance in a sensor wire as it becomes wetted with the fuel [4.5]. These leak detection systems also have the advantage that they can pinpoint the location of the leak along the length of the sensor wire. 

All CNG refueling systems should have some type of leak detection system using methane detectors. Methane detectors should be placed strategically about the... 

Verifying that a real leak exists only tells you part of the story because there are four types of leaks. You must eliminate them by analysis of the symptoms, experience, the history of the vacuum system, and/or trial and error. The following are the four types of real leaks ... 

To prevent the risk of a gas leak, the drill-hole head is equipped with a blow-out preventer. This device is similar to that used on oil wells to avoid this type of leak, which in their case constitutes a threat of explosion or fire. In fact the risk of leakage is limited in a radiochemical sampling drill-hole, as the gas formed at the moment of the... 

In this particular system we are concerned about two types of leaks KOH fluid leaks and gas leaks of hydrogen and/or oxygen. Following are the main causes of fugitive emissions (leaks) ... 

The reason for allowing the vapour to equilibrate before shaking is that the solvent is a volatile liquid with an appreciable vapour pressure (40 ram Hg at 31.8°C for toluene). Therefore if a vial is capped and shaken immediately, a pressure in the region of half a pound per square inch can be produced inside the vial (Findlay, 1904) and this will force out some of the contents if the seal is not perfect. In practice this is a monotonously frequent occurrence. However if the vapour is properly equilibrated this type of leak doesn t occur because any fluid that leaves the vial must be replaced by air otherwise a slight vacuum is created. The effect therefore is to hold the liquid in the vial. The volatility of the solvent is also the reason for keeping caps on the vials between additions. The constitution of these mixtures is critical.and if some of the solvent is lost by evaporation the composition will be altered. 

Considering these different types of leak monitoring systems in more detail it will become clear that in most cases only electrical systems are practically capable of providing adequately accurate control for large-area geomembrane liners. Therefore only the requirements on these systems will be analysed in more detail in later sections of this chapter. 

The first type of leak monitoring system requires sensors applied beneath the geomembrane which exhibit specific reactions to changes in the subgrade due to water input through a hole. This concept has been used by various manufacturers of which three examples will be briefly discussed. 

It is not likely that one can find this type of leak by sampling for amine strength at different points in the refinery. The entire amine system volume may circulate through the scrubber and regenerator 20 times a day. A small loss in amine strength per pass cannot be detected by the lab. This small loss in strength is, however, multiplied by 20 each day. 

A ring joint for connecting stainless steel and titanium piping at temperatures up to 650°F has also been developed [28] for possible use with titanium letdown heat exchanger in the HRE-2. The different thermal coefficients of expansion of the two materials are bridged by use of a stainless-steel clad carbon-steel flange in the stainless half of the joint. An HRE type of leak detector is placed in the clad flange. 

Earlier in this chapter it was noted that offshore safety management and the implementation of an SEMS program have much in common with other process industries, particularly onshore facilities such as refineries, pipelines, and chemical plants. However, each industry does have its own unique safety issues and problems. For example, a chemical plant will often either manufacture or use some highly toxic compotmds that have to be handled with special equipment or materials of construction. Refineries have many processing steps that often operate at higher temperatiues and pressures. And the pipeline business works in an enviromnent where most of its operations are in public locations and close to where people Uve and work, so any type of leak is likely to quickly have a significant public impact. 

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