Pressure rupture

Rupture Disks A rupture disk is a device designed to function by the bursting of a pressure-retaining disk (Fig. 26-15). This assembly consists of a thin, circular membrane usually made of metal, plastic, or graphite that is firmly clamped in a disk holder. When the process reaches the bursting pressure of the disk, the disk ruptures and releases the pressure. Rupture disks can be installed alone or in combination with other types of devices. Once blown, rupture disks do not reseat thus, the entire contents of the upstream process equipment will be vented. Rupture disks are commonly used in series (upstream) with a relief valve to prevent corrosive fluids from contacting the metal parts of the valve. In addition, this combination is a reclosing system. 

Pressure rupture of even a small pieee of equipment may result in a serious explosion generating missiles travelling at high veloeity. This is an important eonsideration when using laboratory glassware or industrial glass equipment and pipework. 

Pressure rupture, due to rapid release of high pressure. Blast is generated by rapid expansion of gas down to atmospherie pressure and rupture of the eontainer generates missiles. 

J H Marsh and McLendon (M M, 1997), every five years, reviews and analyzes the 100 largest properly damage losses in the hydrocarbon- chemical industries that occurred over the previous 30 years. Most of the losses involved fires or explosions, flood, windstorm, and pressure rupture losses. 

Figure 7-11. Safety valve and rupture disk installation using pressure rupturing disk on inlet to safety relief valve, and low pressure disk on valve discharge to protect against back flow/con-osion of fluid on valve discharge side, possibly discharge manifold. By permission, Fike Metal Products Div., Fike Corporation, Inc.

Pressure rupture, due to rapid release of high pressure. 

Over-pressurization, See also Pressure rupture, 46 Ozone, 16 hazards, 303 physical properties, 303 physiological properties, 304 precautions, 304... 

Pressure rupture, 46, 47, 49, 57, 219 Pressure System Safety Regulations 2000, 423 Pressure systems, 17, 423 Process design, 135, 244, 397 Process hazards, 45, 243, 398 Protective clothing, 437... 

Addition of sulfuric acid to the cyano-alcohol caused a vigorous reaction which pressure-ruptured the vessel [1]. This seems likely to have been caused by insufficient cooling to prevent dehydration of the alcohol to methaciylonitrile and lack of inhibitors to prevent exothermic polymerisation of the nitrile [2],... 

The maximum rate of pressure increase indicates the robustness of an explosion. Thus the explosive behavior of different materials can be compared on a relative basis. The maximum rate is also used to design a vent for relieving a vessel during an explosion before the pressure ruptures the vessel or to establish the time interval for adding an explosion suppressant (water, carbon dioxide, or Halon) to stop the combustion process. 

LNG tanks are designed for fairly low pressures, typically less than 1.72 MPa (250 psi), otherwise their advantage over storing natural gas as CNG would be lost. As LNG warms, vapor is produced that builds up pressure in the tank. To protect the tank from rupture due to over-pressure, vent valves are included that will release some vapor when the maximum set pressure is reached. Vent valves come in two types those that reseat when the pressure in the tank falls below the maximum, and those that don t. The second type is used only to protect the tank from over-pressure rupture, while the first type is used to control the pressure in the tank. Often they are used together in the same tank. Both types of vent valves may be made from stainless steel, brass, and aluminum materials compatibility problems are rare because of the cleanliness of LNG. 

In designing a reactor, the vessel must be able to withstand both vacuum and a very slight positive pressure. The reactor must be fitted with a blow-off valve to vent any excess of nitrogen padding gas. In case the reaction runs out of control, the lid of the reactor also must be fitted with a pressure rupture disk. The fumes and product must be trapped safely. 

The type of material used for the factory screw is unknown. We ve chosen 3/8" x 16 threaded brass rod. Note that the center section is prenotched to break under pressure. The correct diameter of the notched area will have to be determined by testing. The screw should hold the pistons together until the propellant is fully ignited, yet it MUST break before excess pressure ruptures the casing. 

Kieffer, J., and Angell. C. A.. Generation of fractal structures by negative pressure rupturing of SiO2 glass. 7. Non-Cryst. Sol 106,336 (1988). 

A vaporizing liquid is considered next. If a tank initially under high pressure ruptures, it is possible that as a result of the sudden depressurization the liquid or liquid-vapor mixture initially in the tank may partially or completely vaporize. Such explosions are known as boiling liquid-evaporating vapor explosions (BLEVEs). Here we estimate the energy released on a BLEVE. 

---