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Piping over pressure

To avoid this situation, some regulators are designed with a built-in over-pressure relief mechanism. Over-pressure relief circuits usually are composed of a spring-opposed diaphragm and valve assembly that vents the downstream piping when the control pressure rises above the set point pressure. [Pg.795]

Ambient temperature 20°C. For outdoor temperature —18°, multiply load value in table by correction factor. Loads based on ANSI Schedule 40 pipe for pressures up to 16bar. Schedule 80 pipe for pressures above 16bar, except Schedule 120 above 40bar in sizes 125mm and over. [Pg.319]

The high-pressure oil flows in piping through a control valve. The control valve changes the direction of oil flow. A relief valve, set at a desired, safe operating pressure, protects the system from an over pressure condition. The oil that enters the cylinder acts on the piston, with the pressure acting over the area of the piston, developing a force on the piston rod. The force on the piston rod enables the movement of a load or device. [Pg.585]

Over-pressure, a pressure exceeding the system design pressure, is one of the most serious hazards in chemical plant operation. Failure of a vessel, or the associated piping, can precipitate a sequence of events that culminate in a disaster. [Pg.368]

The development of medium and high density polyethylene pressure pipes over the last thirty years has led to an extensive database on their stress-rupture behaviour, with associated standards for their testing and the interpretation of results [1, 2], Various forms of PVC are also used. The accelerated testing of gas and water pipes is introduced as an example of a field where there is a large database of pressure testing on which current regulations are based, the number of polymers is limited and accelerated tests are widely used (unusually, with two accelerating parameters). [Pg.153]

Chatrathi, K. et al., Process Safety Progr., 1996, 15(4), 237 A study of deflagration to detonation transition in pipes, for gas/air and dust mixtures, has been made and reported. Obviously it depends upon the exact mixture, but departures from the straight and narrow generally facilitate this transition from slight to seriously destructive over-pressures. [Pg.108]

One means to obtain a desired uniform distribution is to make the average pressure drop across the holes Ap large compared to the pressure variation over the length of pipe Ap. Then, the relative variation in pressure drop across the various holes will be small, and so will be the variation in flow. When the area of an individual hole is small compared to the cross-sectional area of the pipe, hole pressure drop may be expressed in terms of the discharge coefficient C and the velocity across the hole VD as... [Pg.32]

Metals are distinguished from nonmetals by their strength, toughness, electrical conductivity and thermal conductivity. However, the dominant property that causes metals to be preferred over most nonmetals is their ability to deform in the presence of excessive stress rather than fracture catastrophically. This is the prime reason for the widespread use of metals for structural applications such as plant equipment, piping and pressure vessels. [Pg.74]

CONSEQUENCE EVALUATION. Anomalies are most often found in the consequence section of the PrHA. A common mistake is to use the successful actuation of a protection device as a consequence, thus omitting the true consequence. For example, if a pressure vessel can be over-pressured due to a system failure, the consequence is damage/destruction of the vessel, not opening of the relief valve. It is also necessary to assure that all consequences are listed for every cause. For example, a pipe break and spill of vessel contents could result in a runaway reaction due to loss of the chemical and a fire if the chemical is flammable. Finally, the consequence must be developed assuming all protection fails. A common mistake is to assume "No Consequences," if protection was successful. [Pg.71]

The capital cost of constructing the plant is depreciated over a fixed period of say 5 years. If the plant is constructed of steel pipes and pressure vessels of a characteristic diameter D, then the capital cost C is proportional to the surface area of steel used, i.e. to Dz- On the other hand, the annual capacity Q in tonnes increases in proportion to the reactor volume, i.e. to D3. Consequently, the relationship between capital cost and capacity is... [Pg.46]

Prior to the drilling of the well all geological data, including the seismic was thoroughly reviewed and analyzed. From the data at hand there was no reason to expect an influx of fluid during the second core run in the Prairie Evaporite Formation. Not only is it unusual to encounter fluids in the middle of the salt bed, the pressures encountered in this well are abnormally high for the potash exploration industry. The zero casing and drill pipe pressure was achieved when the fluid column was at 2000 kg/m3. This equates to a bottom-hole pressure of approximately 30 MPa which is hydrostatically over-pressured by about 15 MPa. [Pg.502]

Pressure Relief Valves (PRV)—protect vessels or piping from over pressuring. They open when excessive pressure threatens a vessel. The material released is normally vented to a line that empties into the flare header. [Pg.138]

The primary causes for loss of containment of fluids are pipe or flange failure, pump seal failure, explosions, fires, overfilled tanks, over-pressured tanks, and overturned drums or containers. Because loss of containment creates serious situations, the early... [Pg.233]

During retrofit, it is often required to increase the existing centrifugal pump capacity and/or head. Pump capacity can be increased by impeller replacement (if the pump casing has allowance for a bigger impeller), pump replacement or installation of more pumps in parallel. Pump head can be increased by impeller, pump replacement or installation of more pumps in series. If the pump head and/or capacity are increased, its downstream piping and equipment shall be reviewed for over-pressure protection. [Pg.68]

The fluid whose rheological data are given in Problem 3.19 is to be pumped at 0.34 m /s through a 380 mm diameter pipe over a distance of 175 m. What will be the required inlet pressure, and what pump power will be needed ... [Pg.406]

The same fluid as that used in Problem 3.19 is to be pumped through a 400 mm diameter pipe over a distance of 500 m and the pressure drop must not exceed 53kPa. Estimate the maximum possible flow rate achievable in the pipe. (Hint By analogy with the method used... [Pg.406]

In the dispense of keg beer, the relationship between gas content, temperature and pressure is very important. If for example a beer at 10 C (50°F) has to have a carbon dioxide content of 2 voL, the equilibrium pressure is 0 7 bar over-pressure (or 10 5 psig). Were the temperature to fall to 4 4 C (40°F) and the pressure maintained, the content would rise to 2 4 vol. so that the beer may be difiScult to dispense. On the other hand if the temperature rose to 15 5 C (60°F), the gas content would fall to 1 65 vol. at the dispense tap and the beer would foam uncontrollably. Fobbing of this kind is usually a result of having an incorrect balance of temperature, pressure and carbon dioxide content. However, compensation has to be made when gas pressure has to force beer along long runs of dispense pipe or up a vertical pipe. Thus for every horizontal metre an additional 0 011 bar is required and for each vertical metre, an extra 0 108 bar. If, however, the pressure required to take the beer to the dispense tap is, because of height or distance, in excess of the equilibrium pressure then a pump must be installed. [Pg.358]

Simplicity for example designing a vessel or pipe for full over-pressure instead of adopting a pressure-relief system. (As Henry Ford has supposed to have said, What you don t fit costs nothing and needs no maintenanee .)... [Pg.30]


See other pages where Piping over pressure is mentioned: [Pg.1564]    [Pg.18]    [Pg.18]    [Pg.369]    [Pg.193]    [Pg.170]    [Pg.83]    [Pg.332]    [Pg.216]    [Pg.124]    [Pg.205]    [Pg.1386]    [Pg.367]    [Pg.311]    [Pg.479]    [Pg.332]    [Pg.161]    [Pg.106]    [Pg.736]    [Pg.216]    [Pg.848]    [Pg.1568]    [Pg.741]    [Pg.412]    [Pg.959]    [Pg.31]   
See also in sourсe #XX -- [ Pg.156 ]




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