Design pressure protection system

Complete the conceptual design requirements for a SIL 3 High Integrity Pressure Protection System (HIPPS) required to protect a main separator fed from multiple well heads from over pressuring. A simplified P ID for the installation is shown in Figure 13-22. 

To estimate the rate of DU-failures is a challenging task. First, DU-failures are rare events since the SIS is designed for high reliability. Second, there may be only a few components of the same type for observation. Whereas an installation may have more than 100 fire detectors, the number of certain valves, for example high integrity pressure protection system (HIPPS) valves, may be limited to one or two. 

The main duty on manufacturers or suppliers is to ensure that equipment destined for use in potentially explosive atmospheres satisfies relevant Essential Health and Safety Requirements, which are listed in Schedule 3 of the Regulations. The Requirements relate to three groups common requirements, supplementary requirements for equipment, and supplementary requirements for protective systems. Protective systems are defined as design units which are intended to halve incipient explosions immediately and/or to limit the effective range of explosion flames and explosion pressures. Protective systems may be integrated into equipment or separately placed on the market for use as autonomous systems. 

Where hazardous conditions can develop within a process, a protective system of some type must be provided. Sometimes these are in the form of process hardware such as pressure rehef devices. However, sometimes logic must be provided for the specific purpose of taking the process to a state where the hazardous condition cannot exist. The term safety interlock. system is normally used to designate such logic. 

As an alternative means of protection, it is economical in some cases to specify an increased equipment design pressure which will withstand the maximum pressure that can be generated, without reheving any contained fluids. Also, in some cases, the cost of the collection system can be reduced by specifying higher design pressures which will permit a higher back pressure in the collection system. 

Car-Sealed Closed Valve - In certain cases it may be advantageous to use car sealed closed valves, such as in a bypass around a fuel gas control valve used for furnace flameout protection. The bypass is provided so that the automatic shutdown system can be periodically checked for operation. Where CSC valves are used for other purposes, they are also limited to appUcations where inadvertent opening of the CSC valve would not overpressure the equipment by more than 1.5 times design pressure. 

A valve designed to protect water system components from excess pressure. 

A pressure relief system must be designed to protect the beverage bottle from overpressure. The relief device will be installed in the C02 line where it enters the beverage container. 

The reactor system in a pilot plant contains stock tanks that are 24 in in diameter and 36 in high. A relief system must be designed to protect the vessel in the event of fire exposure. The vessel contains a flammable polymer material. What rupture disc diameter is required to relieve the vessel properly Assume a discharge pressure of 10 psig. The molecular weight of the liquid is 162.2, its boiling point is 673°R, the heat of vaporization is 92.4 Btu/lb, and the heat capacity ratio of the vapor is 1.30. 

Dispersion, Flaring, Scrubbing, and Containment An example of an overpressure protection system designed to reduce emissions to the atmosphere and at the same time provide adequate protection to the equipment has been described [234]. The equipment indicated is used for the manufacture of ethylene-vinyl acetate-vinyl chloride polymer emulsions. The design pressures are up to 100 bar. 

For a liquid thermal expansion relief device that protects only a blocked-in portion of a piping system, the set pressure shall not exceed the lesser of the system test pressure or 120% of design pressure. 

Fire water mains should be designed to handle the maximum pressures developed by fire water pumps. Systems operating at pressures over 150 psi (1,034 kPa) are discouraged, as this would exceed the normal design pressures for most fire protection assets such as monitors, hydrants, etc. 

Fire Protection System System Design System Pressure System Control Valve Locations ... 

Thus, in order to adequately protect the equipment , the pressure, relief system should limit the pressure in the. reactor (or an associated item of equipment if it has a lower design pressure) to its maximum accumulated pressure. 

Correct SRV sizing, selection, manufacture, assembly, testing, installation and maintenance as described in this book are all critical for the optimal protection of the pressure vessel, system, property and life. This book explains the fundamental terminology, design and codes to allow most engineers to make the correct decisions in applying SRVs in the process industry and to improve the safety to higher levels. 

Nowadays, pressures and flow in the process industry are controlled by electronic process systems and highly sophisticated instrumentation devices. Almost all control systems are powered by an outside power source (electric, pneumatic, hydraulic). The law requires that when everything fails regardless of the built-in redundancies, there is still an independent working device powered only by the medium it protects. This is the function of the SRV, which, when everything else works correctly in the system, should never have to work. However, practice proves the contrary, and there are a variety of incidents which will allow the system pressure to exceed the design pressure. 

An SRV is a safety device designed to protect a pressurized vessel or system during an overpressure event. An overpressure event refers to any condition which would cause pressure in a vessel or system to increase beyond the specified design pressure or maximum allowable working pressure (MAWP) (Section 3.6). 

As with double-wall containment systems, a transfer vessel s construction materials, design pressure, and temperature rating should at least equal those of the equipment being protected. Construction materials can differ if the transfer vessel will only be exposed to the corrosive process for an acceptably short duration. 

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