Please enable JavaScript.
Coggle requires JavaScript to display documents.
Chapter 2 PLANT OPERATION AND MAINTENANCE - Coggle Diagram
Chapter 2
PLANT OPERATION AND MAINTENANCE
2.0 Common hazard
Hazard of Air
Hazard of Equipment & Instruments
Hazard of Compressed Gas
Hazard of Piping,
Hazard of Piping, Valve & Hoses
2.1 Process hazard
High Flow
High flow are often desired because they imply that the facilities is maximizingproduction and revenues
Low/No Flow
Usually caused by the inadvertent closing of a valveor the failure of rotating equipment
Reverse Flow
High Pressure
Misdirected Flow
Cathodic protection (CP)
a technique used to control the corrosion of a metal surface by making it the cathode of an electrochemical cell. A simple method of protection connects the metal to be protected
Insulation gasket
designed to prevent galvanic corrosion between flanges of dissimilar metals, for example a carbon steel flange bolted to a stainless steel flange. A conducting liquid such as water must be present between the two flanges for galvanic corrosion to occur
2.2 Hazard of Utilities
Process Contamination
Electrical Power Failure
Nitrogen
Electrical Power Failure
Process Contamination
2.3 Hazard of Water
Water in Very Hot Liquid
Water and Firefighting
2.4 Hazard of Steam
-One of water’s greatest hazards is the volumetric expansion (and corresponding
-pressure increase) that takes place when it is transformed into steam.
-For example, at its boiling point of 100 degCwater vapor occupies a volume 1,600 times that of the corresponding liquid
Wet Steam in Turbines
Steaming Vessels During Turnaround
2.5 Hazards of ICE
Line Freezing
If a line contains water that is either not flowing, or is flowing very slowly, below-freezing ambient temperatures can cause the water in the line to freeze and expand.
–Therefore, during cold weather, equipment and piping that is not in use should be drained and blocked in if it cannot be heat traced.
