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Don?t Forget To Test It!
2006-11-06 00:54:02
Preventive or corrective maintenance on processing equipment should always be followed up by testing it. For example when we open a pressure vessel, do not forget to conduct hydrostatic or pneumatic pressure test. This is to ensure no leakage from gasket, seal, or any connections to the equipment. Use manufacturer standard or manual when performing the test
More About: Test , Forge

Control Valve Opening
2006-11-06 00:54:02
Two years ago, we had a plant trouble. A liquid over flew from a tower into gas line when a panel operator tried to introduce nitrogen gas into the tower prior to catalyst charge. Nitrogen gas flow is controlled by a pneumatic control valve. He made wrong operation on the control valve during switching gas flow from self-circulation to gas feeding to the tower. He continued to increase control valve opening because he saw no flow indication even though the opening was near 60%. He forgot that when he opened the control valve the gas came into the tower.
More About: Open , Opening , Control , Valve

Valve Erosion
2006-11-06 00:54:02
There are two cyclones in our plant site. The cyclones separate dehydrogenated catalyst from liquid mixtures. The mixture forms a slurry, with catalyst concentration about 100 g/l. Because of over design, the bottom valves of both cyclones should be throttled for about 30 degree. But the valves has been eroded by the catalyst slurry, and forced the plant operation to be stopped. We have tried to overcome this problem by lowering catalyst concentration and made a plan to install a reducer at the bottom pipes of the cyclones instead of valves throttling.
More About: Eros , Sion , Valve

Flammable and Combustible Liquids
2006-11-06 00:54:02
National Fire Protection Association has classified that flammable liquids are defined as liquids having closed cup flash points below 100degF (37.8degC) and vapor pressures not exceeding 40 psia (2.76 bar). Comb ust ible liquids are defined as liquids having closed cup flash points at or above 100degF (37.8degC).
More About: Bust , Liquid , Liquids

Basic Concept of Fire Loss Control
2006-11-06 00:54:02
There are five basic concepts of fire loss control, Management (Safety management), Construction (Building structure), Occupancy (Occupancy, Process), Protection (Fire protection) and Exposure (Fire exposure).Management is related with safety management organization and regulations, safety education and training, self-inspection system, etc.Construction is related with proper layout of factory facilities, fire resistance of buildings, fire separation, etc.Occupancy is related with such area as fire load reduction (house keeping, stock control, etc), control of ignition sources, maintenance of equipments, etc.Protection is related with installation and maintenance of fire fighting equipment and fire alarm systems, cooperation with a public fir department, etc.Exposure is related with preventive measures against external exposure, e.g. fire, arson, storm, flood, earthquake, etc,
More About: Basic , Loss , Control , Once

Concept and Unit of Pressure
2006-11-06 00:54:02
In chemical plant operations, pressure measurements are usually stated in Gauge Press ure (G). So it is very important to fully understand the basic concept of pressure. There are three kinds of pressure units, namely absolute pressure, differential pressure and gauge pressure. Absolute pressure takes as its basis zero pressure of a pure vacuum. Differential pressure is the difference between two pressures. Gauge pressure is the difference between an absolute pressure and the actual atmospheric pressure.Gauge pressure has a positive value if the absolute pressure is greater than atmospheric pressure and has a negative value it the absolute pressure is smaller than atmospheric pressure. Negative pressure may no longer be used as a term of a dimension, but only as a qualitative term for a relative condition. Negative value exists in the suction line.
More About: Once , Concept , Sure , Unit

Canned Pump Installation
2006-11-06 00:54:02
When we plan to install a new canned pump, we should consider some important factors that will be affected pump performance operation:1. Confirm that the pump specification meets the operation requirements.2. You have already provided a standardized foundation for the pump.3. Install the pump as near as possible with the tank suction, to have bigger NPSH available.4. Let the pump free from pipe stress or weight.5. Provide enough space around the pump for pump maintenance and disassembling work.6. Make sure to install valve at the suction and discharge line, a suction pump strainer if the pumping liquid contain foreign material, at least a pressure gauge at the pump discharge line and a sample line with needle valve if necessary. Even no foreign material during normal operation exist, it had better to install a temporary suction strainer until we can confirm that no foreign material left.
More About: Tall , Cann , Anne , Pump , Alla