Steam leakage

Condensa.te Return Systems. Ia a process plant, steam traps are used to drain and return condensate. Given proper appHcation and continuous maintenance, these can operate with minimal steam leakage. Correct iastaHation is also important (12). 

Steam leakage from process equipment or pipelines... 

Shaft packing To keep steam leakage to a minimum where the shaft extends through the casing Spring-backed carbon rings... 

Production of heat energy at Rohm Haas has been improved by better control of combustion in boilers, cleaning and maintenance of boilers and process heaters to maintain their efficiency, elimination of steam leakages, steam trap maintenance, and improved condensate recovery (4). 

Steam leakage 40 g/s at 0.7 kPa through a 6-mm dia. hole. Leak rate proportional to (hole diameter) x pressure. 

Check steam leakage or leaking tubes and fouled surfaces in indirect heaters... 

In this scenario, it is assumed that one of the outlet lines of a steam generator suddenly breaks. The concept of leak before break , which excludes the guillotine break of the large primary lines, cannot be applied to the steam lines because it is difficult to demonstrate that a steam leakage from a quasi-critical crack can be detected in time with certainty. This accident, therefore, has to be considered less unlikely than a primary pipe break. 

There are hundreds of steam traps all over the place in a site and many of them could malfunction if there is no best practice of maintenance in place. That is the reason why the most common energy waste is steam leakage from bad steam traps. 

Finally, a complete trap management program should consider effective condensate discharge without excessive steam leakage. This is a key part of the trap management program, which is the focus of the next discussions. 

All storage vessels must be provided with a system of heating which will maintain the contents at 20 - 25 C (65% oleum). Inside coils should never be used because of the possibility of steam leakage. Outside coils can be used, but should not be in direct contact with the tank surface to avoid the possibility of accelerated corrosion at hot spots. A high standard of maintenance will be required to avoid steam or condensate leaks under the lagging. The upper part of all 65% storage vessels above the maximum liquid level should be heated to about 90 C to prevent... 

Water spray Steam leakage Pipe whip effects Explosion Missiles... 

APIOOO structures provide adequate segregation of safety-significant SSCs in the event of the worst case steam leakage, this includes the transient differential pressure. 

The worst case steam leakage does not prevent safety-significant SSCs from achieving their safety functions. This includes spray shields and environmental qualification of electrical equipment and containment valves. 

The assessment of steam leakage is presented in Chapter 3.6 of Reference 4.4. Systems designated essential for safe shutdown in the event of pipe rupture, where in proximity to pipe work that has not been assessed to demonstrate leak before break (LBB), are protected from the effects of steam leakage by distance and protective barriers, which are appropriately... 

Outside the Nuclear Island there are no safety significant SSCs but steam leakage prevention features, e.g. pressurisation of the main steam tunnels, are incorporated to prevent such events affecting the Nuclear Island and to limit the demand on safety significant SSCs. 

The assessment of the consequential effects of a pipe whip event has been addressed separately under internal flood, water spray, steam leakage, etc. Those systems designated essential for safe shutdown in the event of pipe rupture are the reactor coolant system, the steam generator system, the passive cooling system, the protection and safety monitoring system. Class 1 dc, the uninterruptible power supply, main control room and habitability system, contaimnent penetrations and isolation valves. 

Pipe whip effects (water/steam leakage)... 

Sprii -loaded labjrinih-type gland seals are used to minimize air leakage into and steam leakage from the steam turbine. An automatic gland steam control system and condenser can be supplied. 

This system features labyrinth-type packing to minimize steam leakage outward and air leakage inward. It vents high-pressure steam leakage to seal the low-pressure packing while the steam turbine is in operation. See Fig. T-64. 

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