  
The most suitable type of trap for temperature controlled applications and processes is the continuous discharge Ball Float Steam Trap with inbuilt air release ( or steam lock release, if necessary ). This trap will discharge condensate steadily as it is formed without upsetting pressure conditions in the steam space. It will not steam lock or air lock or attempt to control the discharge temperature of the condensate. Wherever possible, both waterhammer and waterlogging should be prevented by allowing the discharge from the steam trap to run away by gravity. Utilization pressure Every steam using equipment has a maximum safe working pressure. If this is lower than the main steam supply pressure, a Pressure Reducing Valve has to be fitted. This is not the only occasion when a pressure reducing valve can be used for advantage. Most steam boilers are designed to work at relatively high pressures and should not be run at lower pressures, since carryover of water is liable to occur. For this reason, it is best to generate at high pressure and fit reducing valves before any equipments of plant requiring steam at a lower pressure. Such an arrangement has the added advantage that small bore distribution pipes can be used, due to the relatively small volume occupied by steam at high pressure. Since the temperature of saturated steam is determined by its pressure, control of pressure is a simple but effective method of accurate temperature control. This fact is used to good effect on applications such as sterilisers and control of surface temperatures on contact dryers. Reducing steam pressure will also cut down the loss of flash steam from open vents at condensate collecting tanks. Although reliability and accuracy depend on correct selection and sizing, it also depends on the correct installation.
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