Inverted bucket steam traps

The groupings then may be described as mechanical, which will include both ball float and inverted bucket steam traps thermostatic, which will include both balanced pressure and bimetallic elements and thermodynamic or disc pattern traps (Figure 22.13). Each type of trap has its own characteristics, and these will make one pattern of trap more suitable for use on a given application than another. In practice, it is usual to find that the applications in any given plant fall into a small number of categories, and it often is possible to standardize on a quite small number of trap types. 

Inverted-bucket steam traps contain a small bucket that becomes buoyant if steam is present and shuts off a discharge valve. The presence of condensate causes the bucket to sink and the discharge valve to open. Any entrained air is removed through a small hole in the bucket. 

The flash vessel should be fitted with a float or inverted-bucket type steam trap to the condensate discharge line, and also a pressure relief valve to prevent excess pressure buildup, as may happen if the demand for LP steam drops below the flash steam production rate. 

The following units are sized using approaches given in Section 5.2 for gas-solid separations wet cyclone, spray chamber, venturi, cross flow packed column. Steam traps ball float, open bucket, inverted bucket, liquid expansion and thermodynamic. Size on condensate flowrate. The cooler the condensate, the larger the flowrate. 

There are five major types of steam traps commonly used in industrial applications inverted bucket, float and thermostatic, thermodynamic, bimetallic, and thermostatic. Each of the five major types of steam trap uses a different method to determine when and how to purge the system. As a result, each has a different configuration. 

The inverted-bucket trap, which is shown in Figure 22.1, is a mechanically actuated steam trap that uses an upside-down, or inverted, bucket as a float. The bucket is connected to the outiet valve through a mechanical linkage. The bucket sinks when condensate fills the steam trap, which opens the outlet valve and drains the bucket. It floats when steam enters the trap and closes the valve. 

As a group, inverted-bucket traps can handle a wide range of steam pressures and condensate capacities. They are an economical solution for low- to medium-pressure and medium-capacity applications, such as plant heating and light processes. When used for higher-pressure and higher-capacity applications, these traps become large, ei ensive, and difficult to handle. 

Each specific steam trap has a finite, relatively narrow range that it can handle effectively. For example, an inverted-bucket trap designed for up to 15-psi service will fail to operate at pressures above that value. An inverted-bucket trap designed for 125-psi service will operate at lower pressures, but its capacity is so diminished that it may back up the system with unvented condensate. Therefore, it is critical to select a steam trap designed to handle the application s pressure, capacity, and size requirements. 

Like the inverted-bucket trap, float-and-thermostatic traps as a group handle a wide range of steam pressures and condensate loads. However, each individual trap has a very narrow range of pressures and capacities. This makes... 

Inverted-bucket and float-type steam traps are highly susceptible to mechanical damage. If the level arms or mechanical linkages are damaged or distorted, the trap carmot operate properly. Regular inspection and maintenance of these types of traps are essential. 

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