COMMON NAME;
FLOAT COLUMN?
PIPE COLUMN?
SWITCH COLUMN?
STAND PIPE?
The purpose of float column is:
To accurately measure the level of the liquid in a pressure vessel
The position and orientation of the column must be appropriate to the specific application and installation criteria
The pipe column must always be in a vertical position.
It must be in a serviceable location and out of the way of any possible damage by material handling vehicles such as lift trucks.
Have several sight glasses well-spaced along the height of the pipe column to determine the level of the liquid (These are an essential part of any well-designed pressure vessel system and the use of an electronic liquid level control does not eliminate this need.)
The pipe connection at the top of the pipe column, equalizing the vapor spaces, must be well above the highest switch point on the vessel upon which it is to be mounted. The piping for this line should never be trapped, as any liquid in such a trap can cause the pipe column to become vapor bound.
The liquid equalizing line at the bottom of the pipe column must be well below the lowest switch point level on the vessel on which it is to be mounted. This line must be free draining and offer no obstruction to a gravity flow of liquid. It should not be trapped, particularly on an ammonia system, as it would then become an ideal location for oil to accumulate and could cause false levels in the pipe column.
It is recommended that a drain connection be installed at the low point on the pipe column so that the pipe column can be drained when service is required
Both the vapor and the liquid equalizer lines should be as short as possible.
Heat will readily cause a volatile liquid, such as a refrigerant, to boil.
Thus, it is important to impede the transfer of heat to a cold refrigerant whose level is being measured.
A cold liquid refrigerant contained in an uninsulated pipe column that is located in a warm compressor room is a good example of an improper installation!
It is important to properly insulate the pipe column
