Locations where mainline steam traps should be installed

Locations where mainline steam traps should be installed :

For saturated steam distribution lines steam traps should be installed at the following locations:

At every 30 meters:

Installing steam traps every 30 meters ensures that condensate is removed at regular intervals, preventing its accumulation.
At every change in elevation: Condensate typically accumulates at low lying points within the distribution network. Absence of a drain pocket and steam trap at such locations will result in water hammer which damages the pipeline and leads to steam leaks.

At dead ends:

Due to the slope provided in the steam line, condensate will accumulate at dead ends within the steam pipelines. If drain pockets and steam traps are not present at these dead ends it will lead to frequent failures of the flange gaskets due to water hammer as well as result in supply of wet steam to the process.

On headers:

Typically steam headers are designed for steam velocities of 15 meters/second. This reduced velocity ensures effective separation of steam, air and condensate and thus headers should be provided with steam traps to evacuate condensate. Yet many plants do not provide steam traps at headers (see image below). This has a direct impact on the steam quality supplied to the process (wet steam) which impedes / reduces heat transfer efficiency.

Before a process equipment:

Regardless of whether it’s a batch-type or continuous process, at some point, steam to the process equipment will be shut-off, either due to the process requirement or during a shutdown. When steam is not needed and the steam inlet valve (manual valve / control valve) is shut, condensate that is formed in the line will continue to accumulate before the valve. If this condensate isn’t removed, it will flow into the equipment when the inlet valve is opened again, potentially causing damage to the pipeline, associated components, and the process equipment itself. Thus it is advisable to provide a steam trap before a manual/control valve installed on the steam supply line to a process equipment.

Along with moisture separators:

While strategically located drain pockets and steam traps will remove condensate formed in the steam pipelines, they will not remove water droplets suspended in the steam. To remove these suspended water droplets, moisture separators are installed in the steam pipelines. Steam traps should be installed along with moisture separators to evacuate this entrained moisture that gets separated from steam.