Which flowmeters cannot be purged with steam?
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A shutdown for maintenance is upcoming. When purging pipes with process steam, what types of flowmeters are not suitable for being purged with high-temperature steam?
The vortex flow meter and orifice plate flow meter need to be removed, as well as some control valves, pressure transmitters, etc
Steam purging indicates that the material flowing in this pipeline is not steam under normal conditions. Pay attention to several aspects: 1. High temperature – the temperature of the material in the pipeline; high temperatures can damage certain instruments. 2. Fast purging flow rates – instruments that are not resistant to shocks, such as target flow meters, as well as those that are sensitive to exceeding their range, such as differential pressure transmitters, can be isolated using valves.
This post was last edited by ssln123 on 2021-11-26 at 10:31. In principle, instruments must not be purged with steam; those that need to be taken out of service should be done so to avoid damage. Unless some that are dirty or caked can be purged for a short time at the allowable temperature.
It is necessary to clarify whether steam purging refers to “purging” or “replacement”. Replacing with steam is ineffective, but using steam for purging is not possible unless it is a pipe designed specifically for steam. This isn’t just a problem of damaged instruments and gauges; it also involves the ability of pipes, valves, and fittings to withstand high temperatures. It is worth noting that many non-chemical companies combine these two into one. For reference.
Yes, it’s necessary to clarify whether steam cleaning or steam purging should be used
Many chemical fluids require steam purging of the pipelines before shutdown for maintenance; if these fluids remain in the pipes, they will solidify and block them. For example, asphalt has a melting point of around 180°C, so once it cools down, it cannot be cleared using steam purging.
Having multiple projects is fine, but it’s essential to distinguish between them. If it’s as stated in the title, misunderstandings will arise. For reference.