Diagnosis of the pipes coming out of the ammonia vaporization station.
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This post was last edited by shiworkstation on 2016-12-28 at 12:06. I was assigned a task to help a factory diagnose the ammonia pipes coming out of the ammonia vaporization station. The range includes the overhead pipelines from the ammonia vaporization station to a device. What problems usually occur with these ammonia pipelines? Possible problems that come to mind include: 1. Ammonia pipelines must not pass through firewalls ； (Rigid requirement, Code for Building Design 6.1.5) 2. Ammonia pipelines shall be electrically grounded ； 3. Butt-welded flanges are used for ammonia pipelines ； (PN25 nominal pressure – is a welded flange absolutely necessary?) A flat welding flange with a neck would work, right? ) 4. Fully threaded studs shall be used for ammonia pipelines, fitted with Type II hex nuts. 5. There are requirements regarding the clear height of pipes crossing roads (minimum 4.5 meters, usually 5 meters). 6. Special valves designed for ammonia should be used for ammonia pipelines. Are there any requirements regarding the distance between ammonia pipelines and buildings, as well as the distance from other pipelines? Are there any other questions? Please help to add more information; I’ll create a table so that I can compare everything on site. Any possible problems are fine.
I think the previous points made by the original poster are sufficient; there’s no need for insulation for ammonia gas
I haven’t been to the site, I don’t know how to conduct inspections, and I’m not very familiar with this. You can refer to the replies from users above; they can help you
Pretty comprehensive – are there any differences between liquid ammonia and gaseous ammonia?
You need to pay attention to some structural flaws!
3. Butt-welded flanges are used for ammonia pipelines； (PN25 nominal pressure – is a welded flange absolutely necessary?) A flat welding flange with a neck would work, right? ) It is recommended to use necked butt weld flanges for two reasons: 1. The welds need to be heat-treated, and flat welds are difficult to heat-treat. 2. The flange joint composed of a flange, gasket, and studs/nuts is a single unit; butt-welded flanges lack rigidity. If high-strength fully threaded studs are used, it is difficult to control the preload, leading to leaks.
Is it necessary to consider the effect of temperature and install expansion bends or something like that?:lol
Many small tubes of liquid ammonia are exposed, with a layer of frost on them