Classification of pressure vessels and pressure pipelines
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I’ve recently encountered a problem in design that has left me puzzled: how to divide pressure vessels and pressure pipelines into zones. Specifically, I’m not sure what exactly is included within the scope of pressure pipelines. For some equipment, such as skid-mounted units, the piping system is very simple; the total length of all pipes for the inlet and outlet of the fluid is only about 10 meters. How should such systems be designed in accordance with the relevant standards? Also, it was previously believed that pressure pipelines referred to certain regular transmission lines, and it seems that the design of pipelines within installations follows the requirements for pressure pipelines. 1. Are some of the simple pipelines attached to pressure vessels, such as vent pipes, safety valve pipelines, and discharge lines, considered pressure pipelines? 2. Does the piping design we often talk about also need to be carried out in accordance with the requirements for pressure pipelines? 3. If the above scenarios are designed according to pressure pipeline standards, what documents are required for the construction drawing design? 4. Are there any **or industry standards that provide clear definitions for these issues in the relevant regulations? 5. What are your views on this issue, especially from those in design institutes and engineering companies?
The original poster is probably working in the field of pressure vessels, right? What you’re asking about is what needs to be taken into account for pressure pipelines, or rather which pipelines should be designed as such, rather than the distinction between pressure vessels and pressure pipelines!
Reply: 1. The process piping on pressure vessels should be designed as pressure pipelines provided that it meets the requirements for such pipelines. 2. If it is designed as a pressure pipeline, the corresponding level of certification mark for pressure pipeline design should be applied to the construction drawings, similar to the certification mark used for pressure vessel design. 3. Relevant information can be found in documents such as the \"Regulations on the Safety Management and Supervision of Pressure Pipelines\" and the \"Rules for Licensing and Managing Design Units for Pressure Vessels and Pressure Pipelines\"
They shall comply with their respective specifications. Pipelines generally refer to systems for transporting fluids and do not have the functions of equipment, whereas pressure vessels sometimes have transportation capabilities, such as fluid transfer tanks. Regarding the poster’s question, it needs to be analyzed on a case-by-case basis; it definitely cannot be generalized, as that would easily lead to mistakes.
Take a look at GB/T20801-2006 \"Code for Pressure Piping – Industrial Piping\", as well as the \"Rules for Design Approval of Pressure Vessels and Pressure Piping\"; they are available on the forum.
I actually work in process design, but I’ve never been able to figure this out; I’ve seen many piping diagrams before that didn’t require any stamps at all. Are there new regulations regarding this now? What I mean is, if a device is equipped with pipes that are 3 or 4 meters long (a situation that is common in skid-mounted equipment), do these pipes also need to be designed in accordance with pressure pipe standards? This raises the issue of determining where the boundaries between pressure vessels and pressure pipes lie in such devices. It seems I need to take a close look at the relevant regulations and standards now.
The division between equipment and piping is based on the first interface of the equipment as the boundary point; both GB and ASME follow this approach. The equipment portion is designed according to equipment standards, while the piping portion is designed according to piping standards.
Pressure vessels refer to enclosed devices used for holding gases or liquids and capable of withstanding certain pressures. They are defined as fixed or mobile containers in which the maximum operating pressure is greater than or equal to 0.1 MPa (gauge pressure), and the product of pressure and volume is greater than or equal to 2.5 MPa·L, for gases, liquefied gases, and liquids whose maximum operating temperature is greater than or equal to their standard boiling point； Gas cylinders, liquefied gas cylinders, and cylinders for liquids with a standard boiling point of 60°C or lower, whose nominal working pressure at full charge is greater than or equal to 0.2 MPa (gauge pressure), and whose product of pressure and volume is greater than or equal to 1.0 MPa·L ； Oxygen chambers, etc. Pressure pipelines refer to tubular devices that use a certain pressure to transport gases or liquids. They are defined as pipelines for gas, liquefied gas, steam, or liquid media that are flammable, explosive, toxic, corrosive, and have a maximum operating temperature equal to or higher than their standard boiling point, with a maximum operating pressure of 0.1 MPa (gauge pressure), and a nominal diameter of more than 25 mm.
Take a look at GB/T20801-2006 \"Code for Pressure Piping – Industrial Piping\" and \"Rules for the Design Approval of Pressure Vessels and Pressure Piping\"
What are the air pocket and sludge pocket on the separator? Regulatory compliance is not addressed. They are located outside the first flange of the equipment; what standards are used for their manufacture, and are product test plates included (wall thickness of 6 mm, container wall thickness of 12 mm)?
Air tanks and mud tanks are part of the equipment and should be designed and manufactured as pressure vessels.