What material should be used for 5.0MPa low-temperature liquid oxygen pipelines?

There is no temperature specified; refer to the design specifications for oxygen stations

Friends have asked about this kind of question before. I’ve compiled the useful information for you to take a look at. I. Liquid oxygen is classified as a Class B fire hazard material. According to the classification of pressure pipeline design categories and levels specified in the \"Rules for Licensing and Management of Units Qualified to Design Pressure Vessels and Pressure Pipelines\", and considering the design pressure of 40 bar under the operating conditions you provided, it falls under GC1(2). Second, the \"Regulations on the Safety Management and Supervision of Pressure Pipelines\" have no inherent connection with the classification and grading of pressure pipelines; rather, it provides a definition of pressure pipelines and sets out rules for their management and supervision. The classification of pressure pipeline categories and grades shall be in accordance with the provisions of the \"Rules for the Qualification Licensing and Management of Design Units for Pressure Vessels and Pressure Pipelines\". For your reference. III. Low-temperature pipelines are generally made of seamless steel pipes made of stainless steel 304. For some special media, such as liquid oxygen, it is necessary to control the carbon content in the pipes; grades 304L or 316 are preferred. In pipeline design, attention must first be paid to the vaporization of low-temperature liquids. Whether it is an insulated pipe or a vacuum pipe, gasification-induced pressure increase to varying degrees will occur; therefore, a safety valve must be considered between the two stop valves. Otherwise, the pipeline pressure could increase excessively at any time, which in the worst case could lead to a pressure explosion. IV. Next, the issue of cold shrinkage needs to be considered.

Is it feasible to use aluminum alloy material specifically?

I’m not quite sure about this. One netizen replied like this: Stainless steel is used for large-diameter pipes with low flow rates, while Monel is used for small-diameter pipes with high flow rates.

The experts upstairs said to check the flow rate and design specifications; take a closer look, and then it should be clear. Estimated 304, 304L ； 316 and 316L can be used

For oxygen, only the flow rate matters; for liquid oxygen, it should not exceed 1 m/s, and stainless steel should be used

Our material is GC1, austenitic stainless steel.

Austenitic stainless steel is used for liquid oxygen pipelines; in our facility, the pipelines for liquid oxygen are basically made of 304 material, and that’s perfectly fine. Aluminum pipes can withstand low temperatures of -183°C, but they have low strength and are hardly used