【Serial】Design Story-46: Starting the piping work

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(46) The day after the exam was Sunday, and Ye Wenhui, Huang Lei, and Ai Guoxin slept until past 10 a.m. still unable to shake off the fatigue from the previous day. After getting up, the three of them played Dota together until 12 p.m., before going to have their first meal of the day. While eating, Huang Lei said to Ye Wenhui, “Get ready; once you start working on Monday, President Liu will definitely come to see you.” ” “How do you know? What do you want from me? ” ““It’s fine, welcome to the team of those who suffer, haha…” Hearing this, Ye Wenhui understood that it was just about piping work – was it really that troublesome? As expected, at 10 a.m. on Monday, Liu Shuang called Ye Wenhui to his office. After asking about the exam results, Liu Shuang said, \"Go and see Director Zhang after you return; you should also work on some piping projects to gain some experience.\" ”From the tone, there’s no room for negotiation at all. Ye Wenhui went to find Zhang Qiyun, who said, “Go and find Engineer Huang in a bit; ask her to send you the blueprints.” ”After going around in circles, Ye Wenhui returned to his work station to find Sister Huang who was nearby. Sister Huang seemed to have already known that Ye Wenhui would be in charge of the piping work. As soon as she heard that Ye Wenhui had finished, she said, “Okay, I’ll send you the terms; please receive them.” ” What Sister Huang sent to Ye Wenhui was a compressed file; after decompressing it, there were several drawings in DWG format as well as a few Word files. These were the conditions mentioned by Sister Meng. Ye Wenhui took a look; these documents included the general layout plan, piping and instrumentation diagrams, equipment layout plans, lists of equipment, pipeline data sheets, as well as many drawings of the equipment’s appearance. The few files in Word format contained process descriptions and the Material Safety Data Sheets (MSDS) for the substances involved in the process. Sister Meng said, “First, take a look at these materials to get an understanding of this project. The key is to examine the piping and instrumentation diagrams in conjunction with the process descriptions. Once you’re familiar with the process, then look at the equipment layout diagrams based on the list of equipment. If you need to know more about the detailed structure of a particular piece of equipment, then check its corresponding schematic diagram. Feel free to ask me if there’s anything you don’t understand.” ” “Okay, thank you, Sister Meng. May I ask first, what do I need to do after reviewing these drawings? ” Sister Meng said, “Once you’re familiar with it, it’s time to handle the piping work. The main tasks are choosing the pipe materials, drawing up pipe layout diagrams, and finally keeping track of the materials used. First, get to know the manufacturing process; once you’re familiar with it, I’ll tell you what to do. Hurry up and take a look – this project is quite urgent.” ” “Okay, Sister Meng, go ahead with your work. I understand. ” Ye Wenhui carefully examined the materials given to him by Sister Meng. It was a mixed solvent recovery system with an annual processing capacity of 50,000 tons; the substances recovered included ethanol, propanol, butyraldehyde, butanol, and others. The process system mainly consists of 8 distillation kettles and 4 rectification towers; no chemical reactions are involved, and the process is not complex, yet Ye Wenhui still spent a whole day to understand it. Sister Meng drew a total of 10 A1-sized P&ID diagrams as well as 2 utility system diagrams (UIDs). There were a very large number of pipelines, with over a hundred of them in total. Compared to the gas stations and CNG stations that Ye Wenhui has worked on before, this project is already quite complex. After understanding the process, Ye Wenhui spent another half day learning about the equipment layout. After feeling that he had seen almost everything, he turned to Sister Meng and said, “Sister Meng, I’ve finished watching. What should we do next?” ” Sister Meng was busy working on the process design for another project; after hearing Ye Wenhui’s words, she asked, “Have you done piping work before?” ” Ye Wenhui said shyly, “I’ve never worked on something this complex. Back before, when I was working on gas stations and CNG stations, I handled some simple piping work.” ” “Hehe… Next is the piping process. In fact, regardless of the size of the project, the basic principles remain the same: first, choose the pipe material, then determine the route of the pipes, and finally count the amount of pipe material needed – the only difference being the number of pipes involved. What you need to do next is to create a pipeline grade index table, a pipeline material grade table, a pipeline wall thickness table, and a pipeline branch table, based on the materials involved in the manufacturing process. These tables are available on our internal network; find them and use them as a guide for creating the necessary tables. ” It was the first time for Ye Wenhui to hear about these tables; he had no idea what was contained in them, let alone how to use them. He asked Sister Meng anxiously, \"What are these tables used for?\" ” Sister Meng said, “Let me explain first: the purpose of these tables is to determine the pressure rating, material, specifications of all pipes and pipe components in a project, as well as the methods of connecting pipes of different sizes. Although they seem to contain little information, they are very important for the entire project.” The pipeline grade index table specifies the basic materials for pipes of each grade in a project, the media they can handle, the temperature ranges in which they can be used, the pressure ratings of the flanges, as well as the corrosion allowance. This table can be regarded as a comprehensive guide for pipeline materials; all other tables related to pipeline materials must comply with the provisions of this index table. By the way, do you know how pipeline grades are indicated? ” Having worked on two simple projects, Ye Wenhui was still aware of the ways in which pipe grades are denoted. However, those two projects were too simple, and he hadn’t created any index table for pipe grades during them. Upon hearing Sister Meng’s question, Ye Wenhui replied immediately, “I know; it’s things like L1B, M1B, right?” ” “Yes, the first letter represents the pressure rating, the numbers represent the material code, and the second letter indicates the material corresponding to that code. There are pre-made tables available on the internal network; you can check them there later. For this project, there are few levels of pipeline classification, and these are already indicated on the flow chart. When creating the table, you need to match the pipeline levels shown on the flow chart to ensure consistency. ” “Okay, I’ll look for it in a moment. ” “Speaking of the contents of the other tables, the pipeline material grade table provides detailed specifications regarding the materials used for all pipes, as well as pipe fittings such as elbows, tees, reducers, valves, and flanges, within a given pipeline grade. It specifies the standards applied, size ranges, pressure grades, models, and more. Therefore, the pipeline material grade table must be prepared corresponding to each pipeline grade, with one table for each grade. A pipe wall thickness table is a table that specifies the wall thicknesses of pipes of all diameters used in a project, based on the pipe grade. The pipe branching table specifies the connection methods for pipes of different diameters based on specific pipe grades. A pipeline branch table is not necessarily created for each pipeline grade; if the same connection method is used, different pipeline grades can be listed in one table. These tables are also available in the Unified Regulations. ” At this point, Ye Wenhui seemed to recall something. He said, “I remember now; I think I’ve seen it before.” ”When he looked at 20519 himself, he did indeed see those tables that Sister Meng had mentioned, but he didn’t pay much attention to them at the time. Sister Meng said, “First, try to find these tables on the internal network and get familiar with them. When it’s time to choose the pipes, come to see me and I’ll tell you how to make the choice.” . ” “Okay, thank you so much, Sister Meng, hehe……”