【Common Issues in Haichuan Pipeline Design】An article explaining the work procedures for pressure pipeline design

Thread Content

The 25th National “Safety Production Month” in 2026: Everyone should talk about safety and know how to handle emergencies; identify and address potential risks and hazards. -------------------------------------------------- During the design, installation, and inspection of pipelines, small issues that have been overlooked or not taken into account are often discovered. These issues are collected and compiled into a series, which is being updated continuously. Everyone is welcome to actively participate in discussions. There is a compilation post on common problems in Haimen Pipeline Design, which is still being updated; feel free to join the discussions: https://bbs.hcbbs.com/thread-5705828-1-1.html ------------------------------------------------------------------ I. Preliminary design phase 1.1 Design preparation 1) Based on the contract documents and the owner’s requirements, clarify the scope of work, tasks, and timeline for this project; estimate the workload, assign personnel, and determine the responsible designers, reviewers, and approvers. 2) The project design manager or the person in charge of professional design for the project may issue supplementary regulations in accordance with the unified technical specifications for preliminary design in this field, to refine the table of pipeline material grades required for the project, and to prepare the relevant standards, specifications, and supporting documents. 1.2 The pipeline stress team prepares a \"List of Pipes for Stress Analysis\" for the pipes that require stress calculation, based on the \"Piping and Instrumentation Diagram\" (PID) provided by the process system team. 1.3 The piping materials department formulates specifications for piping material grades and a piping materials database (including tables of pipe wall thicknesses, as well as tables of installation dimensions and diagrams for valves, fittings, and other piping accessories) based on the \"Piping and Instrumentation Diagrams\" (PID) and piping lists provided by the process systems department. 1.4 It also sets out the requirements regarding the level of detail required in the preliminary design. 1.5 Drawing of the main pipeline layout 1) In the early stages of foundation design, it is necessary to conduct preliminary piping studies on the high-temperature, high-pressure, low-temperature pipelines of large diameter within the facility, as well as on those pipelines that are crucial for determining the layout of equipment and various structures. Sketches of the pipes involved in stress analysis are prepared; once the stress analysis is completed by specialists in this field and approved, the plan for the equipment layout is finalized, followed by a design review. 2) Determine the width, number of layers, and elevation of the pipe gallery, and prepare a layout diagram of the pipes in the gallery. 3) Submit the first civil works requirements. 1.6 Drawing of the sectional study diagram 1) Pipeline studies are conducted for each container equipment (including towers, storage tanks, heat exchangers, and reactors) based on the main pipeline layout diagram. 2) Based on the sectional study diagrams, draw the orientation diagrams of the nozzles of non-standard equipment, and specify the conditions for pre-welding parts at the base of large pipe racks on the equipment, as well as those pre-welding parts required on equipment that needs heat treatment. 3) Submit the first pipeline material summary table (mainly compiling statistics on valves, special fittings, large-diameter pipes, precious metal pipes, and materials ordered from abroad). 4) Provide the second set of civil engineering conditions (including equipment loads) as a modification and supplement to the first set of civil engineering conditions. 5) Propose the requirements for the water supply and drainage discipline. 1.7 Drawing of the basic design pipeline layout: 1) A preliminary pipeline layout is drawn based on the main pipeline route diagram and the detailed study diagrams, and it is provided to the relevant design teams for the basic design work. After being reviewed, verified, supplemented, and modified by these teams, it becomes the final basic design pipeline layout. 2) Adjust the pipe connection positions between the pipe gallery and the equipment. 3) Provide a second summary table of pipeline materials. 4) Adjust the equipment layout from an economic perspective while meeting the piping requirements, to complete the foundation design equipment layout diagram. 1.8 Draw the horizontal and vertical layout diagrams of the equipment. 1.9 Attend the foundation design review meeting: At this meeting, the owner reviews the pipeline layout diagrams for the foundation design, and then the diagrams are updated based on the feedback received; the revised versions serve as the basis for the detailed engineering design. 1.10 Relevant regulations required for preparing the detailed design, such as unified regulations for pipeline material design, regulations for pipeline material grades, regulations for pipeline material coding, regulations for valve coding, branch pipe connection tables, regulations for insulation design of equipment and pipelines, regulations for painting of equipment and pipelines, regulations for steam tracing (or electric tracing) design, regulations for jacketed tube design, regulations for utility pipeline design, regulations for pipeline support and hanger design, etc. II. Detailed (construction drawing) design phase 2.1 Design preparation 1) Identify the responsible professional designer, reviewers, and estimate the design workload and required hours. Prepare a design schedule. 2) Modify the equipment plan and elevation layout drawings based on the preliminary design review comments, and provide them to the relevant specialties. 3) Verify and refine the pipeline grade table used in the construction drawing phase. 4) Divide the entire installation into several zones according to the equipment layout plan and assign zone numbers to them; designate the designers and reviewers for each zone; allocate tasks related to piping and other specialties; and agree on the installation locations for underground pipes, fire protection pipelines, cables, instrument trays, etc. 5) In accordance with the design requirements at the construction drawing stage, the project design manager or the professional design supervisor shall refine the unified design technical regulations based on the design characteristics of this project. 2.2 Construction version pipeline layout diagram: 1) Based on the foundation design equipment layout diagram, equipment assembly drawings, as well as the requirements specified by various disciplines (such as information regarding platform ladders, power distribution, lighting, pipe rack loads, openings, embedded components, equipment foundations, sewage drains, sewage/discharge points, trench dimensions and locations, heating and ventilation, etc.), the pipeline layout diagram is further refined to produce the construction version pipeline layout diagram. 2) Complete the orientation diagram of the no-standard equipment outlets. 3) The piping materials department prepares the drawings of special fitting requirements based on those submitted by the process system department and the piping department. Draw manufacturing drawings for special pipe fittings. 4) The pipeline stress team is required to carry out verification calculations for pipeline branch compensations. 5) Draw the pipe rack layout diagrams and prepare pipe rack tables; the pipeline stress team is responsible for drawing diagrams of special pipe racks, compiling a list of all materials required for the pipe racks as well as spring supports and hangers, and preparing a material table for the pipe racks. 2.3 The third pipeline material summary table is prepared at the end of the detailed design; the pipeline materials team conducts a third compilation of pipeline materials based on the material lists generated by computer-aided piping design. This material tally represents the final summary of all materials used by the piping team, including auxiliary materials. Now, 3D models are used to create various material tables quickly and directly. 2.4 Preparation of the drawing catalog and detailed design specifications 2.5 Organization, review, coordination, and signing of design documents. The above steps are applicable in cases where hand-drawn engineering drawings are used and a significant amount of manual labor is involved. Now it’s all about digital delivery and digital models; many steps can be completed in advance or directly at various stages. Model review nodes 30, 60, and 90 have all basically completed their internal verification.