Maximum allowable pressure of pipeline

The maximum allowable operating pressure of the pipeline must not exceed the design pressure (except for hydrostatic testing, etc.).

The maximum allowable operating pressure is the highest pressure that a container is permitted to withstand, as determined based on its effective wall thickness; it is generally higher than the design pressure. The design pressure is the pressure used at the corresponding design temperature to determine the calculated wall thickness of the container as well as the dimensions of other components. It can be set slightly higher than or equal to the maximum operating pressure. The maximum operating pressure is the highest pressure that may occur during use, and it must not exceed the design pressure

The “Chemical Process Piping Handbook” should have regulations on this.

Rules for Licensing the Installation of Pressure Pipelines Chapter 1 General Provisions Article 1 These rules are formulated in order to ensure proper licensing of entities engaged in the installation of pressure pipelines (hereinafter referred to as installation entities), in accordance with the Provisions on the Safety Supervision of Special Equipment (hereinafter referred to as the Provisions) and the Decision of the State Council on Granting Administrative Licenses for Administrative Approval Items That Must Be Retained (State Council Order No. 412) (hereinafter referred to as the Decision). Article 2: Any pressure pipeline installation unit that operates within the territory of the People’s Republic of China to install pressure pipelines falling within the scope of application of the Regulations and the Decisions must have an installation license that complies with the provisions of these rules. Article 3: The licensing for the installation of pressure pipelines (including renovation and maintenance) shall determine the scope of licensing based on the category and grade of the pressure pipelines; the specific classification is provided in Appendix A. Article 4: The General Administration of Quality Supervision, Inspection and Quarantine (hereinafter referred to as the **GAQSIQ**) shall exercise unified supervision over the licensing process for pressure pipeline installation. **The General Administration of Quality Supervision, Inspection and Quarantine is responsible for approving installation permits for pressure pipelines of category GA and grade GC1, while provincial quality and technical supervision departments are responsible for approving installation permits for pressure pipelines of other grades within their respective jurisdictions. Article 5: The validity period of the installation license is 4 years. Entities that have obtained the \"License for the Installation, Modification, and Maintenance of Special Equipment (Pressure Pipelines)\\" shall use the \"license mark\" and the license number on the pressure pipeline projects they install (for the format, see Annex B). Article 6: The institutions responsible for the assessment and evaluation of permits for the installation of pressure pipelines (hereinafter referred to as assessment and evaluation institutions) shall be announced by the **General Administration of Quality Supervision, Inspection and Quarantine. Chapter 2 Basic Conditions and Requirements for Installation Licenses Article 7 The installation entity shall possess the legal qualifications and be registered with the administrative department for industry and commerce. The registration certificate should contain information consistent with the business being carried out. Article 8: The installation unit shall carry out the installation of pressure pipelines in accordance with China’s safety technical specifications and the corresponding design, installation, and completion inspection standards. The installation unit shall ensure that all safety performance aspects of the pressure pipelines it installs meet the requirements of the relevant technical specifications for pressure pipeline safety. The installation unit carrying out the initial certification and additional (or upgraded) installations must prove through a trial installation that it has the capability to install pressure pipelines that meet the requirements. Article 9: The installation unit shall possess the capabilities required for the installation of pressure pipelines, and its resources such as personnel, facilities, and inspection methods shall meet the following basic requirements: (1) It shall have management personnel, professional technical personnel, inspection personnel, and skilled workers suitable for the installation work ； (II) Have production conditions suitable for installation, including office facilities, installation equipment and process machinery, factory premises for testing, and storage areas for raw materials and prefabricated products ； (III) Detection methods suitable for installation, including testing instruments, non-destructive testing equipment, physical and chemical testing equipment, measuring instruments, and testing conditions ； (IV) A sound quality management system ； (5) Possess the capability to carry out the main installation and production processes as well as to conduct final inspections. Specific resource details are provided in Appendix C. Article 10 The installation unit is responsible to the user for the quality of the raw materials, components, and pressure pipeline elements purchased by it. In pressure pipeline projects, for raw materials, components, and pressure pipeline elements that are purchased by the installation party or by the user themselves and fall under the scope of the \"Rules for Licensing the Manufacture of Pressure Pipeline Components\", the manufacturing units must possess the necessary licensing to produce such components. Non-destructive testing agencies must have the qualification approved by the General Administration of Quality Supervision, Inspection and Quarantine, and must be capable of carrying out the relevant, approved non-destructive testing procedures. Article 11: The installation unit shall, in accordance with the requirements of the \"Basic Requirements for Quality Assurance Systems for the Manufacturing, Installation, Modification, and Maintenance of Special Equipment\", and taking into account its own specific circumstances, establish, implement, maintain, and continuously improve a quality assurance system related to the licensed activities, and shall also prepare documents related to this quality assurance system. Article 12: The installation unit shall carry out the notification procedures prior to commencement of installation work (including trial installation). For long-distance pipelines that span provinces, such procedures must be carried out with the **General Administration for Quality Supervision, Inspection and Quarantine; for other pressure pipelines, the procedures shall be carried out with the local quality and technical supervision departments, so as to undergo supervision and inspection. Chapter 3 Installation Permit Procedure Article 13 The installation permit procedure for pressure pipelines includes application, acceptance, trial installation, evaluation and assessment, approval, and issuance of certificates. Article 14: The installation unit shall submit an application for installation permission to the approval authority, along with the following application documents: (1) Application form for permission to install, modify, or repair special equipment (in four copies, along with an electronic version) ； (II) Company Overview ； (III) Business license (copy) ； (IV) Organization Code Certificate (copy) ； (5) Certifications or other qualification certificates obtained (copies) ； (VI) Quality Assurance Manual ； (7) Other materials that require additional explanation. Article 15 The approval authority shall examine the application materials submitted by the installation unit. A decision on whether to accept the application will be made within 5 working days of receiving the application materials. Article 16: For installation units that meet the application requirements, the approval authority shall sign an acceptance opinion on the application form and return two copies of the form to the installation unit (one of which is to be submitted to the appraisal and evaluation agency after it is appointed), one copy is to be sent to the special equipment safety supervision agency of the quality supervision department at the next lower level of the approval authority, and one copy is to be kept by the approval authority for archiving. Applications from installation units that fall under any of the following circumstances shall not be accepted. In cases where the application is not accepted, the approving authority shall sign a decision indicating non-acceptance on the application form and issue a decision not to accept it. (1) The application materials do not meet the requirements specified in Chapter 2 ； (II) Concealing relevant information or providing false application materials ； (III) Subject to legal actions or other judicial disputes that have an adverse effect on obtaining the ‘License for the Installation, Modification, and Repair of Special Equipment’, or currently under relevant judicial restrictions and penalties. If the installation unit conceals relevant information or submits false application documents, it shall not apply again within 1 year. If the licensing process cannot be completed within 18 months due to reasons on the part of the installing party, such party shall submit a new application based on any changes in its circumstances. Article 17 The following entities shall not apply for a pressure pipeline installation permit: (1) societies, associations, professional consulting firms, and other such entities ； (II) Inspection and testing agencies engaged in the manufacturing of pressure pipeline components and the supervision and inspection of pressure pipeline installation ； (III) Certification and evaluation agencies for pressure pipeline design, component manufacturing, and installation licensing, as well as relevant type testing agencies. Article 18: The installation unit whose application for permission has been accepted shall conduct a trial installation at the level for which the application was accepted (only one pipeline trial installation is permitted per level). Article 19: Where trial installation requires supervision and inspection in accordance with regulations, such supervision and inspection must be carried out in line with the requirements set forth therefor. If installation supervision and inspection are not carried out, an invited appraisal and evaluation agency can conduct an evaluation of the installation quality, followed by an appraisal and evaluation once the evaluation is completed. The invited appraisal and evaluation agency shall arrange the appraisal and evaluation work in accordance with the requirements of the \"Rules for the Management and Supervision of Appraisal and Evaluation for Administrative Licenses of Special Equipment\", and send a copy of the \"Notice of Appraisal and Evaluation for Special Equipment\" to the quality and technical supervision department responsible for license approval. Article 20 The installation quality assessment mainly includes the following aspects: (1) Verifying whether the actual conditions of the installation unit correspond to the information provided in the application ； (II) Check whether the resource capabilities of the installation unit and other necessary conditions meet the requirements of the applied level, and whether the inspection and testing methods are appropriate for the applied installation level ； (III) Conduct installation quality evaluations for the trial installation projects at various levels applied for by the installation unit. Article 21: Upon completion of the installation quality assessment, the appraisal and evaluation agency shall issue a separate installation quality assessment report for each project within 20 working days. The installation quality review report is generally prepared in three copies. One copy is kept by the installation unit, one is archived by the appraisal and evaluation agency, and one is used to handle relevant permits. If the actual conditions of the installation unit under evaluation do not match the information provided in the application documents, or if the quality of the trial installation is unsatisfactory, the evaluation agency shall suspend the evaluation process and report to the approving authority within 15 working days. Article 22: After the installation quality review is completed, the appraisal and evaluation agency shall, in accordance with the requirements of the \"Detailed Rules for Appraisal and Evaluation of Installation, Modification, and Maintenance of Special Equipment\", organize an appraisal and evaluation of the installation unit, which shall include the following aspects: (1) Verifying whether the installation unit meets the requirements set out in Articles 7, 8, 9, 10, and 11 of these rules ； (II) Verify the installation quality assessment report by examining the technical documents and work records related to the trial installation, in order to confirm whether the trial installation was carried out in accordance with the quality assurance system ； (III) Confirm the usage method of the permission mark ； (IV) Determine the categories, levels, and scope of installation permits. The appraisal and evaluation agency shall issue an appraisal and evaluation report within 20 working days after the completion of the appraisal and evaluation work. In cases where the installation unit is required to make corrections, a certification and evaluation report shall be issued within 10 working days after the completion of the corrections is confirmed. Article 23: Upon receiving the appraisal and evaluation report, the approval authority shall complete the review, approval, and issuance of the license within 30 working days. Article 24: Installation units that have obtained an installation license shall go through the procedures for licensing changes when there are alterations to their unit name, address, ownership rights, etc. When the legal representative is changed (without any change in ownership) or when the technical supervisor is replaced, it is necessary to inform the approval authority and the local quality and technology supervision department in writing within 15 days of the date of the change. Article 25: An installation unit that has obtained an installation license and needs to increase the category or level of its installation license within the validity period of such license shall go through the procedures for applying for an additional installation permit in accordance with the requirements of these rules. Article 26 Installation units that have obtained an installation license shall comply with the following provisions in their production and business operations: (1) They shall not violate the requirements of relevant laws, regulations, rules, and safety technical standards ； (II) The “License for the Installation, Modification, and Maintenance of Special Equipment” shall not be altered, forged, transferred, or sold ； (III) Pipes shall not be installed beyond the permitted scope, nor shall the permit markings be used beyond the permitted limits ； (IV) It is prohibited to illegally provide (sell) quality certificates or approval documents ； (5) It is not permitted to allow installation units without proper licenses to carry out pipeline installation under one’s name ； (VI) It is prohibited to conceal relevant information from users or provide false documents and materials. Article 27: Installation units that have obtained an installation license and wish to continue carrying out installation work after the expiration of its validity period shall submit an application to the approval authority six months prior to the expiration date of the license. If the certification is not renewed after its expiration date, the original license automatically becomes invalid. Article 28: When submitting an application for certificate renewal, the installation unit shall have corresponding installation experience. In addition to the documents specified in Article 14, the installation unit shall also submit the following documents: (1) Information on the handling of installation quality incidents ； (II) Copy of the original “License for Installation, Modification, and Maintenance of Special Equipment”. Article 29 The procedures for reissuing the certificate shall be in accordance with the provisions of Articles 14 to 16, and Articles 22 and 23. In addition to the contents specified in Chapter 2, the certification renewal review shall also include the following: (1) The implementation of laws, regulations, and relevant standards related to pressure pipelines ； (II) Situation regarding the quality supervision and inspection of all installation projects ； (III) Whether there are instances of installation beyond the permitted scope, and whether there are cases of unlicensed installation units operating under false pretenses ； (IV) Implementation of the quality assurance system ； (5) Handling of major quality incidents related to the licensed projects and user feedback ； (VI) Changes in resource conditions ； (7) Conduct on-site spot checks on the installation quality of pressure pipelines. Chapter IV Supplementary Provisions Article 30 These rules shall be interpreted by the **General Administration of Quality Supervision, Inspection and Quarantine. Article 31 These rules shall come into force as of the date of 200 year month day. The \"Implementation Rules for the Accreditation of Pressure Pipeline Installation Units\" issued by the former **Quality and Technical Supervision Bureau on June 8, 2006, were simultaneously repealed.

If you want to increase the inlet pressure of the compressor, it’s best not to do so； The design suction pressure of a compressor is the suction pressure during operation; there is no such thing as multiplying it by a coefficient ； Slightly increasing the pressure at the compressor inlet should not pose any problem in terms of the stress on the compressor itself and its pipelines. The key issue is that the compressor’s load will increase; it’s important to determine whether this increased load falls within the machine’s capacity limits. If an increase in pressure is necessary, it’s advisable to do so in small steps, with an increase of no more than 10% likely to be sufficient ； To increase the inlet pressure of the compressor, you also need to consider the pressure tolerance of the equipment in the preceding process stages; it must not exceed the maximum operating pressure specified in the equipment’s specifications. Otherwise, although it may not necessarily cause problems, no one can guarantee that nothing will go wrong. I have seen L3.3 compressors from many manufacturers (including ours), whose designed inlet pressure is 0.025 Mpa (gauge), but the actual inlet pressure is usually around 0.045 Mpa, and they still function properly.