What are the standard requirements for opening holes in high-pressure pipelines? Comprehensive analysis of the specification system and technical guidelines In the industrial fields such as petrochemicals, natural gas transportation, and power production, high-pressure pipelines serve as crucial lifeline facilities. Their operational safety is directly related to the stability of production and public safety. When it is necessary to perform hole-making operations on high-pressure pipelines - whether it is for adding branches, installing sampling components, or conducting maintenance and renovation - strict adherence to a complete set of technical standards and safety regulations is mandatory. Hole-making on high-pressure pipelines falls under the category of special-level hot work operations, which is highly dangerous. Any operational error could lead to serious consequences such as medium leakage, fire, and explosion. So, what are the specific requirements for high-pressure pipeline hole-making? This article will systematically elaborate on the standard requirements for high-pressure pipeline hole-making from multiple dimensions such as the normative system, technical parameters, safety control, and operation procedures. I. Standard Specifications for Opening Holes in High-Pressure Pipelines 1. Requirements at the national standard level The opening operation of high-pressure pipelines must first comply with the technical standards at the national level. Among them, GB/T 28055 "Technical Specification for Pressure-Resistant Sealing of Steel Pipelines" is the core technical basis for pressure-resistant opening operations, and it sets comprehensive requirements for materials, equipment, processes, and inspections for opening and sealing operations. This standard clearly stipulates: When assembling and welding sealing pipe components under the condition that the steel pipeline contains a conveying medium, relevant regulations should be followed. The GB/T 20801 series of standards for "Pressure Pipeline Specifications - Industrial Pipelines" set out fundamental requirements for the fabrication and installation of pressure pipelines. The fourth part of this series specifically stipulates the technical guidelines for pipeline fabrication and installation. For high-pressure pipelines, the relevant provisions in these standards have direct binding force. 2. Special requirements of industry standards At the level of safe operation, AQ 3060-2025 "Safety Management Specifications for Pressure-Resistant Sealing and Pressure-Resistant Opening Operations" is the latest mandatory industry standard issued in 2025. It was approved by the Ministry of Emergency Management and officially implemented on October 18, 2025. This standard sets systematic requirements for the safety management of pressure-resistant opening operations and is a special specification that must be strictly followed for high-pressure pipeline opening operations. In addition, standards such as SY/T 4059 "Technical Specifications for Pressure Pipe Sealing under Pressure" and others in the petroleum and natural gas industry also provide technical guidance for the opening operations of high-pressure pipelines. 3. Mandatory provisions of safety technical regulations The "Industrial Pipeline Safety Technical Regulations" (TSG 31 - 2025) issued by the State Administration for Market Regulation incorporates high-pressure pipelines into the special safety technical requirements, further clarifying the safety technical guidelines for pipeline opening operations. This regulation integrates the original "Safety Technical Supervision Regulations for Pressure Pipelines - Industrial Pipelines" and other contents, and has improved the design requirements for pipeline components, pipeline systems, and pipeline support components. Supplementary requirements for enterprise standards and operation plans In addition to national and industry standards, for the opening operations of high-pressure pipelines, special operation plans must also be formulated. These plans need to be approved by the enterprise's technical director and filed with the local special equipment regulatory department. The operation unit should select appropriate opening equipment and construction techniques based on the pipeline material, pipe diameter, transported medium, laying process conditions, and operating parameters. II. Applicability Requirements for Opening Holes in High-Pressure Pipelines Pressure level and equipment compatibility requirements High-pressure pipelines generally refer to those with a nominal pressure PN ≥ 10 MPa (approximately 100 kilograms of pressure). For such pipelines, the selection of equipment is the primary standard requirement for pressure-bearing opening operations: Rated pressure requirement for equipment: The rated working pressure of the opening equipment must be 1.2 to 1.5 times higher than the actual operating pressure of the pipeline. For example, if the operating pressure of the pipeline is 15 MPa, the rated pressure of the opening equipment should not be lower than 18 MPa. This safety redundancy design is to ensure that the equipment still has sufficient safety margin even in the case of pressure fluctuations or abnormal operating conditions. Sealing component pressure resistance requirements: The sealing components of the equipment (such as sealing rings, flange gaskets) must be made of materials with high pressure resistance, such as polytetrafluoroethylene, metal-coated gaskets, etc., to prevent leakage of the medium due to sealing failure. Redundant design of balancing device: The high-pressure cutting machine should be equipped with a high-pressure balancing device, and it is advisable to set up two sets of balancing systems. Even if one set of the balancing system fails, it can promptly switch to the other set to ensure the high reliability of the cutting process. 2. The pipe material is compatible with the opening process. High-pressure pipelines are mostly made of high-strength metal materials. Different materials have different requirements for the opening process: Carbon steel and low-alloy steel pipes: Mechanical drilling can be used to create holes. The cutting tools should be made of high-speed steel or hard alloy. The cutting speed needs to be controlled to prevent the inner wall of the pipe from oxidizing due to excessive friction. Stainless steel pipe: It must be opened using a cooling method, and equipped with a cooling fluid circulation system to prevent "work hardening" of the stainless steel during the cutting process, which could lead to rapid wear of the cutting tool or cracking at the pipe edge. Alloy steel and non-ferrous metal pipes: Holes should be drilled using mechanical processing methods. Flame cutting or other similar methods are strictly prohibited to prevent changes in material properties and to ensure that the pipes are not damaged and the hole drilling quality is maintained. Materials prohibited from having holes drilled: For brittle material pipelines (such as high-pressure cast iron pipes) or pipelines with excessive corrosion (where the corrosion depth on the inner wall exceeds 10% of the wall thickness), pressure-holding drilling is prohibited. 3. Control requirements for medium characteristics Pressure-bearing pipeline perforation under pressure is applicable to pipelines with "stable medium and no violent reactions". For special media, there are additional requirements: Flammable and explosive media: Explosion-proof equipment (such as explosion-proof motors and inert gas protection systems) must be equipped. The operation site should be far away from fire sources, and there should be no ignition sources within the operation area. Strongly corrosive media: The opening equipment needs to undergo anti-corrosion treatment (such as surface coating with polytetrafluoroethylene), and the operation time should be controlled within a certain range to prevent the media from corroding the equipment seals for a long time. High-temperature medium: When the medium temperature exceeds 200℃, it is necessary to select equipment that can withstand high temperatures (such as heat-resistant alloy tools, ceramic seals) to prevent the equipment components from deforming and failing due to high temperature. 4. Requirements for the simulation test of the first assignment For construction units and personnel conducting the first opening operation on high-pressure pipelines with different pipe materials, diameters, and operating pressures, simulation tests must be carried out. This is an important step to verify the feasibility of the process and the operational skills of the personnel, and it is also a mandatory requirement stipulated by the standards. III. Technical Requirements for Hole Position and Structure