How to perform pressure repair for pipe openings: A comprehensive analysis of the non-stop operation emergency repair technology During the operation of pipeline systems such as those for oil, natural gas, chemicals, and urban water supply and heating, pipeline leakage caused by corrosion, external force damage, material defects, etc. is an inevitable problem that cannot be completely avoided. Traditional maintenance methods require pipeline shutdown, emptying, and replacement, which not only cause huge economic losses but also may affect the normal production and life of downstream users. cdimensions such as technical principles, operation procedures, equipment configuration, key control points, and safety measures how the pipeline opening equipment conducts pressure-limited leak repair operations. I. Overview of Pressure-Resistant Leak Repair Technology Technical Definition and Core Value Pressure sealing for leaks, as the name suggests, refers to a technology that involves using specialized equipment and processes to seal and repair leakage points when the internal medium of the pipeline is under pressure. The pipeline opening equipment plays a crucial role in this process - it can precisely make openings on pressurized pipelines, providing conditions for subsequent sealing, welding, or installation of leak sealing devices. Compared with traditional shutdown maintenance, the core value of pressure-based leak repair lies in: avoiding production disruptions and economic losses caused by shutdowns; eliminating the waste of media and environmental pollution risks during the purging and replacement processes; reducing safety hazards associated with hot work operations; significantly shortening the repair time and ensuring the continuous and stable operation of the pipeline network. 2. Main methods of pressure-sealing leakage repair Pipeline opening equipment is used for pressure-limited leak repair, and there are mainly the following several technical approaches: Opening and Sealing Method: Install opening valves on both sides of the leakage point. Use the opening equipment to make holes in the pipeline, insert the sealing device to establish a temporary seal, isolate the leakage section, and then carry out repair. This is the most commonly used and reliable method. Cylinder-type leak sealing method: For local perforations or cracks, a hole can be drilled above the leakage point using a drilling device, and then a sealing component (such as a sealing plug or sealing cylinder) can be inserted through this hole to achieve point sealing. Freeze isolation method: In combination with the opening equipment, ice plugs are formed on both sides of the leakage point through the freezing process to isolate the leakage section. Then, the opening and repair can be carried out. Fixture injection method: Install a special fixture at the leakage point. Use the opening equipment to drill injection holes on the fixture, and inject the sealing adhesive to form a seal. II. Core Technical Principles of Pressure-Resistant Leak Repair Pressure balance principle The core technical challenge of pressure sealing lies in how to safely make holes and seal them in a high-pressure environment. The key technology is the pressure balance principle - through devices such as clamp valves and hole-making machines, the pressure in the hole-making area is maintained in balance with the external environment throughout the hole-making process, preventing the leakage of the medium. Specifically, after welding the flange sections or installing the clamp valves on the pipeline, the drilling machine is connected to them. The drilling machine is equipped with a balance valve and a pressure relief valve. When the drilling bit penetrates the pipe wall, the cavity inside the drilling machine will instantly be filled with the pipeline medium. The balance valve ensures that the cavity of the drilling machine is at the same pressure as the pipeline, and then the pressure is released through the pressure relief valve. After confirming there is no leakage, the next step can be carried out. This series of operations ensures the safety and controllability of the drilling process. 2. Principle of Mechanical Sealing The sealing elements used in pressure sealing operations, such as sealing caps and plugs, mainly rely on mechanical compression and elastic compensation for their sealing principle. The sealing components of the sealing caps are typically made of oil-resistant, temperature-resistant, and corrosion-resistant rubber or polytetrafluoroethylene materials. They are mechanically compressed onto the inner wall of the pipeline to form a reliable seal. For the cylindrical blocking device, the sealing discs at both ends are pressed against the inner wall of the pipeline under the action of axial force, achieving bidirectional sealing. For the folding blocking device, the blocking head enters the pipeline and then unfolds, with the sealing elements fitting against the inner wall of the pipeline, maintaining the sealing force through mechanical locking or hydraulic means. 3. Principles of Welding and Structural Reinforcement When performing welding for leak repair under pressure, issues such as weld burn-through and hydrogen-induced cracks during pressure welding need to be addressed. The welding operations in pressure leak repair usually employ the following techniques: controlling the welding current and heat input to avoid local overheating; using low-hydrogen electrodes to prevent hydrogen-induced cracks; implanting leak-blocking components at the leakage point to reduce the leakage volume, and then performing welding coverage; for larger leaks, installing reinforcement plates or sleeves first, and then conducting welding. III. Complete Operating Procedure for Pressure-Resistant Leak Repair On-site investigation and scheme design The first step in any pressure repair operation is the on-site investigation. Technicians need to have a detailed understanding of the location of the leak point, the form of the leak (puncture, crack, weld defect, etc.), the pipe specifications (material, outer diameter, wall thickness), operating parameters (medium, pressure, temperature), and the on-site environment (above ground, underground, confined space, etc.). Based on the investigation results, a specific repair plan is designed, including selecting the repair method, determining the location and size of the opening, choosing the equipment model, formulating the operation steps and safety measures. 2. Homework Preparation Equipment Preparation: Select the appropriate equipment such as hole-making machines, clamping valves, sealing devices, and leak-filling components based on the plan. Inspect the equipment to ensure that all components are in good condition, the seals are not aged, and the hydraulic system is functioning properly. Pipeline treatment: Clean the anti-corrosion coating and debris around the leakage point, exposing the metal surface. For the parts that require welding of flange sections, perform grinding treatment. Safety protection: Establish an operation warning zone, equip with fire-fighting equipment, and ensure that the workers wear protective gear. For flammable and explosive substances, take explosion-proof measures and use explosion-proof tools and equipment. Temporary measures: In cases where the leakage is significant, temporary drainage or pressure reduction measures can be taken to reduce the operational risks.