Comprehensive Analysis of the Entire Process of Pressure-Resistant Hole Opening Maintenance: Safe and Efficient Maintenance and Repair Technology Without Production InterruptionPerforming an "operation" directly on a high-pressure flammable pipeline while ensuring that the medium continues to flow normally, with zero sparks and leaks, this technique, known as "industrial heart bypass surgery", is quietly safeguarding every beat of the city's vital system. In the dead of night at the Northwest Oilfield, the lights of the 4-2 Branch Transfer Station in the Shunbei Area 2 illuminated the desert night sky. Bai Honghai and his team were making the final preparations for an upcoming pressure-bearing perforation operation. They were like surgeons performing an operation on the "heart" of oil and gas transportation, but the object of their surgery - that high-pressure and high-sulfur pipeline - could not have a moment of rest. This is a key challenge in the field of modern industrial emergency repairs: How to safely and accurately carry out hole-making, modification or repair work while the pipeline is under pressure and the medium is flowing, to ensure the continuous operation of the entire production system? 01 Technical Principles and Core Values Pressure-tight hole opening, also known as "Hot Tapping", is a maintenance and repair technique that emerged in the 1960s. This technology enables the direct manufacturing of interfaces, the addition of branches, or the carrying out of maintenance operations on in-service pipelines transporting water, crude oil, refined oil, chemical media, or natural gas, all while under pressure. The entire process does not require downtime, venting, or the use of open flames. The core working principle is to use a dedicated opening sealing device to implement "double sealing and double blocking" at both ends of the pipe section that needs construction, thereby cutting off the flow of the medium in that section. At the same time, by using the temporarily set up bypass pipelines, the medium in the pipeline can be redirected, thus maintaining the continuous flow of the entire pipeline system. Imaginatively speaking, it's like building temporary auxiliary roads for the expressway, so as to carry out the construction and replacement of the main road bridges without interrupting the main traffic flow. The value of this technology is manifested in multiple aspects: safety, environmental protection, economy, and efficiency. It has completely solved the problems that traditional maintenance methods must face, such as pipeline shutdown, pressure reduction, and venting. It avoids huge economic losses and energy waste caused by production suspension, and also eliminates many risks in the operation process. 02 Preliminary Evaluation and Precise Preparation Carrying out pressure-opening operations is by no means a simple on-site task. Its success is highly dependent on meticulous pre-planning and preparation. As this operation itself falls under the category of high-risk pressure and hot work special operations, any negligence could lead to serious consequences. Before starting the project, a dedicated project team must be established to conduct a rigorous feasibility analysis and hazard assessment of the construction plan. The key assessment contents include: · Pipeline status: Accurately measure and verify the material, diameter, wall thickness, operating pressure and medium characteristics (such as whether it is flammable, explosive, toxic, or contains sulfur) of the pipeline. · Environmental Analysis: Assess whether the work site is restricted and whether there are any fire sources or sensitive facilities in the surrounding environment. · Equipment matching: Based on the assessment results, select the drilling machine, cutting tools and seals that are fully compatible in terms of model and pressure rating. The core of construction preparation is the positioning of equipment and materials. The main equipment usually includes the hole-opening machine, the plug-in device and the lower plug-in device. They share a dedicated frame composed of sector-shaped clamp valves, connectors, etc. This rack is typically made of anodized aluminum alloy, which possesses the advantages of corrosion resistance and light weight. All equipment, pipe fittings, valves and sealing materials must undergo strict inspection and pressure testing to ensure flawless performance. 03 Detailed Explanation of Standardized Work Procedures A complete and standard pressure-bearing hole-opening maintenance operation follows a series of closely interlinked procedures. The main process will be divided into four stages for a clearer understanding. Phase One: Install the connection base Firstly, on the pipeline at the predetermined opening position, a "short section" with a flange is welded. The welding process itself is extremely risky and often requires protective measures such as covering the pipeline surface with wet fireproof blankets. · Operation: Weld the short section with flange. · Objective/Key Point: Establish operation connection points and perform welding with professional preheating and process requirements. · Risk control: Throughout the process, strict monitoring is carried out to prevent the pipe wall from being pierced. Phase Two: Establish a closed working chamber On the welded short section flange, install a full-diameter gate valve. After the valve is opened, attach the opening machine to the valve through the dedicated connector. · Operation: Install the gate valve and the hole drilling machine. · Objective/Key Point: Valves serve as a crucial safety barrier, and the connection must be absolutely sealed. · Risk Control: Conduct airtightness tests on all connection points. Phase Three: Performing Pressure-Resistant Cutting Start the hole-making machine. Its drill rod drives the cylindrical cutter to slowly penetrate the pipe wall. · Operation: Start the drilling machine to perform the cutting process. · Objective/Key Point: Cut off a complete curved tube section (pulverized material). · Risk control: The cutting speed is slow and steady, and the pressure and torque are monitored in real time. Phase Four: Conclusion and Recovery After the cutting process is completed, the cutting tool returns the material cake to the closed opening machine's chip storage compartment.