Analysis of the Complete Process of Pressure-Resistant Hole Opening Maintenance: Non-stop Pipeline Operation "Minimally Invasive Surgery" in Modern IndustryAt 3 a.m., the monitoring screen of the dispatch center of a large oil refinery suddenly displayed an alarm - there was an abnormal fluctuation in pressure on a key pipeline supplying raw materials to the catalytic unit. The initial judgment was that it was due to local corrosion and thinning. According to the traditional plan, the entire plant would need to urgently reduce production and shut down, resulting in a daily economic loss of over one million yuan. However, the repair team initiated a special plan and completed the local repair in less than one day while keeping the pipeline operating at full pressure. The entire process did not affect the production of any downstream units. This is the practical application scenario of the pressure-bearing hole-opening maintenance technology. This technology, known as the "minimally invasive surgery for industrial pipelines", is completely transforming the traditional operation mode of pipeline maintenance and has become a key technical means for ensuring the continuous safe production of modern industries. Part One: Overview and Basic Principles of Pressure-Resistant Hole Opening Technology What is pressure-bearing opening repair? Pressure-bearing opening repair is a specialized engineering technology that enables the modification, restoration or connection of pipelines by creating interfaces on the pipeline and installing temporary or permanent devices while the pipeline remains under normal operating pressure and the medium continues to flow. Compared with the conventional maintenance methods, the pressure-bearing hole opening technology has the following revolutionary advantages: 1. Production continuity guarantee: Completely avoid production downtime losses. This is particularly important for continuous production enterprises. 2. Significantly reduced safety risks: Avoided high-risk operations such as system depressurization, purging, and hot work. 3. Minimization of environmental impact: No need to discharge the medium within the pipeline, achieving environmentally friendly operations. 4. Maximization of economic benefits: The total cost is significantly lower than that of the traditional shutdown and maintenance plan. The basic principle of pressure-bearing hole opening The core principle of the pressure-bearing opening technology is based on two key technologies: pressure balance and multiple seals: Pressure balance principle: During the operation, a dedicated device is used to establish a balanced cavity at the opening position that is equal to the internal pressure of the pipeline. This ensures that the medium does not spurt out when the cutting tool cuts the pipe wall. This principle is similar to the cabin balance system of a submarine and is the physical basis for achieving safe operations. Re-sealing system: Modern pressure-bearing opening equipment employs at least three independent sealing systems: Axial dynamic sealing: Prevents the leakage of the medium along the rotating main shaft. 2. Static sealing of the chamber: Ensuring the integrity of the operation chamber 3. Valve Sealing: As the final barrier, it ensures absolute sealing after the operation is completed. Part Two: Standardized Process for Pressure-Resistant Hole Opening Maintenance Phase 1: Preparatory Work and Plan Development (accounting for 30% of the total time) A successful pressure-bearing hole-opening repair is 70% dependent on thorough pre-work preparations. On-site investigation and data collection · Precise measurement of pipeline parameters: including outer diameter, wall thickness, material, operating pressure, and medium properties, etc. · Assessment of working environment: spatial limitations, safety distances, escape routes, environmental risks, etc. · Pipeline historical data review: Corrosion conditions, maintenance records, operating years, etc. 2. Technical Scheme Design · Optimization of opening position: Based on stress analysis, the optimal opening point is determined to avoid weld seams and stress concentration areas. · Equipment selection matching: Select appropriate-sized hole-making machines, valves and connecting components based on pipeline parameters. · Emergency plan formulation: Develop detailed response measures for various abnormal situations that may occur. 3. Work Permit and Approval · Work permit processing: This includes permits for hot work, confined space entry, and high-altitude work, etc. · Safety technical briefing: Clearly explain the operation procedures, risk points and control measures to all participants. · Surrounding coordination: Notify the upstream and downstream facilities or units that may be affected Phase 2: Equipment Installation and Pressure Balance (accounting for 20% of the total time) Pipeline pre-treatment · Surface treatment: Completely remove the anti-corrosion coating and rust from the outer wall of the pipeline, revealing the metallic luster. · Welding short circuit: Special short circuits are welded at the designated positions. The welding process requires full-process quality control. · Non-destructive testing: Conduct 100% radiographic testing or ultrasonic testing on the welds to ensure the welding quality. 2. Installation of Key Equipment · Installing the gate valve: Install a full-port valve on the short connection as the first barrier for isolating the medium.