Pressure-sealing is an emergency technology for pipeline emergency repairs: the core means for rapid response and safety guarantee. In various fields involving pipeline transportation such as petrochemicals, urban gas, heating and water supply, pipeline leakage is one of the most worrying emergencies during operation. A tiny crack on a high-pressure pipeline could rapidly escalate into a severe medium leakage accident, causing waste of resources and production disruption, and even potentially leading to disastrous consequences such as fires, explosions, environmental pollution, and casualties. In the face of sudden pipeline leakage emergencies, how to quickly and safely complete the sealing and repair without stopping the medium flow is a severe challenge for every pipeline operation and maintenance personnel. The pressure-bearing sealing technology is a key emergency technology developed to address this challenge. It can establish temporary or permanent sealing isolation through special equipment and processes while the pipeline is operating normally and filled with pressurized medium, creating safe conditions for subsequent emergency repair operations. This article will start from the positioning of emergency technology, systematically elaborate on the core value, technical characteristics, emergency response process, and practical application of pressure-bearing sealing in pipeline emergency repairs, demonstrating the indispensable role of this technology in ensuring pipeline operation safety. 1. The suddenness of pipeline leakage and the urgency of emergency response Pipeline leakage accidents have distinct characteristics of suddenness. Whether caused by corrosion perforation, external force damage, material defects, or due to operational errors, natural disasters, etc., the leakage often occurs suddenly without any obvious warning. A pipeline that has been in operation for many years may suddenly perforate due to local corrosion at a certain point; a construction site may suddenly damage the underground pipeline due to improper mechanical excavation; an earthquake or ground subsidence may cause the pipeline interface to crack. The common feature of these emergencies is that the occurrence time is unpredictable, the location is uncertain, the leaked medium may have hazardous characteristics, and the situation develops rapidly. In the face of sudden leaks, the timeliness of the emergency response directly determines the ultimate extent of the accident's impact. Statistical data show that the severity of the consequences of pipeline leakage accidents is positively correlated with the response time - the earlier the discovery, the more rapid the response, and the more appropriate the handling, the smaller the losses caused by the accident. At the initial stage of the leakage, the amount of medium leakage is relatively small. If effective sealing measures can be taken promptly at this stage, the situation can often be controlled. On the contrary, if the response is slow or the handling is improper, the leakage may rapidly expand, and a large amount of medium may leak out, leading to a serious situation of fire, explosion or environmental pollution. During the time window for emergency response, the pressure-sealing technology plays an irreplaceable role. It can quickly establish the seal without shutting off the pipeline, avoiding delays caused by pipeline unloading, and providing valuable time for subsequent emergency repairs. Compared with the traditional "shutdown - unloading - replacement - repair - restoration" operation mode, the pressure-sealing technology significantly reduces the emergency response time, compressing it from several hours or even several days to tens of minutes. This time advantage is of decisive significance in emergency situations. II. The core value of pressure-sealing as an emergency technology The reason why the pressure-sealing technology is regarded as the core emergency technology for pipeline emergency repairs lies in its unique core value. Ensuring the continuity of supply by continuously completing the operation is the primary value of the pressure-sealing technology. For public service pipelines such as urban gas, heating, and water supply, a power outage means that a large number of users will be deprived of gas, heat, and water, causing significant social impacts. For enterprises engaged in continuous production such as petrochemicals and power, a non-planned power outage once may result in economic losses of tens of thousands or even millions of yuan. The pressure-sealing technology has achieved "emergency repair without interruption of supply", ensuring public safety and user interests while minimizing the direct economic losses caused by the accident to the greatest extent. The rapid response to achieve early control of accidents is an emergency feature of the pressure sealing technology. Once a leak occurs, the pressure sealing equipment and personnel can quickly arrive at the scene and complete the sealing operation within the shortest time. Compared with the traditional repair method that requires pipeline shutdown and purging, pressure sealing eliminates the cumbersome preparatory work in the early stage and compresses the entire process from "detecting the leak - responding promptly - implementing sealing - controlling the danger" to the shortest time. This rapid response capability enables accidents to be effectively controlled at the initial stage of their development, preventing the occurrence of secondary disasters. Ensuring zero emission of the medium to guarantee environmental safety is the environmental protection value of the pressure-sealing technology. The traditional emergency repair methods require the evacuation of the medium inside the pipeline. These media may be flammable and explosive oil and gas, toxic and harmful chemical substances, or high-temperature steam or corrosive liquids. The emission of these media not only causes waste of resources but also may cause serious pollution to the surrounding environment. The pressure-sealing technology achieves "zero emission" operations. During the sealing process, the medium remains in a sealed state, avoiding the risk of environmental pollution. Eliminating secondary disasters during pressure-limited operations is the key safety guarantee of pressure-limited sealing technology. At the site of pipeline leakage, the leakage of the medium has created a dangerous environment - flammable and explosive media have formed explosive gas mixtures, and toxic media pose a threat to people's health. If operations such as stopping the flow and purging are carried out at this time, new dangers may be triggered due to improper operation. The pressure-limited sealing technology avoids high-risk operations such as purging and replacement, completes the sealing without stopping the flow, and reduces safety risks during the operation process. The strong adaptability and wide coverage of application scenarios are the engineering advantages of the pressure-sealing technology. Whether it is high-pressure or low-pressure pipelines, whether they are made of steel or PE materials, whether it is crude oil, natural gas, chemical materials or water, steam and other media, the pressure-sealing technology has corresponding process methods and dedicated equipment. This wide adaptability enables it to meet the emergency repair needs for sudden leaks of various types of pipelines. III. Main Process Methods of Pressure-Resistant Sealing Emergency Technology After years of development, the pressure-sealing technology has evolved into a variety of mature techniques, which can meet the needs of different emergency scenarios. The disc-type plugging technology is the most widely used and technologically mature method for pressure-bearing plugging, and it is suitable for emergency repairs of steel pipelines. The principle of this technology is: On both sides of the leakage point of the pipeline, operation holes are made through pressure-bearing opening technology. The disc-type plugging head is then inserted into the pipeline, and after unfolding, it forms a seal with the pipe wall, blocking the flow of the medium and isolating the leakage section. The disc-type plugging technology is reliable in plugging, has a wide applicable pressure range, and is relatively simple to operate. It is the preferred process method for emergency response in pipeline repair. Within the golden emergency time after the leakage occurs, the disc-type plugging can quickly establish isolation, creating safe conditions for the subsequent repair of the leakage point. The cylindrical sealing technology is suitable for emergency repairs of smaller-diameter pipelines. Its sealing head is compact in structure and can achieve single-hole sealing in certain conditions, reducing the number of openings and shortening the emergency response time. For sudden leaks in small-diameter pipelines, the cylindrical sealing method, with its simple operation, rapid efficiency, has become an effective means for emergency repairs. The folding-type sealing technology is a developed technique for large-diameter pipelines. It has unique advantages in cases of sudden leakage in large-diameter pipelines. The folding-type sealing head can be inserted into the pipeline through relatively small openings and then unfolds to form a seal when it reaches the predetermined position, solving the problems of large opening requirements and high operational difficulty in emergency sealing of large-diameter pipelines.