Dare to struggle and forge a brand new realm. Huahang Divers, Aquanauts, and Underwater Ghost Company offers underwater engineering services along rivers, coasts, and other aquatic areas. The recovery team specializes in diving operations, with Huahang being a diving industry leader characterized by ample construction personnel, comprehensive diving equipment, and expert service techniques. The recovery team excels in underwater engineering fields, utilizing advanced skills such as underwater recovery, cutting, welding, inspection, filming, and leak plugging. Before divers descend, a telephone operator conducts a test call to confirm the reliability of the diving equipment. Only after the equipment is deemed reliable is the dive operation permitted. During diving operations, it is crucial to listen carefully to the diver's questions, ensuring clear and concise communication. Every 2-5 minutes, inquire about the underwater operation status. During underwater construction, it is strictly prohibited to engage in idle chatter that may disrupt the work.
HwaHuang Divers, Aquanauts, and Underwater Ghost Company Offers: 1. Underwater operations, sediment removal, underwater welding, underwater cutting, underwater cleaning, underwater decontamination, underwater debris removal, underwater leak sealing, underwater filming, underwater photography, underwater mud removal, underwater leveling, reservoir sediment cleaning and sealing, underwater construction, underwater measurement, underwater services, underwater maintenance, underwater inspections, reservoir repairs, underwater photography, underwater dredging, underwater exploration.
Unfavorable weather conditions for rescue operations include strong winds, thick fog, heavy rain, thunderstorms, low temperatures, and high temperatures, among others. Adverse hydrological conditions mainly involve relatively fast river currents, a high number of passing vessels, large waves, and a complex underwater riverbed environment, all of which affect the recovery work and pose significant difficulties for both recovery operations and safety management. Recovery work is conducted both on the surface and underwater, with the complex underwater conditions posing risks and challenges. Underwater recovery employs underwater electro-oxygen cutting, which requires high precision. Adaptability: During the diving recovery process, in the event of an emergency, the original plan or schedule may be subject to necessary adjustments or changes, which is a common occurrence during construction. From July to September each year, when the weather is hot, many people either go into the river for a moment of coolness or to fish for shrimp and prawns, resulting in unforeseen incidents. This is why the term "recovery" is often heard each year. So, does recovery always have to be like "searching for a needle in a haystack"? 1. The major challenge of recovery is the difficulty in locating the drowned and the high failure rate of rescue operations.
Before entering the water, each staff member must be well-versed in the underwater environment. They must also have a detailed understanding of the structure to be repaired. Additionally, they should be thoroughly familiar with the entire repair process. Upon entering the water, it is crucial to have a clear understanding of the local hydrological conditions, especially the underwater environment, temperature, and flow rates. This will help staff select appropriate equipment. When performing underwater welding or any destructive or reconstruction work, proper protective measures must be taken. After completing repairs to leaks or other structures, a thorough confirmation is essential to avoid the need for a second repair. Underwater staff must be aware of the pool's structure and the conditions before divers enter the water. A confirmation of completion must be made after the repair work. These steps are indispensable.
The data indicates that within a 14.66m range symmetrically above the main arch ring, the bridge dimensions are thickened, with some parts being 1.79m thick and others 75cm thick. The total volume of concrete for the entire main arch ring is 138.6 m3, and the total weight is 332t. The thickened section of the main arch ring at the top is divided into 4 horizontal and 7 vertical sections, totaling 28 cutting units. The first 12 units are cut first, followed by units 13-24, leaving the longitudinal units 25-28 at the centerline of the bridge. At this point, the main arch ring is not yet fully severed longitudinally. Before cutting, all supports at the bottom of the arch must be checked again, ensuring the top of the supports align with the bottom of the main arch ring. Bridge cutting construction for caisson work: ① Cutting of bridge deck and abutment arches: Before cutting, calculate the confirmed overall cutting plan. Label each section of the concrete to be cut and design the parking positions for cranes. Due to the main arch ring, the two sides form two cantilever structures, and the cantilever ends (i.e., the cutting points of the main arch ring) will produce minor. Underwater recovery - underwater cutting
Underwater cutting skills are not a continuous process like land cutting; underwater operations require it. The underwater environment determines the difficulty and complexity of underwater engineering, with common theoretical foundations and application methods. Many techniques used on land are not suitable for underwater use. Underwater thermal cutting is a widely used cutting method, accounting for over 90% of all underwater cutting. When using thermal cutting to cut underwater, it is necessary to consider the significant consumption of the heat source itself in the surrounding medium. The main difference between underwater cutting and land cutting is that air is a mobile mixture of gases, while water is a rather viscous and dense liquid; air is combustible while water is flame-retardant. Additionally, water has a higher thermal capacity and thermal conductivity than air, making it more difficult to heat objects in water and faster to cool them compared to air. Therefore, the larger the flame surface in contact with water, the greater the temperature difference, and the greater the heat loss. Although there are various types of underwater cutting techniques, they differ based on their fundamental principles and cutting conditions.
It is crucial during construction to closely monitor for any sawing-in-concrete occurrences. If present, the work must cease for inspection, and a level instrument should be used to check for significant settling on both sides of the main arch to prevent overturning accidents. During this construction, when the main arch was cut, observations showed minor settlements (about 2mm) on both sides after the cut, but they soon stabilized; no other parts of the arch showed signs of collapse or cracking. After the thickened section of the main arch was removed, the remaining main arch on both sides could be cut into 12 units per side, with cuts made separately on the ascending and descending lines. Safety measures for construction: (1) According to high-speed and road administration requirements, close the traffic lanes, set up safety warning signs, and assign a dedicated person to manage traffic. In the overhead lane support archway section, neon lights displaying the archway outline are installed to help drivers judge the space range for vehicle passage at night. Underwater bridge cutting and removal construction scheme: Discussion on the underwater cutting and removal technology and key points: When reconstructing these elevated bridges, it is inevitable to remove a part, while ensuring that the other part remains unaffected and can be reused, which has become a common practice.
Divers, frogmen, and underwater ghost companies should understand how to use signal lines and pre-arranged communication methods. It is necessary to tie signal lines in deep water, fast currents, and around pipes, reservoirs, etc., to facilitate communication in case of malfunctions. When two or more diving recovery teams are working in the same area, they must constantly check their air supply hoses and signal lines to prevent tangling. Items and equipment needed for underwater work should be handed over using ropes to prevent throwing. Signal line handlers and hose pullers must constantly monitor the tension of the signal lines and air supply hoses. Regularly inquire about the underwater work situation to prevent accidents. When two diving teams work together, the diver who finishes their task must wait on the diving ladder until the other diver joins them before removing their diving gear. Diving air supply hoses can be selected as floating or heavy-duty based on the work environment; floating hoses should be used for installation and removal underwater, while heavy-duty hoses are preferable in culverts, dams, or areas with deeper water and higher currents.
Diving supervisors must hold a diving supervisor certification, and life support technicians must have a life support technician certification. Individuals engaged in maritime operations should possess a maritime safety and rescue certificate, divers involved in non-destructive testing should have a non-destructive testing certification, those engaged in underwater welding should have an underwater welding certification, and personnel involved in other underwater activities (such as high-pressure water jets) should have relevant certifications. Huahang Underwater Engineering Co., Ltd. is a private enterprise. Our company has multiple construction teams, including 68 divers, 9 diving supervisors, 6 diving engineers, 2 diving technicians, and a total of 168 full-time employees. Our divers hold "Diver" certifications issued by the Shanghai Salvage Bureau, and the company owns imported diving equipment, laying a solid foundation for high-quality projects. Our diving company specializes in various underwater operations, including underwater installation and maintenance, underwater concrete bag construction, underwater recovery diving, underwater track installation and modification, reinforcement of port and channel wharf piles, underwater cutting and welding, sealing of municipal sewage pipelines, underwater leak plugging, underwater inspections, underwater installation and cleaning of sewage treatment plant fences, underwater wharf and dock cofferdam repairs, underwater cutting and removal of bridge steel piles, sonar underwater searches, underwater ship bottom leak repairs, underwater gate inspection and maintenance, and underwater bricklaying in sewage pipelines. In fast-flowing rivers like the Yangtze and Yellow Rivers, with wide search areas, the salvage team uses sonar detection technology for recovery. Once a human-shaped object is detected underwater, divers are sent down for recovery. During underwater recovery operations, the team ensures the stable operation of equipment, requires all on-water salvage personnel to wear life jackets, and sets up warning lines in the recovery area.
