Cost of salvaging and replacing underwater equipment in sewage treatment plants - Construction team for underwater maintenance and replacement of sewage tank push flow agitator

Cost of salvaging and replacing underwater equipment in sewage treatment plants - Construction team for underwater maintenance and replacement of sewage tank push flow agitator

Cost of salvaging and replacing underwater equipment in sewage treatment plants - Construction team for underwater maintenance and replacement of sewage tank push flow agitator

Salvage of underwater equipment in sewage treatment plants is a complex and dangerous task. The following is an introduction to it:

Construction content and purpose; Due to long-term underwater corrosion, the variable diameter flange of pump 5 # is severely worn and needs to be replaced, and the coupling base is severely worn and needs to be replaced as a whole

Due to limited site construction, a three-layer platform needs to be built here to drill holes and plant reinforcement on the walls and concrete above. The production of the platform must comply with safety requirements. The platform requires a working face width of ≥ 1 meter, a thickness of ≥ 6mm, steel material, a guardrail height of 1.2 meters, and steel material with a diameter of ≥ 30mm (materials selected from the national standard and constructed in accordance with industry standards). Steel structure ladders with protective cages are required for personnel to climb up and down each level of the platform

preparation

Equipment inspection and planning: Conduct a comprehensive inspection of diving equipment, salvage tools such as cranes, grab buckets, underwater cutting equipment, etc., to ensure their good performance. At the same time, based on the type, weight, sinking location, and specific environment of the sewage treatment plant, a detailed salvage plan will be developed, including determining the salvage methods, steps, and personnel division.

Personnel training and safety measures: Personnel involved in salvage operations must undergo professional diving training and safety training, familiarize themselves with the procedures and safety regulations of underwater operations. Prepare necessary safety protective equipment such as diving suits, helmets, oxygen tanks, seat belts, as well as emergency rescue equipment such as first aid kits.

Salvage method

Find the vertical center point of the pipeline and drill a hole above to install the suspension point (drilling on the floor is strictly prohibited), to ensure that the 1200cm diameter pipeline can be suspended vertically for installation.

The pipeline is salvaged ashore to remove surface debris, and then the variable diameter flange is cut and replaced. Cutting edges are processed by breaking, elbows are processed by breaking for welding and installation, and the interior and exterior of the pipeline are protected against corrosion.

Direct lifting method: If the underwater equipment has a small volume, light weight, and shallow sinking position, a crane or other equipment can be used to directly lift it out of the water. During the lifting process, attention should be paid to maintaining the balance of the equipment and avoiding collisions with surrounding objects.

Grab bucket salvage method: For some irregularly shaped equipment that is difficult to lift directly, grab buckets can be used for salvage. By operating the grab bucket, the device is grabbed and lifted to the surface of the water.

Underwater cutting and dismantling method: When the equipment is large or connected to other objects due to malfunction, underwater cutting and dismantling may be necessary. Use underwater cutting equipment to cut the equipment into smaller parts and then salvage them separately.

Float salvage method: fix the float on the underwater equipment, inflate it inside to generate buoyancy, and float the equipment to the surface. This method is suitable for devices that are heavy but have regular shapes.

Precautions

Water quality and environment: The water quality of sewage treatment plants may contain various pollutants and harmful substances. During the salvage process, it is necessary to prevent these substances from causing harm to human health. At the same time, attention should be paid to the complexity of the underwater environment, such as water flow, silt, etc., which may have an impact on salvage work.

Equipment protection: Try to avoid further damage to the equipment during the salvage process, in order to facilitate subsequent maintenance and use. For some precision equipment, special protective measures should be taken.