Brass tube: a kind of non-ferrous metal tube, which is a seamless tube that is pressed and drawn. Copper pipes are strong and corrosion-resistant, and become the first choice for modern contractors to install water pipes, heating and cooling pipes in all residential commercial buildings. Brass pipe is the best water supply pipe.
The high-precision threaded brass pipe is a zinc-containing brass alloy tube formed by precision machining. It has the characteristics of high dimensional accuracy, good mechanical properties, easy cutting, excellent thermal conductivity, high strength and good seawater corrosion resistance. High-precision brass tubes are widely used in electric power (thermal power, nuclear power, etc.) generating sets, petrochemical transportation, seawater desalination, sea salt production, shipbuilding and other marine industries. They are mainly used to manufacture various condensers and heat sources that contact corrosive media. Components such as exchangers, condensers, water and oil pipeline systems, filters, pumps and valves. With the development of related industries, especially the rapid development of electric power, shipbuilding and marine industries, the market demand for high-precision brass tubes is rising rapidly. The brass tube itself is sensitive to stress corrosion cracking. When there are sufficient tensile stress and corrosive medium containing ammonia at the same time, it will cause stress corrosion cracking. There has been a fracture of the brass tube in the empty extraction zone of the condenser. There is a large tensile stress in some brass tubes. In addition, the ammonia content in the empty extraction zone is high. After a period of operation, the stress corrosion continues to intensify, which eventually leads to the brass tube fracture.
Use measures such as stopping use for more than 3 days, emptying the water side, opening the manhole door to ventilate and dry; stopping for a short time, maintaining the circulating pump operation, preventing the deposition of suspended solids in the circulating water and other measures to slow down the corrosion of the condenser. Use the maintenance opportunity to check the corrosion, fouling, and cleaning of the condenser equipment, grasp the first-hand information of the condenser operation in time, and establish an inspection account according to the inspection requirements, standardize the records of the inspection, and standardize the condensation How to make and keep the brass tube sample of the instrument. Since the eddy current flaw detection detects the leaking but not leaking brass pipe, the hidden danger in the brass pipe is found. The eddy current flaw detection is based on the theory of electromagnetic induction. When the probe is close to the conductor, the induced eddy current generated by the conductor affects the coil in the probe The magnetic field caused by the increase of coil impedance changes to identify defects. Eddy current flaw detection plays an important role in grasping the status quo of condenser brass pipes in order to better carry out maintenance work. To check the quality of brass pipes, the eddy current flaw detection work should be strengthened in the maintenance of condenser brass pipes.