Beifang Heavy Industry has applied for a patent regarding the removal of the oxide layer from the fracture surfaces of P92 seamless steel tubes, which enables the observation of the original morphology of these fracture surfaces for the purpose of failure analysis

Thread Content

Beifang Heavy Industry has applied for a patent related to the removal of the oxide layer from the fracture surfaces of P92 seamless steel pipes; this patent enables the observation of the original morphology of such fracture surfaces, which is necessary for analyzing cracks in P92 seamless pipes. According to information from the Intellectual Property Office, Inner Mongolia Beifang Heavy Industry Group Co., Ltd. submitted an application for a patent titled “Method for removing the oxide layer from the fracture surfaces of P92 seamless steel pipes”. The publication number of this patent is CN119804522A, and the application was filed in December 2024. The patent abstract indicates that this invention discloses a method for removing the oxide layer from the crack surfaces of P92 seamless steel tubes. This method involves using the scanning head of a laser cleaning machine to target the oxide layer on the crack surfaces of the P92 samples, thereby causing the oxide layer on the surface of the samples to come off and the layer beneath it to become loose ； Prepare a hydrochloric acid solution, and add sodium nitrite as a corrosion inhibitor to this solution; the volume ratio of sodium nitrite to hydrochloric acid is 1:3 to 1:5. Pour the hydrochloric acid solution into a container resistant to acid corrosion ； The P92 specimen after laser cleaning was fixed on a support with its oxidized fracture surface facing downward, so that the oxidized part of the fracture was completely submerged in hydrochloric acid solution. The color of the solution was observed; once the solution turned light blue ； After soaking, rinse with clean water, then soak in the **solution; subsequently, clean it using ultrasonic vibration in anhydrous ethanol. The present invention enables the observation of the original morphology of the fracture surface for crack failure analysis of P92 seamless tubes, providing technicians with the necessary experimental basis.