Injury accidents caused by separation of the pump cover from the pump body

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The last edit to this post was made by 402122290 on 2017-9-21 at 11:10. Accident caused by separation of the pump cover from the pump body: 1) Accident details: On November 5, 2001, after taking over their shift at the refining unit of the PTA plant in the Chemical Engineering Department 2 of a certain petrochemical subsidiary, the crew was assigned to carry out operations to isolate pump G1—1221. The team leader issued the work order, and the equipment crew replaced pump G1—1221. At 21:32, power was supplied to the pump to restore the process flow, and meanwhile the control room instructed the personnel on site to start pump G1—1221. The personnel on site first started the G1—1221 pump to test its forward and reverse rotation, then stopped it. At 21:42, after the pump was started for the second time, accompanied by a loud bang, the connection between the pump cover and the pump body suddenly broke apart, and hot water at 3.15 MPa and 242°C gushed out. The team leader and others immediately rushed to the scene from the control room and saw a field operator with blood on his face, walking unsteadily over. After the team leader and others closed the inlet and outlet valves of pump G1—1221, the steam at the site gradually dissipated, and another on-site operator was found lying on the ground in a coma. The people on site quickly took the two people to the hospital. According to the hospital’s diagnosis: 1 person had multiple fractures of the skull, and 1 person suffered a contused laceration on the right forehead (treated with 3 stitches). Despite the hospital’s full efforts to save them, one of them died due to severe injuries at around 22:20 on November 7. 2) Cause of the accident: (1) The G1—1221 pump involved in the accident was a spare pump that had been overhauled by a maintenance branch company from October 8 to October 18. The pump cover of this pump is a new domestic pump cover, manufactured by a chemical fiber machinery factory based on the designs of the original imported parts. During the installation of the pump cover and the pump body, the workers used bolts of the wrong specification; the screw holes in the pump cover (a total of 16) require 7/16″ imperial threads, so 7/16″ imperial bolts should have been used. However, M10 metric bolts were mistakenly employed during installation, which caused the bolts to loosen and reduced the strength of the connection. The pump cover and the pump body separated instantly under pressure, resulting in the accident; this was the direct and main cause of the incident. (2) During the process of assembling the pump cover and pump body, the maintenance workers failed to check and confirm the specifications of the bolts when they had doubts about them; the equipment managers also did not conduct a thorough verification, resulting in bolts of incorrect specifications being installed. (3) The equipment managers at the polyester plant failed to request from the spare parts company the drawings needed for the maintenance and assembly of the new G1—1221 pump. When arranging the work for maintaining and assembling this pump, they did not provide any instructions regarding the detailed changes in the dimensions of the components of the new pump cover. Additionally, defects in the manufacturing of the new pump cover led to misjudgments on the part of the maintenance personnel. (4) When the maintenance personnel at the maintenance branch company were maintaining and assembling pump G1—1221, they did not keep proper maintenance records, and there were missing entries in those records. Upon completion of the maintenance work, the inspection procedures were inadequate, and there was a lack of a strict system for conducting inspections. (5) The polyester plants and the maintenance subsidiaries failed to effectively implement the principle of \"safety first, prevention foremost.\" There were shortcomings in equipment management, and in particular, insufficient education was provided to employees regarding safety awareness and a sense of responsibility. The technical skills and professional capabilities of the on-site maintenance staff were not adequate to meet the actual requirements, which was also one of the reasons for the accidents. 3) Preventive measures: (1) Strengthen safety education for employees, and carry out comprehensive safety inspections to assess the adherence to the principle of \"safety first\", the implementation of rules and regulations, the rectification of safety hazards, and the presence of any violations of safety protocols. (2) Implement strict management of equipment inspection, maintenance, and repair; in particular, it is necessary to strengthen the technical training of maintenance personnel as well as the quality control of such maintenance activities, to ensure that the spare parts for the equipment are in good condition. (3) Strengthen management by organizing all employees to study earnestly, master, clarify, and implement their safety responsibilities, ensuring safe production throughout the factory.