retort machine periodic inspection
Regular inspection rules for sterilizing pots According to the "Regulations for Periodic Inspection of Pressure Vessels": periodic inspection points for sterilizing pots: annual inspection, comprehensive inspection and pressure resistance inspection.
The inspection form can be downloaded at the end of the article.
(1) Annual inspection (external inspection):
Inspection cycle: In order to ensure the safety of the retort machine during the inspection cycle, the online inspection during the operation is carried out at least once a year. The annual inspection can be carried out by the certified sterilizer inspection personnel of the use unit. (may also be borne by the inspection unit)
1. Annual inspection content: The annual inspection of the retort machine includes the use of the unit retort machine safety management inspection, the retort machine body and the operation status check and the retort machine safety attachment inspection.
Main contents of the inspection of the body and operation of the retort machine:
A. Whether the nameplate, paint color, logo and sprayed license number of the retort machine meet the relevant regulations;
B. Whether there are cracks, overheating, deformation, leakage, damage, etc. on the body, interface (valve, pipeline) parts of the retort machine, welding joints, etc.
C, whether there is corrosion on the outer surface, whether there is abnormal frosting, condensation, etc.;
D. Whether the insulation layer is damaged, shedding, damp, running cold;
E. Check leaks, signal holes for leaks, leaks, and check leaks;
F. Whether the sterilizing pot and adjacent pipes or components have abnormal vibration, noise or mutual friction;
G, support or support for damage, whether the foundation is sinking, tilting, cracking, whether the fastening bolts are complete and intact;
H. Whether the discharge (hydrophobic, sewage) device is in good condition;
I. Whether there are overpressure, over temperature, excess and other phenomena during operation;
J. If the tank body has a grounding device, check whether the grounding device meets the requirements;
K. The implementation of the monitoring measures of the retort machine with the safety status level 4 and the presence or absence of abnormal conditions;
L. Whether the quick-opening type sterilizer safety interlock device meets the requirements;
M. Inspection of safety accessories includes inspection and verification of pressure gauges, level gauges, temperature gauges, rupture disc devices, and safety valves.
2. When performing the inspection of the body and operation status of the retort machine, it is generally possible not to remove the insulation layer.
(2) Comprehensive inspection (internal and external inspection):
Comprehensive inspection refers to the inspection when the sterilizer is used for shutdown. The comprehensive inspection shall be carried out by the inspection agency. The inspection period is:
(1) Inspection period:
A. The security status is 1-2, usually every 6 years.
B. The security status level is 3, usually 3-6 years.
C. The safety status is registered as level 4, and the inspection period is determined by the inspection agency. retort machines with a safety status of 4 shall not be used for more than 3 years. During the monitoring of the use, defects should be processed to improve their safety status, otherwise they should not be used.
D. The new sterilizer is generally put into use for the first time to complete the first comprehensive inspection. The next comprehensive inspection cycle is determined by the inspection agency based on the results of this comprehensive inspection.
(2) Comprehensive inspection items and contents shall be carried out in accordance with the “Regulations for Periodic Inspection of retort machines”.
(3) The inspection unit shall carry out the inspection after the inspection plan is formulated according to the specific conditions of the retort machine, and comprehensively evaluate according to the inspection results, and the safety status level. (If the retort machine needs to be repaired and modified, the safety status registration assessment shall be carried out according to the re-inspection result after maintenance.) The inspection and testing organization shall bear legal responsibility for its inspection and test results and the conclusion of the appraisal.
(4) Before the comprehensive inspection, the user should do the preparatory work and should have the following conditions:
A. The user should submit all technical data, calendar year inspection reports, etc., and operation records, maintenance, modification documents, supervision records, etc. of the sterilizer.
B. Auxiliary parts or other objects that affect comprehensive inspection shall be cleaned or removed according to inspection requirements;
C. Scaffolding, light ladders and other facilities for inspection shall be safe and secure (safeguards shall be provided for scaffolding more than 3m above the ground);
D. The surface to be inspected, especially the corroded part and the part which may cause cracking defects, must be thoroughly cleaned. The surface of the base metal should be exposed to the metal body, and the surface of the magnetic powder and penetration test should be exposed to metallic luster;
E. The internal medium of the container to be inspected must be drained and cleaned. Use a blind plate to cut off the source of all liquid, gas or steam from the first flange of the container to be inspected, and set a clear isolation mark. It is forbidden to use a closing valve instead of a blind plate partition;
H, high temperature or low temperature conditions of the retort machine, according to the requirements of the operating procedures to slowly cool or heat up, so that it can be carried out to the extent of inspection work, to prevent damage;
I. The retort machine that can be rotated or has moving parts should lock the switch and fix it firmly. When testing the mobile sterilizer, measures should be taken to prevent movement;
J. Cut off the power supply related to the retort machine and set an obvious safety mark. Verify that the lighting power does not exceed 24V, and the cable introduced into the container should be well insulated and grounded reliably;
K. If on-site ray inspection is required, the transillumination area should be isolated and a warning sign should be set;
L. When conducting a comprehensive inspection, there should be special guardianship and reliable contact measures.
M. When inspecting, use the unit retort machine management personnel and relevant personnel to attend the meeting to assist the inspection work and be responsible for safety monitoring.
N. When the online comprehensive inspection, the inspectors carefully implement the regulations concerning the use of fire, electricity, high-altitude operations, tank operations, safety protection, safety monitoring, etc. to ensure the safety of inspection work.
(5) The sterilization inspection pot with one of the following conditions shall be shortened as follows:
A. The corrosion of the material on the retort machine is unknown or the corrosion rate of the medium to the material is greater than 0.25 mm per year, and the corrosion data determined by the designer is inconsistent with the actual.
B. The surface quality of the material is poor or the stress corrosion phenomenon is found during use.
C. The use conditions are bad or the stress corrosion phenomenon is found during use.
D. After more than 8 years of use, after technical appraisal or confirmation by the inspector that the safe use can not be guaranteed according to the normal inspection cycle, it should be stopped and discarded.
E. Stop using for more than 2 years.
F. Change the use of the medium and may cause deterioration of corrosion.
G. The design drawings indicate that the withstand voltage test cannot be performed. H. There are doubts about other factors affecting safety in the inspection.
(3) Pressure test: Refers to the hydraulic test, or the air pressure test, which exceeds the maximum working pressure after the full inspection of the sterilizing pot. In each of the two comprehensive inspection periods, a pressure test shall be carried out in principle. The designation drawings indicate that the retort machine that cannot be fully inspected or withstand voltage test shall be submitted by the user to be examined by the municipal-level safety supervision agency, and shall be reported to the provincial supervisory authority for the record.
(1) Requirements for withstand voltage test
A. The pressure test may be allowed after the comprehensive inspection is passed. Before the pressure test, the fastening bolts of the connection parts of the retort machine must be fully assembled and securely fastened. The pressure test site shall have reliable safety protection facilities and be inspected and approved by the person in charge of the unit and the safety department. During the pressure test, the inspectors and the use of the unit retort machine management personnel to the site for inspection. No work unrelated to the test shall be carried out during the inspection, and unrelated personnel shall not stay at the test site.
B. The pressure of the withstand voltage test shall comply with the design drawings and shall not be less than the following formula: PT = ηP [σ] / [σ] t Pressure coefficient η of the withstand voltage test
(2) Before the pressure test, the sterilizer should be checked for stress, and the stress value of the circumferential film should meet the following requirements:
(A) In the hydraulic test, the product of 90% of the yield point of the material at the test temperature and the coefficient of the welded joint shall not be exceeded;
(B) In the air pressure test, the product of the 80% yield point of the material at the test temperature and the welded joint coefficient shall not be exceeded.
(3) The pressure test is preferred to the hydraulic test, and the test medium should meet the following requirements:
(A) Any liquid that does not cause a hazard during the test can be used as a hydraulic test medium at temperatures below its boiling point. Water is generally used. When using a flammable liquid for hydraulic testing, the test temperature must be lower than the flash point of the flammable liquid. There should be no fire source near the test site and equipped with suitable fire-fighting equipment;
(B) Hydraulic test with water as the medium, the water used must be clean. When the Austrian stainless steel sterilizer is hydraulically tested with water, the chloride ion content of the controlled water does not exceed 25 mg/L. (
C) Hydraulic test procedure: The hydraulic test procedure refers to pressure test preparation, water injection and exhaust, pressure boosting, pressure holding, inspection, pressure relief and drainage.
1Pre-pressure test preparation: Determine the test pressure, install a pressure gauge that meets the standard requirements and pass the test at the top of the vessel and the test pump (machine) outlet, and prepare the pressure test pump (machine).
2 Fill the container with water and air.
3 When the temperature of the container is the same as the water temperature, start the pressure test pump (machine) to gradually step up and boost. When the pressure is raised to the design pressure or the highest working pressure, check and confirm the situation is normal and continue to increase to the test pressure.
4 Hold pressure for 30 minutes, carefully observe the pressure gauge for pressure drop.
5 After the pressure is maintained, the pressure is gradually reduced to 87% of the design pressure or the maximum working pressure. The inspection is carried out, and the pressure component is checked for deformation or abnormality, and the joints such as the weld and the flange are leak-free.
6 After the inspection, slowly reduce the pressure and drain the water for ventilation and drying.
(D), hydraulic test, meet the following conditions as qualified:
1. No leakage;
2, no visible deformation;
3. There is no abnormal sound during the test.
(4) The gas pressure test of the retort machine should meet the following requirements.
(A) The basic requirements are as follows:
(1) Due to the structure or support reasons, the sterilizing pot cannot be filled with liquid, and the sterilizing pot which does not allow the residual test liquid under the operating conditions, the air pressure test can be specified according to the design drawings;
(2) The sterilizing pot containing flammable medium must be thoroughly cleaned, replaced and sampled and analyzed by steam or other effective means before the air pressure test, otherwise air is strictly prohibited as the test medium;
(3) The gas used in the test is dry and clean air, nitrogen or other inert gas;
(4) The test gas temperature of carbon steel and low alloy steel sterilizer should not be lower than 15 °C. For other material retort machines, the temperature of the test gas shall comply with the design drawings;
(5) During the air pressure test, the safety department of the test unit conducts on-site supervision.
(B), the operation of the air pressure test is as follows:
(1), slowly increase to 10% of the specified test pressure, hold pressure for 5 to 10 minutes, and conduct initial inspection of all welds and joints. If there is no leakage, it can continue to increase to 50% of the specified test pressure;
(2) If there is no abnormality, then step up the pressure according to the 10% of the specified test pressure, until the test pressure, hold pressure for 30 min. Then drop to 87% of the specified test pressure, keep enough time for inspection, the pressure should remain unchanged during the inspection, and continuous pressure should not be used to maintain the test pressure. It is strictly forbidden to press the fastening bolts or apply external force to the pressure components during the air pressure test.
(C) During the air pressure test, the following conditions are met:
(1) There is no abnormal sound in the retort machine;
(2) Check for no air leakage through soap liquid or other leak detection fluid;
(3), no visible deformation. For the retort machine containing flammable medium, if the air pressure test is carried out with nitrogen or other inert gas, the residual pressure of 0.05~0.1Mpa should be retained after the test to keep the seal.
(D) The pressure test of non-ferrous metal sterilizer should meet the requirements of its standard or design drawings.
(V) Air tightness test The retort machine with extremely high degree of toxicity and high degree of hazard or design is not allowed to leak a small amount must be tested for air tightness. (1) Requirements for air tightness test A. The test pressure of the air tightness test shall be equal to the highest working pressure approved by the test. The opening pressure of the safety valve shall not be higher than the design pressure of the container: B. All gas of the air tightness test shall comply with The provisions of the "Regulations".
(2) The air tightness test operation shall comply with the following requirements:
A. The safety accessories should be fully equipped during the test.
B. The pressure rises slowly until the test pressure is 10%, and the pressure is temporarily increased, and the airtight parts and welds are inspected.
C. The boosting should be gradually increased in steps, and each stage should be pressured by 10~20% according to the test pressure.
D. After the test pressure is reached, after the inspection, there is no leakage abnormality, the pressure holding time is not less than 30 min, and the pressure is not decreased, that is, qualified.
E. Do not tighten the bolts when there is pressure.