Introduction to our company's quality assurance measures

　　I. Raw Materials:

　　1) Upon arrival of each raw material, the supply department immediately notifies the warehouse and testing laboratory to verify the list of qualified suppliers and certificates. If there is a discrepancy with the plan, it is not allowed to enter the warehouse, and it is reported to the company for record-keeping and assessment. If all items match the physical goods, the testing department is notified to take samples for testing.

　　2) After receiving the notification, the testing department immediately dispatches personnel to sample according to standard methods, conduct physicochemical index testing, report the test results on the same day, or provide the test results the next day due to testing procedures, and fill in the determination results according to the raw material quality index regulations, along with a written explanation and test results reported to the production technology and quality department and the supply department.

　　3) Before storing raw materials, the raw material area must be checked for cleanliness. Raw materials must not be directly stacked on unclean grounds. Various raw materials should be classified and clearly stacked.

　　II.

　　Raw Material Inspection and Selection:

　　1) Raw materials after entering the factory must be graded, inspected, selected, and stored, removing substandard materials.

　　2) The inspected and selected raw materials should be clean. Mill materials should be coarsely selected and debris and impurities removed, and clearly separated for storage.

　　3) The workshop and production technology and quality department are responsible for supervising spot checks. If substandard inspections are found, rework must be reported immediately.

　　III.

　　Crushing and Grinding Processing:

　　1) Before production or when changing product types, the quality inspector should check whether the entire medium crushing and screening system is cleaned, including crushers, rollers, elevators, vibrating screens, hoppers, and lower machine pits.

　　2) During production, the quality inspector should handle problems promptly and report them to the technical quality inspection department. Yuzhou Ke Run Refractory Materials Co., Ltd.

　　3) The testing department measures the particle size once per shift. If non-conformances are found, immediately notify the batching worker to stop batching, find the cause, re-screen and separate the qualified materials before resuming batching and production.

　　IV. Mixing:

　　1) For batching and mixing, the quality inspector checks the accuracy and sensitivity of the weighing instruments every day before batching. If inaccuracy or insensitivity is found, personnel are immediately dispatched for repair and calibration.

　　2) The quality inspector randomly checks the weighing errors of operators at least twice per shift to ensure that they are within the specified range, checks whether the correct raw materials are used, and verifies the mixing time and checks whether the work area has any foreign objects such as cigarette butts, wood chips, bricks, etc. If problems are found, work must stop immediately, and the issue must be addressed and reported.

　　3) The testing department samples and tests the slurry 1-2 times per shift. If it does not meet the process requirements, it should immediately stop proceeding to the next process, find the cause, and rework.

　　V. Forming:

　　1) Adhere to sampling inspection. Every shift, the quality inspector must check the overall appearance, dimensions, and cross-section of the last brick坯 from the previous shift and the first batch of brick坯 of the current shift to confirm that it meets the process card requirements before mass production. A comprehensive inspection should be conducted every two hours, and any problems should be addressed immediately.

　　2) Unscheduled spot checks of operators' weighing, pressing, measuring, unit weight, and stacking should be conducted. If any irregularities such as inaccurate weighing, insufficient unit weight, reduced pressing or cold pressing, dimensional deviation exceeding the limit, and serious stacking of defective products are found, correction should be made immediately. Those who repeatedly violate regulations or repeatedly commit the same mistake should be immediately notified to the workshop for processing, and reported to the production technology and quality department and the factory office for record-keeping and assessment.

　　3) The production technology and quality department conducts a comprehensive spot check of the formed brick坯 every shift. If the pass rate reaches 95% or more, the output is recorded and piece-rate is applied. If it is lower than 80%, it is treated as scrap, and the workshop and team are held responsible for the accident, and a summary assessment is conducted at the end of the month.

　　VI. Firing: Yuzhou Ke Run Refractory Materials Co., Ltd.

　　1) Before loading the kiln, the testing department should check that the moisture content of the brick坯 is ≤ 0.3% before entering the kiln.

　　2) Before entering the kiln, the quality inspector checks whether the filling material in the kiln and the sand seal, electrical system meet the requirements. The dimensions of each part of the kiln car and the brick placing method should be strictly controlled, and all equipment is operating normally.

　　3) The quality inspector should regularly check the quality of loading and unloading the kiln. Defective products caused by loading and unloading are recorded and archived. If it exceeds 1%, immediate correction is required. For mass defective products, overturning and mixing are considered accidents, and the workshop and the person at the time are held responsible and reported for assessment.

　　4) Strictly follow the heating system and heating curve operation. (Note: The nitriding kiln should control the kiln pressure regularly according to the requirements).

　　VII. Finished Product Inspection, Selection, Acceptance, and Warehousing:

　　1) Products after unloading from the kiln are inspected and selected piece by piece according to national standards (or user standards), including dimensions, appearance, and layering according to GB10326. For fully qualified products, they are stacked by model and material. The quality inspector must conduct random checks and confirmations. If non-conforming products are found, immediate rework is notified.

　　2) The testing department conducts random sampling and testing in batches and kilns according to sampling standards, conducts comprehensive testing of physicochemical indicators, and strictly follows national inspection standards for testing standards. According to the test results, the determination results are filled in against the product physicochemical index requirements, and a quality assurance certificate and certificate of conformity with legal liability for the user are issued. The written explanation, along with the test report, is submitted to the production technology and quality department and the sales department and finished product warehouse. Only after all physicochemical indicators pass the test can warehousing procedures be handled.

　　VIII. Packaging and Transportation:

　　1) The quality inspector continuously checks the packaging quality, and products awaiting inspection are strictly prohibited from packaging. Substandard products are prevented from leaving the factory. If any wrong packing, mixing, loosening, or unclear marking is found, immediate correction is required, and the supply and marketing department and production technology and quality department are informed for record-keeping and assessment.

　　2) Each brick type is clearly marked on the surface, and the packaging is reasonably concentrated by model. The outer packaging box indicates the material, quantity, and brick type of Yuzhou Ke Run Refractory Materials Co., Ltd. The packaging of each type of unshaped material must match the physical goods and must not use other non-original material packaging.

　　3) Domestic products are transported by truck to the designated location of the buyer. Waterproof and anti-collision measures are taken.