Summary of Work on the Three Inspections and Four Fixations for the Equipment

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Summary of Work on the Three Inspections and Four Fixes for the MTBE Plant The MTBE plant began implementing the three inspections and four fixes on March 19, 2012. Prior to that, all employees assigned to various positions received systematic training. The three inspections and four fixes are an effective working method that has been developed over the years. Through the joint participation of various parties, including personnel from installation, supervision, production, design, maintenance, safety, fire protection, environmental protection, and other fields, a thorough and careful inspection was carried out on the MTBE plant. Numerous issues were identified and rectified as a result. These actions were taken to facilitate prompt corrections, thereby ensuring project quality as well as the safe and smooth progress of operations. Given the wide range of people involved in the three inspections and four determinations, hundreds of issues that need to be addressed are typically identified through this process. To handle these issues properly, there is a need for unified principles and understanding; otherwise, disputes are likely to arise. Some major issues need to be decided at the leadership level, and some projects require economic and time costs. To determine which corrective actions to take, we follow the following principles: A) Items that represent omissions during construction or those where the construction work does not comply with standards must be corrected. 2. Those where the original design does not comply with regulations, or where there are significant safety hazards in the original design, must be rectified. 2 |* z% B% |" I8 x& h! ~ 3. Those cases where the original design is unreasonable and makes operation inconvenient should be rectified as much as possible if conditions permit. However, if the rectification requires significant human, material, and financial resources or has a major impact on the project schedule, it can be listed for completion during the commissioning process or maintenance after operation, with the rectifications being carried out gradually during that period. 4. Those cases that are technically controversial and for which a conclusion cannot be reached immediately shall not be rectified yet; a decision will be made after some time of actual production experience. During this process of three inspections and four determinations, we conducted thorough and meticulous inspections of each design drawing, each process technology plan, each control scheme, as well as the installation quality of every piece of equipment, pipeline, valve, instrument, etc., and recorded them in a classified manner. ; E/ R" D. X: ]' x5 L/ Y8 { r! z; n Specific examples (taking omissions in on-site design as an example): b0 M 1. Design omissions; C5 f% {) M5 C, {/ _: r* w% E Large-scale design omissions occur very rarely, but design flaws that affect or hinder production operations are more likely to happen. After the construction of the MTBE plant is completed, especially once the operators have carried out thorough preparation for operation, design omissions can be easily identified. These problems mainly manifest in the following aspects ； a. Omission of necessary isolation valves, crossover lines, vent points, and drain points, etc. 9 T7 I. N* A5 r1 z! B- m& P% C Our equipment makes use of many valves, and most of these valves are used to close or open pipelines; this is especially true for pipelines that require switching operations, as valve closing or opening is frequently carried out during normal production. If such a valve is missed, the operation cannot proceed. ) e+ r0 C) C5 S m/ l* \ The inlet and outlet pipes of cooling equipment, pumps, etc., in the device often come equipped with connection lines (such as bypass lines, warm pump lines, minimum flow lines, etc.). If these smaller-diameter connection lines are overlooked, it will affect normal production operations. Installing venting facilities at the high points of pipelines and drainage facilities at their low points is a basic principle in pipeline design; if there are no such facilities at the high points or low points, the medium will accumulate at those locations when the equipment (unit) is shut down. If the medium is toxic, it can cause poisoning in operators or maintenance personnel. If the medium is flammable and explosive, it may catch fire or explode due to hot work. When there is no vent at the highest point of the pipeline, and if the medium inside the pipeline is a liquid, it can cause air blockages in the pipeline during normal operation. If such air blockages occur at the pump inlet, it can lead to the pump being emptied of fluid. When there is no drainage at the lowest point of the pipeline, it may lead to freezing and other issues in the pipeline. All these issues will affect the production operations of the device (unit). 7 B* x-U; |8 _; t+ m7 o" _. V The above-mentioned problems are the most common ones. Before driving, a thorough inspection should be carried out to ensure that it meets the requirements for production operations. b. The operators cannot access the operation points and observation points, or there is a lack of necessary operation platforms. For manually operated valves, on-site instrument components such as pressure gauges and level gauges, safety valves, spring supports, and other pipeline components, it is necessary for operators to carry out regular or irregular on-site operations or observations during the production process. Such pipeline components should be placed in locations where operators can access them, or appropriate operating platforms should be provided; otherwise, it will affect normal production operations. Similarly, for the operation and maintenance points that need to be accessed during shutdowns, it should also be checked whether they can meet the requirements for such operations and maintenance. In fact, in many production facilities, it is common for individual operation points or observation points to be too high to access. 6 q y/ r- j* R! D* m- {% F (III) Completion documents for the construction were prepared, including the following documents: 6 r, f% c+ J$ {3 Q& B a. Installation records of key pipelines ； ( m% ^+ K4 R+ m4 |, I b. Welding records of the pipeline ； c. Records of non-destructive testing and hardness inspection of welds ； d. Records of strength and tightness tests for the piping system ； e. Purging records of the piping system ； f. Pipeline insulation construction record ； g. Pipeline anti-corrosion construction records ； * y3 ^8 R( Y) ~7 ]$ a, G3 l h. Records of safety valve adjustment tests and inspection records for key valves ； 9 W+ w/ `/ `3 H0 X- y I. Design and procurement change records ； 8 B$ T* R9 {) B/ l9 |. i* D# ~; y i．Other construction documents ； 5 ’ u1 X’ _2 k k. As-built drawings. The inspection mainly checks whether it meets the requirements of the design documents and the relevant standards. 2. Inspection of welding and non-destructive testing records for pipelines. y7 p8 _5 Q | L" I 3. Inspection of records related to strength and tightness tests of pipeline systems. 9 a 4. Inspection of records regarding pipeline system purging. 5. Inspection of records related to pipeline insulation and anti-corrosion work.+ Z8 n: z0 o: A6 J( {, M 6. Inspection of records of safety valve adjustment tests and inspections of key valves; X& b7. Inspection of other construction documents. 8. Inspection of as-built drawings.9 W3 ^) K% z9 p" Q0 f$ `0 H# g II. On-site inspection The on-site inspection covered three aspects: omitted items in the construction, unfinished work, and construction quality. (I) Omitted items in design and construction 4 E/ R% E) y% m The main issues identified were as follows: a. Omissions in terms of valves, cross-connections, high-point venting, and low-point drainage ； b. The operation and measurement indication points are too high to be operated or observed, especially the on-site indication elements of the instrument ； 7 Z+ {" g' }8 R c. Ladders are missing or there are too few of them, making routine inspections inconvenient ； ! M8 H) P2 h. v! |# q' v5 K s, r0 b. The position of the blind flanges (especially the 8-shaped ones) is incorrect; adjustments should be made promptly in conjunction with the operations being carried out ； & O* Q! x* d. ] c. The valves, flanges, bolts, etc., are of incorrect type. S d. The material and pressure rating of the pipes and their components do not meet the design requirements. Through this three-inspections and four-determinations process, 21 design omissions, 245 quality hazards, and 68 unfinished tasks were identified, totaling 334 issues. Any issues identified are promptly addressed, taking a solid step forward to ensure successful operation.