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In the current market economy, it is a common practice to meet procurement requirements by simply specifying the specifications, materials, structural details, dimensions, and model number when placing an order. However, this approach is incorrect; a simple valve model covers only a small portion of the technical requirements, and even those requirements are not fully reflected in the model number. This can lead to information asymmetry between the suppliers and users of valves, resulting in delays in their proper installation and use or even serious accidents after installation. Therefore, it is essential to prepare detailed and accurate technical documents when purchasing valves. ①The scope should clearly specify the focus of the technical specification being prepared, such as the type of valve and the requirements related to it, as well as the project or device for which it is intended. These valves should first be divided into ordinary valves and special valves. Engineers will receive a summary of the valve materials for various devices, which generally includes valves of different types, sizes, and materials. For example, ordinary non-metallic lined valves, ordinary non-metallic valves, ordinary metal valves, high-temperature valves, low-temperature valves, oxygen valves, low-leakage valves, insulated valves, etc. Since the key strengths of different manufacturers vary, the technical bids must be submitted separately. Therefore, in a larger project, more than one technical specification for valve procurement is often prepared, so that the resulting technical documents can better meet the requirements for quoting. ②On-site basic information includes aspects such as environmental conditions, the installation location, and the properties of the operating medium. Indicate whether the valve is to be installed outdoors or indoors ； Environmental conditions include various meteorological parameters such as the monthly average temperature, historical extreme minimum and maximum temperatures, wind speed, relative humidity, etc ； The properties of the operating medium should specify its components and the proportions of those components. For Qizhong Valves, these conditions can sometimes affect the structure and configuration of the products they supply. For example, it is necessary to take into account freeze protection in cold regions, as well as the grade of anti-corrosion coatings and the suitability of various components for different environmental conditions. ③The applied standards and regulations should include manufacturing standards, inspection and testing standards, material standards, etc. In terms of valve standards, American standards include those established by various organizations or valve associations such as API, ASTM, ASME, and MSS, while in China the standards are mostly GB, JB, HG, or SH. Different standards for design, testing, materials, and structural connection dimensions have vastly different requirements. This is reflected in the differing structures, lengths, and configurations of valves, resulting in varying prices as well. Valves manufactured according to ASME or API standards are generally more expensive than those manufactured according to GB or JB standards. When referencing API valves in the SH standard system, attention should be paid to the differences in temperature and pressure values between the two. Especially for carbon steel and chromium-molybdenum steel materials, due to the poor comparability of these materials in terms of application, it often happens that for the same nominal pressure class, the allowable pressure value of SH flanges is much lower than that of API valves at the same temperature. In such cases, it is necessary to increase the strength grade of the flange material appropriately; otherwise, it will lead to a waste of the valve’s capacity. In addition to basic standards such as manufacturing standards, inspection and testing standards, and material standards, all other relevant standards for the product must also be fully filled in; otherwise, it may lead to problems and errors. For example, when the valve is welded together, the standards for its nozzles, the standards for the groove preparation of the joint welds, and the pipe designation should be specified. ④The main technical requirements include several key aspects such as the design and manufacturing of valves, materials, inspection and testing, nameplates, coating, packaging and transportation, submitted documents, technical services, acceptance, after-sales service, as well as warranties and guarantees. a. The material requirements should specify the standards and codes for the materials required for the valves, the names of the materials, their performance grades, and the methods of fabrication. When manufacturing the valves in accordance with these requirements, the valve manufacturer should be asked to provide test reports on the chemical composition and mechanical properties of the relevant materials; for components that require non-destructive testing, non-destructive testing reports should also be provided. b. The design and manufacturing process should, based on the actual usage requirements, include as much information as possible regarding the relevant structural types, structural characteristics, design and manufacturing standards, as well as any special requirements for the valves in question. This enables valve manufacturers to produce valves that meet the actual needs more accurately, based on this detailed description. c. The inspection and testing standards codes for the valve shall be specified in the inspections and tests ； Appropriate inspection and testing requirements shall be specified; if there are special requirements, they must be stated separately with explanations. For components that require non-destructive testing, the methods for such testing as well as the acceptance criteria shall be defined. d. Specify separately, as required, the technical documents that the valve manufacturer must submit during bidding, after ordering, and at delivery. e. Specify the corresponding standards for the coating, packaging, and transportation of required valves, and provide appropriate supplements. Such as surface pre-treatment of valves, type of coating, coating thickness, requirements for packaging and transportation, etc. f. Specify the contents required on the valve nameplate, the material of the nameplate, and the method of fixation. g. Specify the technical services that the valve manufacturer must provide for the valves supplied, following the award of the contract. h. After-sales service, warranties, and guarantees shall be stipulated as needed. i. Specify the acceptance methods and requirements. Acceptance is divided into factory acceptance, delivery acceptance, intermediate acceptance, and final acceptance. ⑤The valve data sheet outlines the specific requirements for valve products that the ordering party submits to Qizhong Valves. It should include the valve code, structural type, actuation method, connection type, nominal pressure, nominal size, quantity, application standards (the wall thickness of the piping connections should also be specified in the case of butt welding), valve body material and its corresponding material standards, valve cover gaskets, valve cover bolts, numbers of internal valve components, stem packing, and any general requirements for the actuator (if applicable) ； For fittings, pipes, etc., it should include the product name, nominal wall thickness, quantity, material, structural requirements, specifications, material standards, application standards, connection type, and other details. Filling out this form is both time-consuming and detailed; any omission can lead to serious mistakes in the procurement process. This is especially true when purchasing from abroad, where it can result in significant financial losses and may affect the progress of the construction project. This is the core aspect of valve procurement; especially for special valves, it is crucial to be able to select the appropriate products in a correct and cost-effective manner. If this step is done properly, then half the work is already done in choosing the right valve. ⑥The technical documents for the negotiated tender regarding special technical requirements differ from the technical annexes used in the final contract, as the manufacturer has not yet been determined at this stage. Moreover, the characteristics of the bidding manufacturers vary, making it difficult to specify certain technical requirements at this time. At this time, some issues that affect product quality can be raised for the manufacturer to answer. For example, the material smelting method intended to be used by the manufacturer, the items for process evaluation, the items for type testing, the pass rate and predetermined criteria for type testing, the condition of delivery, the place of origin, past performance under similar conditions, the delivery deadline, after-sales service, and the quality warranty period, etc. If it is necessary to standardize the basis for quoting, negotiations can also be held regarding factors that affect prices, such as establishing a specified valve leakage level, followed by adjustments based on the outcomes of those negotiations.