Industrial Valve Inquiry Checklist: How to Fill In Medium, Temperature, Pressure and Connection

Why Organize Medium, Temperature, Pressure and Connection Before Inquiry

The biggest risk in industrial valve inquiries is incomplete information. If you only write "need a batch of valves" or "quote according to drawings," suppliers will find it hard to provide a verifiable solution, and buyers may later find inconsistent specifications during price comparison. Medium, temperature, pressure and connection are the four basic inputs for valve selection: the medium determines material and sealing compatibility, temperature affects the allowable range of materials and sealing forms, pressure determines the pressure rating and wall thickness, and connection determines the connection method and installation feasibility. Only after these four items are clearly organized can an inquiry list be comparable.

Medium Information: More Than Just a Name

Medium is the first item on an inquiry checklist. Writing only "water," "oil," or "gas" is often insufficient. It is recommended to specify at least the medium name, state (liquid, gas, slurry containing particles, etc.), concentration or composition, whether it contains corrosive components, whether it contains solid particles, and whether it is prone to crystallization or polymerization. If it is a mixture, list the main components and approximate proportions. For hydraulic systems, also specify whether it is mineral oil, water glycol, or another medium; for industrial piping, specify whether it is a process medium, utility medium, or auxiliary medium. When medium information is unclear, material and sealing choices can only rely on assumptions, and the solution should be locked only after confirmation with the supplier.

Temperature and Pressure: Give Ranges, Not Single Points

Temperature should include the normal operating temperature and the possible maximum and minimum temperatures, not just "ambient temperature." Pressure should distinguish operating pressure, design pressure, and possible pressure fluctuations or surges. For valves, temperature and pressure must be considered together: the allowable pressure of the same material differs at different temperatures, and sealing materials also have temperature limits. When inquiring, it is recommended to write: "Medium temperature range: __°C to __°C; operating pressure: __ MPa; design pressure: __ MPa; whether there is pressure surge or frequent opening and closing." If parameters are temporarily uncertain, mark them as "to be confirmed" rather than replacing real operating conditions with estimates.

Connection and Interface: Nominal Size, Standard and Direction Must All Be Specified

The connection section is often simplified to just "DN size," but actual installation requires more information. It is recommended to specify in the inquiry list: nominal diameter or pipe diameter, connection method (flange, thread, welding, clamp, etc.), flange standard and sealing face form, pressure rating, valve face-to-face or structural length requirements, operation method (manual, pneumatic, electric, etc.), and installation direction or space limitations. If replacing an old valve, it is best to verify the actual dimensions and standard of the existing connection to avoid installation failure after delivery. Different connection standards may prevent interchangeability even when the nominal size is the same, and this should be confirmed with the supplier.

A Reusable Inquiry Checklist

The following checklist is suitable for procurement to verify item by item before sending an inquiry, and also for maintenance personnel organizing replacement requirements: – Medium name, state, main components, concentration, whether it contains particles or corrosive components – Medium temperature: normal value, maximum value, minimum value – Operating pressure, design pressure, whether there is frequent opening and closing or pressure surge – Nominal diameter, connection method, flange standard, sealing face form, pressure rating – Preferred valve type (such as globe, ball, butterfly, etc.) and operation method – Installation space, flow direction requirements, whether drain or vent connections are needed – Material requirements: specify body, trim and seals separately – Quantity, spare parts requirements, whether material certificates or inspection reports are required – Items you want the supplier to clarify in the inquiry response: selection basis, material list, connection standard, delivery method – Mark uncertain items as "to be confirmed" and list questions requiring supplier assistance

Maintenance Inspection Perspective: Consider Future Replacement During Inquiry

From a maintenance perspective, valve inquiry is not just about buying a new product; it also involves future overhaul and replacement. It is recommended to record during inquiry the installation location, operating frequency, failure history (such as internal leakage, external leakage, sticking) and replacement cycle of existing valves. If there are multiple valves on the same pipeline, unify connection standards and operation methods to reduce spare parts variety. For critical locations, you may ask the supplier for recommended spare parts lists and inspection points, but do not require them to promise specific service life or performance indicators unless there is verifiable evidence. Abnormalities found during maintenance inspection should be used as technical input for the next inquiry, not judged solely by experience.

Common Questions to Confirm with Suppliers

Because specific specifications, agency authorization and service scope must be confirmed according to the actual inquiry, the following questions are suitable for the inquiry stage: What valve type and material are recommended for this operating condition; are the seals compatible with the medium; is the connection standard consistent with the on-site piping; are additional filtration, drainage or actuators required; what documents are included with the shipment; how should spare parts be selected. For uncertain medium compatibility, temperature-pressure combinations or connection standards, explicitly ask the supplier for written confirmation rather than inferring on your own. If special operating conditions are involved, you may request a selection explanation from the supplier, but should not ask them to fabricate parameters or performance records.

Conclusion: Make the Inquiry List a Verifiable Technical Document

The quality of an industrial valve inquiry depends on the completeness of the input information. When medium, temperature, pressure and connection are clearly stated, suppliers can provide comparable responses, and procurement can more easily verify whether the selection matches. It is recommended to organize each inquiry into a reusable technical document, marking which parameters are confirmed, which are to be confirmed, and which require supplier assistance. This reduces repeated communication and leaves a basis for future maintenance and replacement. Specific specifications, authorization and service scope should be based on the actual inquiry confirmation results.