| 1 | Design standard and scope | Confirm the valve design standard, pressure class, size range, and end connections offered. Check that the proposed design matches the project specification. | A valve’s design and pressure-temperature limits must suit the piping system; standards are not interchangeable by default. |
| 2 | Operating conditions | Provide design pressure, operating and design temperatures, cycling frequency, and any vacuum or thermal-cycling conditions. Request written confirmation of suitability. | Pressure, temperature, and repeated movement affect valve-body selection and bellows fatigue life. |
| 3 | Process-fluid compatibility | Check the proposed body, trim, bellows, and gasket materials against the fluid composition, concentration, contaminants, and cleaning chemicals. | Corrosion and material degradation can lead to leakage or premature failure; compatibility depends on the actual service conditions. |
| 4 | Bellows construction | Request bellows material and construction details, including ply arrangement where applicable, design pressure, rated movement, and documented cycle-test basis. | Bellows are a pressure-retaining sealing component; construction and fatigue performance should be reviewed for the intended duty. |
| 5 | Emissions and sealing tests | Clarify the required leakage criterion and test method. Where specified, request test reports to the applicable fugitive-emissions standard, such as ISO 15848-1. | “Low emission” claims need a defined test method, conditions, and acceptance class to be meaningfully compared. |
| 6 | Pressure testing and inspection | Agree on shell and seat test requirements, inspection stages, acceptance criteria, and documentation before order placement. Request the applicable test records. | A clear inspection and test plan helps ensure the supplied valve meets the project’s specified acceptance requirements. |
| 7 | Materials traceability | Determine whether material test certificates, heat-number traceability, positive material identification, or third-party inspection are required and available. | Traceability supports verification of material identity and compliance with project or regulatory requirements. |
| 8 | Manufacturing quality controls | Review the quality-management certificate’s scope and validity, along with documented procedures for welding, forming, inspection, and nonconformance handling where relevant. | Certificates alone do not demonstrate that a specific valve design or order meets the required technical specification. |
| 9 | Application experience and engineering support | Ask for relevant, verifiable service references and confirm access to engineering review for sizing, materials, installation orientation, and operating limits. | Comparable service experience can help identify application risks, but references should be checked for relevance to your conditions. |
| 10 | Delivery, documentation, and after-sales support | Confirm the delivery schedule, drawing and document submittals, spare-parts availability, warranty terms, and response process for technical issues. | Lifecycle support and complete documentation affect installation, maintenance, and the total cost of ownership. |