The common failure is not an empty valve list. It is a list that appears complete because every row has a size, class and material, while the information needed to select, manufacture, test and document the valve remains implicit.
01 / Procurement architecture
Separate common requirements from valve-specific data.
The current IOGP/JIP33 S-611 package for API 600 steel gate valves provides a useful document model. It separates a technical requirements specification, procurement data sheet, information requirements specification and quality requirements specification. Together with the purchase order, these define the overall technical procurement package.
Common design, materials, manufacturing, testing and marking requirements.
Project and item-specific selections: size, class, service, materials and options.
What the supplier submits, in which format, at what stage and for what purpose.
Quality system, risk-based purchaser intervention, certification and traceability.
Commercial scope, precedence, quantities, delivery and contractual obligations.
You do not have to copy the JIP33 format for every valve. The principle is the useful part: avoid forcing common technical clauses, item data, document schedules and quality intervention into one unreadable spreadsheet.
02 / Valve list and MTO
Minimum fields for each line item
| Group | Fields to define or reference | Why buyers miss it |
|---|---|---|
| Identity | Item, tag, line number, P&ID, piping class, quantity and service description. | One item can appear in several drawings or operating duties. |
| Valve pattern | Gate, globe, check, ball or other pattern; construction, port/bore, flow direction and installation orientation. | A generic type name hides important internal differences. |
| Size and rating | DN/NPS, Class/PN, pressure-temperature basis and face-to-face/end-to-end requirement. | Nominal class alone does not define the service envelope. |
| Ends | Flanged facing and finish, BW/SW/thread standard, mating pipe wall thickness and internal diameter where relevant. | “BW ends” is not enough to prepare the weld end correctly. |
| Materials | Body, bonnet, closure member, seat, stem, bolting, gasket, packing, overlay and hardfacing. | A single “SS316” column cannot define the assembly. |
| Operation | Handwheel, gearbox or actuator; fail position, power supply, accessories, action time and locking requirements. | Actuator requirements are often issued after valve selection. |
| Compliance | Product, design, testing, fire, emissions, sour-service and regulatory documents with editions. | “As per API” does not identify a requirement. |
| Delivery | Marking, coating, cleaning, preservation, packing, spares, language and data format. | These become urgent only after manufacturing is complete. |
03 / Service envelope
Describe how the line operates, not only its design pressure.
Fluid
- Composition and phase
- Concentration and contaminants
- Solids, scale or slurry
- Corrosion or sour-service concerns
- Cleaning and sterilisation media
Pressure and temperature
- Design minimum and maximum
- Normal operating range
- Maximum differential pressure
- Backpressure and vacuum
- Start-up, shutdown and upset cases
Operation
- Isolation or throttling duty
- Normal, minimum and maximum flow
- Cycles and required action time
- Flow direction and orientation
- Water hammer, flashing or cavitation risk
If the data are unknown, label them as unknown and agree who will resolve them. A visible technical query is safer than a silent supplier assumption.
04 / Connections and interfaces
The valve must fit the piping and the maintenance plan.
For butt-weld ends, supply mating pipe material, wall thickness or schedule, internal diameter and any transition requirements. For flanges, define the dimensional standard, facing, finish and companion-flange compatibility. Include piping loads or support constraints where they are part of the design basis.
Also check stem orientation, actuator access, chainwheel height, insulation clearance, lifting, centre of gravity, removal space and the ability to service packing or internal parts. These are interface data, not cosmetic drawing details.
05 / Quality plan
Set purchaser intervention according to risk.
The quality section should identify the supplier quality-system requirement, approved sub-suppliers or actual manufacturers, quality specification level where applicable, ITP content, hold/witness/surveillance/review points, nonconformance control and release authority.
The activity does not proceed without required purchaser approval.
The purchaser is notified and may attend under the agreed notice rule.
The purchaser observes or monitors an activity, process or associated information.
The purchaser reviews records or supporting information for conformity.
These definitions follow the JIP33 quality framework. The selected intervention level should come from buyer risk and criticality—not from a supplier choosing the least demanding option.
06 / Supplier information
State the deliverable, timing, purpose and final status.
Technical evaluation
Completed datasheet, deviation list, preliminary GA and cross-section, qualification scope, sub-supplier information, delivery plan and preliminary quality/inspection plan.
Approval and manufacture
Document schedule, approved drawings, data sheets, calculations where required, QP/ITP, manufacturing and test procedures, and a production schedule.
Conformance records
Material certificates and traceability, heat treatment, welding, NDE, dimensional inspection, assembly, pressure/functional testing, NCRs and concessions.
Handover record
Final drawings and BOM, certificates, reports, release note, coating/packing records, IOM manuals, spare-parts list and indexed MRB/MDR.
For every required document, define whether it is submitted for information or acceptance, the required timing, format, language, number of review cycles and whether an as-built version is required.
07 / Technical bid evaluation
A deviation list should be a controlled deliverable.
Require the supplier to list every exception, alternative and unresolved item with the proposal. “Comply except as noted in our quotation” is not enough when the notes are distributed across commercial pages, drawings and emails.
| Deviation field | Required content |
|---|---|
| Reference | Exact specification, datasheet or drawing clause. |
| Requirement | Buyer’s stated requirement, quoted accurately. |
| Supplier offer | The proposed alternative, with technical detail. |
| Reason and impact | Effect on performance, interfaces, inspection, delivery, spares and life-cycle cost. |
| Status | Open, clarified, accepted, rejected or incorporated into the purchase order. |
Accepted deviations should be incorporated into the final controlled order documents. They should not remain as an ambiguous email alongside an unrevised data sheet.
08 / Release and close-out
Do not reconstruct the manufacturing record book after shipment.
- Before release.Close technical comments, concessions and nonconformances; verify final inspection and required purchaser intervention.
- Match the product.Compare nameplate, markings, serial numbers, dimensions, coating, preservation and packing with the final valve list.
- Index the evidence.Use a document register showing required, submitted, accepted and as-built status.
- Preserve revision history.Final drawings and reports must reflect approved changes without deleting the decision trail.
- Control release.Define who may issue the inspection release and what documents must be complete before shipment.
Copy-ready prompt
What to send with a first enquiry
Valve list or MTO · P&ID and piping class · service and operating envelope · applicable standards and editions · required materials and ends · operator/actuator requirements · inspection and test scope · document list · marking/packing · delivery need · explicit unknowns and deviations.
Send the information you have. A controlled list of missing data is useful; invented precision is not.
Send a valve list for reviewSources / editorial control
Source basis
- IOGP S-611 Steel Gate Valves (API 600), Version 2.0. Current May 2025 procurement package and TRS/PDS/IRS/QRS structure.
- IOGP S-611Q v2.0 Quality Requirements. CAS, purchaser intervention, certification and traceability.
Review limit: the JIP33 package cited here is for its stated API 600 steel gate-valve scope. This page adapts its procurement logic as a buyer checklist; it does not make every S-611 requirement mandatory for every valve type. A project engineer must tailor the final RFQ.