Reading a valve survey report: what good evidence looks like

Engineering guide

Browse the BTR VSI knowledge hub for related valve maintenance guidance.

For seat-leak terminology, read our passing valves guide.

The report should preserve the evidence chain

A valve survey is useful only when another engineer can follow its reasoning. Photographs, readings and test conditions should support every important finding.

The report should also distinguish asset condition from maintenance advice. A recommendation without its supporting evidence is an opinion, not a plan.

Start with a consistent record structure. Our per-valve record guide lists the fields needed for later comparison.

Five parts of a defensible report

1. Asset identity. Record tag, line, location, manufacturer, type, size, rating, materials and actuator details where verified.
2. Service context. State fluid, normal operating condition, isolation role, accessibility and known maintenance history.
3. Observed condition. Describe corrosion, fittings, leakage, travel, damage and housekeeping without assigning causes too early.
4. Test evidence. Record the method, instrument, conditions, duration, direction and actual result.
5. Assessment and action. Link each conclusion to evidence, state uncertainty and name the next safe decision gate.

Photographs need captions that identify location and date. A close view should be paired with enough context to show which valve part it represents.

Screening evidence is not confirmation

Noise, downstream pressure rise and flow indication can suggest a passing seat. They do not confirm the cause or a leakage class.

Pressure may change because of temperature, trapped volume or another connected route. Sound can come from a restriction outside the valve. Instrument indication can also be wrong.

A strong report writes “indicates” or “suggests” for these observations. It then names a confirming test, its limits and who must approve it. See field seat-leak testing methods for this distinction.

The same rule applies to hard operation. Rising torque can suggest fouling, corrosion or mechanical damage, but incomplete travel and stop settings remain possible.

Read recommendations as gated decisions

“Inject sealant” is not a complete recommendation. The report should first establish whether in-service injection is possible and permitted.

The valve must have injection fittings in good condition. Its design and service must suit injection, OEM guidance applies, and operations must permit the work. Product compatibility, equipment rating and stop-work conditions follow those gates.

When evidence is weak or consequence is high, the correct action may be further assessment. The report should not turn every fault into a field service sale.

Compare actions with valve criticality. The same symptom can justify different urgency when isolation duty and consequence differ.

Warning signs in a weak report

1. Causes are stated as facts without a confirming test.
2. Readings have no units, conditions, instrument reference or test direction.
3. Photographs lack valve identity, location or useful scale.
4. Terms such as passing, leaking and seized are used as if interchangeable.
5. Actions have no operations gate, stop condition or accountable owner.
6. Missing records are filled with assumptions rather than marked unknown.

Generic priorities such as urgent, monitor or routine need definitions. The report should explain the consequence, evidence and timing behind each rank.

Turn findings into an owned work list

Group actions by immediate safety control, confirmation, planned maintenance and replacement planning. Assign each action to operations, inspection, engineering or maintenance.

Keep the original observation unchanged when later evidence changes the diagnosis. Add the new result, decision and date so the history remains clear.

A survey programme should improve the next visit, not reset it. Our valve survey service creates per-valve records that teams can compare across maintenance cycles.