S2.OP-PT.TRB-0003 — Main Turbine Valve Stroke Testing
Purpose
Provides direction for performing periodic stroke testing of main turbine valves, including governor valves (MS28), stop valves (MS29), reheat stop valves, and intercept valves.
Key Actions / Information
Exam — 2022 Q64
P&L step 3.12.3: If any HP turbine inlet valve (Governor MS28 or Stop MS29) closes and does not reopen, reduce turbine load to 75% within one hour. P&L step 3.12.6: If a Reheat Stop Valve or Intercept Valve closes, do not operate above 80% load; do not exceed 5 minutes with any valve closed before beginning to reduce load at 10%/hr. Continue load reduction until either the valve is open or less than 80% load is achieved. Governor/Stop valves have different requirements (75% in 1 hour) than Reheat/Intercept valves (80%, begin reducing at 10%/hr within 5 minutes).
JPM — 2019 Sim-e
Section 5.4.3 Retest on 22MS28 Main Turbine Stop Valve at 89% power. Navigate DEHC HMI to Test Screen (TEST → STOP/GOV TEST). Verify test permissives GREEN: TURBINE INLET PRESSURE OK, NO OTHER TESTS IN PROGRESS. P&L 3.4.3: operate at <=75% turbine load with any one HP inlet valve closed. Record initial positions, SELECT START TEST on HMI. Field operator misses monitoring 22MS28 stroke (alternate path) — must SELECT RESTROKE on HMI to re-verify valve operation. After successful restroke, SELECT END TEST. Record final positions when TEST IN PROGRESS changes to NORMAL OPERATION. OHA G-12 TURB STM STOP VLV CLSD expected during test.
Connections
- Related systems: Main Turbine
- Related exam questions: 2022 Q64
- Related JPMs: 2019 JPM Sim-e
- Related exam: 2019 NRC Operating Exam, 2022 NRC Written Exam