ASME POM 102:2014 pdf free download.Operating Walkdowns of Power Plants.
3 GUIDING PRINCIPLES
Equipment reliability and performance have parallels. Indications of poor performance are closely tied to those of reduced reliability. Abnormal wear patterns, poor cleanliness, increased corrosion, and mechanical failures, no matter how small, have effects on both unit reliability and unit performance. Identifying the root cause is the first step in improving the overall performance of a piece of equipment and the power-generating unit of which it is a part. While these inspection guidelines are written to ultimately enhance the plant’s performance, all observations should be noted and acted upon.
Nonmandatory Appendices A through M provide details on activities to be completed prior to starting an operating inspection—walkdown.
3.1 Safety Considerations
All plant safety procedures should be reviewed prior to inspecting equipment and shall be followed.
Prior to walking down the operating equipment, it is important to identify all potential hazards that may be encountered. High-temperature and/or high-pressure piping should be located and identified, along with the locations of safety valves and steam traps that may release energy unexpectedly. Maintain a safe distance from rotating equipment and moving parts that are in the inspection—walkdown area.
Refer to Nonmandatory Appendix N for some specific safety considerations.
3.2 Pre-Walkdown Activities
Prior to any inspection, the following documents and information should be gathered and reviewed:
(a) the last inspection—walkdown report
(b) recent operating data from control system historian arid other available archives
(c) recent operating history as recalled by current plant operations staff
(d) actual versus expected performance for the component(s) of interest
C-6 VISUAL INSPECTION
During the walkdown, inspect and record the overall condition of the 1-IRSG, including the following:
(a) any unusual noise and vibration.
(b) corrosion.
(c) gas leakage.
(d) steam piping — check for leaks and corrosion points.
(e) drum vents — should be verified to be closed and not leaking.
bypass and letdown lines — should be verified to be isolated, using both local and control system indications for downstream temperatures and flows (as available).
(g) sky vents — should he verified closed and not leaking.
(h) pipe insulation — record any damaged or missing sections.
(1) ductwork.
(1) Check for hot spots on exterior ductwork. Hot spots usually occur in areas where there are missing liner plates and the insulation has broken down due to exposure to flue gas. There are also areas where the liner plates are intact (possibly warped) but there is insulation breakdown. In this case, the breakdown of insulation may have been caused by moisture degradation of the insulation.
(2) Areas where the ductwork paint has stripped off and there is metal discoloration may be duc to hot spots. They can also be found using a thermographic camera.
(3) Check for any openings (or cracks) in ductwork that allow flue gas to escape. Leaks can often be identified by the discolored smear flue gas leaves on the ductwork.
(4) Check for water collection points. These points are susceptible to corrosion and may develop weep holes.
(j) expansion joints and supports guides.
(k) bypass stack (if present) — inspect the damper, guides, and ductwork of the bypass stack. Visually inspect and record any physical damage that is visible externally. Check that insulation is intact using thermography; pay particuLar attention to the expansion joints and the blanking plate.
(I) fuel supply piping.
