Aging Criteria and Replacement Cycle for Forced Draft Fan Hydraulic Cylinder Oil Tube FAF30.5-19-1
Q1: How to determine if the hydraulic cylinder connection oil tube is aging after long-term use?
After prolonged operation, the aging assessment for the Forced Draft Fan Hydraulic Cylinder Connection Oil Tube, Model FAF30.5-19-1, should focus on the following criteria:
- Surface Cracks: Inspect the outer wall of the oil tube for crazing, cracking, or delamination, especially at bends and near fittings. If the crack depth exceeds 10% of the wall thickness, immediate replacement is required.
- Deterioration of Sealing Performance: Frequent oil seepage or dripping at the joints, or excessive pressure drop during pressure testing (e.g., leakage during a 5-minute hold in a 0.5MPa air pressure test), indicates sealing failure.
- Wall Abrasion and Corrosion: Visually inspect the tube body for thinning, indentations, or rust/corrosion. Use a caliper to measure the outer diameter; replacement is needed if wear exceeds 5% of the original diameter.
- Changes in Elasticity and Hardness: Aged tubes may become hard and brittle, prone to cracking when bent, or locally soften and deform, leading to difficulty in installation.
- Abnormal Operating Parameters: Fluctuations in the hydraulic system pressure or slow regulation response might be caused by scale buildup or aging blockage inside the tube.
Q2: What is the recommended replacement cycle for the Forced Draft Fan Hydraulic Cylinder Connection Oil Tube?
Based on industry experience and equipment maintenance specifications, the suggested replacement cycle is as follows:
Recommended Replacement Cycles
- Standard Operating Conditions: Conduct a comprehensive inspection and replacement of the oil tube every 3 years, especially in high-vibration areas (such as the FAF30.5-19-1 connection point at the FD Fan hydraulic cylinder).
- Harsh Environments: If the oil tube is consistently exposed to high temperatures (>80°C), high dust levels, or corrosive gas environments, shorten the replacement cycle to 1.5 to 2 years.
- Emergency Replacement: The tube must be replaced immediately, regardless of its age, if cracks, oil seepage, or failure to pass pressure testing are observed.
Maintenance Note: During every overhaul, the tube status should be checked simultaneously. Document the number of cracks, seepage points, and changes in tube diameter. This historical data should be used to dynamically adjust the replacement cycle.

-
Balance Drum DG600-240VM: How It Handles High Pressure and Why Your Maintenance Matters
Learn how the DG600-240VM balance drum regulates axial thrust in 600MW feed water pumps. Includes maintenance tips, clearance specs, and O-ring seal checklists.01-09
-
Feed Water Pump Guide Vane DG600-240-04-13 Maintenance Tips & Parts Checklist
Improve feed water pump efficiency. Learn the 6-step overhaul for DG600-240-04-13 guide vanes, plus a critical checklist for bushings, pins, and O-ring seals.01-08
-
Thrust Disc DG600-240-03-22A: Why it’s the Key to Your Feed Water Pump Overhaul
Stop rotor float and vibrations in your FK6D32 pump. Learn the assembly secrets, heat treatment benefits, and 4-step installation for the DG600-240-03-22A disc.01-07
-
Maintenance FAQ: The SD61H-P61 Self-Seal Ring—Why Your Blocking Valve Still Leaks After You Fixed It
Stop blocking valve leaks. Learn the 2mm gap secret and correct assembly for SD61H-P61 sealing rings, backing rings, and split rings in 300MW-600MW units.01-06
-
Feed Water Pump Inner Cartridge Nut DG600-240-01-07: Small Component, Critical Role
Avoid feed pump vibration and axial shifting. Master the torque, direction, and maintenance pitfalls of the DG600-240-01-07 cartridge nut for FK6D32M pumps.01-05