Ejector V-Type

Common issues

• Erosion of the motive nozzle and throat from cavitation if driving pressure exceeds design point
• Blockage of the suction or motive line by debris (no moving parts means it cannot clear itself)
• Loss of suction/lift performance from wear of the venturi profile over long service
• Flange gasket leakage from vibration or thermal cycling
• Corrosion or pitting of wetted parts, especially where dissimilar metals are in contact in seawater service
• Reduced motive fluid supply pressure from an upstream valve not fully open or a fouled strainer

Inspection checklist

• Motive (driving) fluid pressure checked against the design operating point
• Achieved suction/vacuum and discharge flow checked against expected performance
• Visual/borescope check of nozzle and throat for erosion or pitting
• Upstream strainer condition and cleanliness
• Flange bolting and gasket condition
• External corrosion of body and connections
• Audible check for cavitation noise at running conditions

Service intervals

Typical intervals for this design class, not the manufacturer’s figures for your model. The manufacturer’s manual is binding.

Typical wear limits

Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.

Critical spares

• Motive nozzle
• Venturi/throat liner
• Flange gasket set
• Flange bolting (material matched to body to avoid galvanic corrosion)
• Body seal/O-ring set where fitted

Safety

• Pressurised motive fluid supply (steam or water) - burn/injection injury risk from any leak or joint failure
• Positive isolation and lock-out of the motive supply required before opening the unit for inspection
• Incorrect body material for the duty fluid can fail under pressure without warning signs

Class survey

Assessed as part of the bilge/ballast/stripping piping system survey - condition of body and valves, correct segregation of oily vs clean systems, and documented performance checks are what surveyors look for rather than the ejector itself in isolation.

Estimated lifetime: No rotating or wearing parts, so life is governed by erosion/corrosion of wetted surfaces rather than running hours - commonly many years in clean-fluid duty, considerably less in abrasive or dirty bilge/ballast service.