As the core equipment for producing Water for Injection (WFI), the long‑term stable operation of a multi‑effect distilled water still depends not only on its initial design quality but also on a scientifically sound and disciplined maintenance regimen. Drawing on our hands‑on experience in precision custom machining of pharmaceutical‑grade components, we have compiled the following key maintenance points, while also offering rapid‑response support for replacement of wear‑parts.
1. Daily Check: Steam Trap Discharge Performance
Each day, special attention should be paid to the drainage condition of the steam traps on the first‑effect evaporator and the first‑effect preheater. Poor drainage-often caused by debris clogging or worn valve internals-can lead to condensate holdup, which impairs heat transfer efficiency and upsets system pressure balance. In such cases, the strainer should be cleaned or the trap replaced without delay. For obsolete or non‑standard trap models, we can custom‑machine valve plugs, seat sealing surfaces, and matching filter assemblies based on on‑site interface dimensions and operating conditions, ensuring responsive and reliable discharge.
2. Regular Inspection: System Sealing and Shutdown Drainage
On a weekly or monthly basis, inspect all piping connections, welded joints, and flange seals for leaks, and verify that all manual/automatic valves operate smoothly and close tightly. Whenever the unit is scheduled to be out of service for more than 48 hours, it is essential to completely drain the accumulated water from each effect evaporator and the condenser, so as to prevent microbial growth or stagnant‑water corrosion under static conditions. For valves suffering from internal leakage or stiff operation, Hansheng Automation can precisely machine stems, gaskets, and actuator couplers based on the original model or customer‑provided field measurements, with material options including 304, 316L, or corrosion‑resistant alloys to meet clean‑service requirements.
3. Annual Mandatory Calibration: Pressure Gauges and Safety Valves
In accordance with national metrological regulations, pressure gauges and safety valves must be submitted for calibration or on‑line verification annually. Additionally, at least once a month, manually lift the safety valve test lever to confirm that the disc moves freely and reseats tightly-this is the most direct means of preventing overpressure incidents. If calibration or testing reveals leakage, reset deviation, or spring fatigue, we can promptly supply custom‑made springs, discs, adjusting nuts, and other replacement parts, while assisting with dimensional verification and material upgrades to minimize downtime.
4. Chemical Cleaning When Performance Declines
When the unit shows a marked drop in production capacity, increased temperature differential across heat exchangers, or persistent conductivity excursions, it usually indicates that heavy scale (calcium, magnesium, or silicate) has formed on the heat‑exchange tubes and evaporator walls, necessitating on‑line or off‑line acid cleaning. Prior to acid washing, sensitive components such as temperature sensors and pressure transmitters should be removed, and threaded ports should be protected with special plugs. Hansheng Automation supports custom manufacture of acid‑resistant PTFE or titanium alloy protective plugs, circulation adapters, and other auxiliary tooling, tailored to your equipment's pipe diameters and thread specifications, ensuring that the cleaning process does not damage original precision mating surfaces. After acid cleaning, the system must be thoroughly rinsed with purified water to neutral pH, and all on‑line instruments should be recalibrated to confirm that the equipment has regained its baseline performance.
In summary, effective maintenance of a multi‑effect distilled water still follows the principle of "daily inspection, weekly checks, annual calibration, and timely descaling"-combining predictive maintenance with prompt corrective actions. Whether you require standard spare parts replacement or restoration of non‑standard components, we are ready to provide flexible and reliable technical support throughout your equipment's entire lifecycle, backed by our capabilities in build‑to‑print manufacturing, reverse engineering, and short‑lead‑time machining.
