Tips for moisture prevention and rust removal of the electrical system of single-beam bridge cranes

Environmental control: Prevent the intrusion of moisture and corrosive media

Optimization of electrical cabinet sealing

Sealing strip replacement: Regularly inspect the sealing strip of the electrical cabinet door frame. If it shows signs of aging or cracking, it should be promptly replaced with a weather-resistant silicone sealing strip to ensure sealing performance (IP rating ≥ IP54).

Ventilation port protection: Install dust-proof filters (mesh size ≥100) at the ventilation ports of electrical cabinets, and regularly clean the dust to prevent moisture carrying dust from entering the cabinet.

Temperature and humidity regulation:

Heater configuration: Install a thermostatic heater (with power selected based on the cabinet volume, such as 0.1 kW/m³) inside the electrical cabinet, set a temperature threshold (such as 5°C), and automatically activate it when the ambient temperature falls below the threshold to reduce humidity inside the cabinet.

Dehumidifier linkage: In humid areas (relative humidity > 75%), a small dehumidifier can be installed to remove moisture from the cabinet through condensation, maintaining humidity at ≤60%.

Protection of cable entry

Use of waterproof connectors: When cables pass through electrical cabinets or equipment enclosures, waterproof connectors (such as IP68 grade) are used for sealing to prevent moisture from infiltrating along the cables.

Cable tray sealing: At the connection between the cable tray and the electrical cabinet, fill the gap with fire-resistant putty or sealant to prevent moisture from entering the cabinet through the tray.

II. Protective treatment: Enhancing the moisture and rust resistance of components

Surface protection of electrical components

Three-proofing paint spraying: Apply three-proofing paint (moisture-proof, salt spray-proof, mold-proof) to the surfaces of components such as control boards and wiring terminals, with a thickness controlled between 30-50μm. After spraying, it needs to be cured for 2 hours in an environment at 40℃.

Galvanizing treatment: For metal wiring terminals, brackets, and other components prone to corrosion, hot galvanizing process (with a zinc layer thickness of ≥65μm) or spraying zinc-based anti-rust coating (such as Dacromet coating) is adopted.

Touch point protection

Application of conductive paste: Apply conductive paste (such as silver-containing conductive paste) to contact areas such as terminal blocks and relay contacts to reduce contact resistance (≤50mΩ) and prevent oxidation and corrosion.

Spring pressure adjustment: Regularly check the spring pressure of the contacts of contactors and relays. If the pressure is insufficient (e.g., the contact closing pressure is less than 0.5N), adjust the spring or replace the contact to ensure reliable contact.

Cable protection

Selection of armored cable: In humid or corrosive environments, armored cables (such as YJV22 type) are preferred, as their outer steel tape can effectively prevent moisture from infiltrating.

Cable laying slope: When laying cable trays, maintain a slope of 1%-2% to avoid water accumulation and set up drainage holes at low points.