Glass curtain-wall cleaning at a government service centre: drone work at 200 bar, 20 L·min⁻¹
The M400 Cleaning Kit cleaned the glass curtain wall of the Jianye District government service centre in Nanjing at 200 bar and 20 L/min, improving efficiency by more than 50% over manual work.
The job was the glass curtain wall of the Jianye District government service centre in Nanjing. The M400 Cleaning Kit was used at 200 bar and 20 L/min with a 350 g spray gun. Government offices like this have a regular elevation and a large curtain wall, and the work must not disturb daily operations or people at the entrance.
The trade-off between pressure and flow
Pressure decides whether deposits come off; flow decides how fast the job goes. 200 bar is the usual setting for facade cleaning: glass and ordinary aluminium panels take it, and plain dust, bird droppings and light water marks need no more. Raising pressure to gain speed risks scratches on stone and large glass surfaces, so in the cleaning process the distance and angle of the spray gun matter more.
How the facade is protected
- Smart spray gun coupled to the flight controller: automatic swing plus constant-rate ascent for closed-loop control
- A digital twin maps the cleaning path and pressure, so runs can be reviewed afterwards
- The spray gun weighs only 350 g, limiting the effect of payload weight on flight-controller stability
- Pressure and flow are set by facade material, not one set of parameters for everything
What this approach replaces is manual work at height. Beyond the 50%-plus efficiency gain, the bigger point is taking people off platforms and off high work faces — the risk cost of working at height far exceeds the cleaning itself.
How the work is organised
Cleaning needs a stable water and power point on the ground. The M400 kit's pressure washer runs on AC 110–220 V with at least 3500 W peak power and weighs 52 kg; a quick-release handle and four-way locking castors let it move floor by floor through the building instead of running the whole water line to the roof at once.
- Hose length 80 m / 120 m options, giving an 80 m working radius
- Hose rated to 300 bar maximum, system working pressure 200 bar, a full safety margin
- IPX5 rated, so it works in spray and light rain
- Deployed in 15 minutes, so work windows need not wait on equipment setup
Government offices come with more restrictions than commercial towers: foot traffic at the entrance, working through midday, and limits on occupying the road. Work therefore moves in zones and sections across the elevation, keeping each road-occupation window down to the minimum setup-and-pack-up cycle and running several batches a day instead of taking a whole day at once.
