Piston Valve Applications: Windscreen Washing

M&M Piston actuated valves can be used in a wide variety of applications, in this blog post, we are going to provide some examples of the type of application that they have been used in and the type of valve that we would recommend for the application.

Piston actuated valves used in automatic windscreen washing equipment:

The equipment is used to clean portholes during navigation.

In the past portholes were cleaned during the day by cleaners on moving trolleys. The hydraulic system was made up of pilot operated solenoid valves that sprayed water at 80 bar with dangers to passengers. The solenoid valves were not perfectly synchronized and did not close at the same time, so at the end of every cycle water left inside the circuit mixed with rust and dripped on the portholes.

Nowadays both the logic and the hydraulic system have been revisited. The system is totally automatic, it is operated in the control room and cleaning is usually carried out at night to avoid dangers to passengers. Pilot operated solenoid valves have been replaced by PAVs operated by direct acting solenoid valves. The quality of water has been improved as well; it is now mixed with air at lower pressures. PAVs suitable for controlling water are equipped with travel switches to guarantee that they open simultaneously.

1^st stage– Cleaning

Valve (A) controls water taken from a tank and pumped into the circuit by pomp (P) at the pressure of 4-5 bar.

Simultaneously valve (B) controls air from compressor (C) at the pressure of 6 bar. Water mixed with air is sprayed on the portholes by a system of perforated pipes. 

Pipes line the whole length of the ship and are perforated next to each porthole.

2^nd stage – Drying

Once the cleaning stage is over, valve (A) closed so that only air enters the circuit. 

Sprayed air dries the portholes and prevents water left inside the circuit from dripping

The valves that we recommend for this application are:

You can view the V-Flow Solutions range of M&M Piston actuated valves here:

V-Flow Solutions: Piston Valves


You can read the rest of V-Flows blogs here.