Krampitz Safety Features Part 8: Gas Pendulum System

All Krampitz tanks and tank containers for highly flammable media are equipped with a gas displacement system.

That is why there are always two associated connections for the filling process in the filling niches for highly flammable media: a connection for fuel filling and a connection for gas return, also called a gas pendulum connection.

The gas recirculation system prevents fuel gases from escaping during filling at our petrol stations.

 

 

And this is how the system works:

When filling from the tanker, two hoses are connected: the filling hose to the filling nozzle and the vapour recovery hose to the vapour recovery connection.

When the tank is filled, the fuel-air mixture that is above the fuel liquid is displaced. Instead of being led out, however, the fuel-air mixture is returned to the tanker via the vapour recovery line.

This prevents the escape of dangerous gases that are harmful to health and the environment.

As an additional protective measure, a safety pendulum valve is also installed at our filling stations.

The safety pendulum valve compensates for pressure differences.

This is because there can be over- or underpressure in the tank.

Overpressure occurs when the tank is filled or when the tank heats up in warm outside temperatures.

Negative pressure, on the other hand, occurs when fuel is removed, for example during the refueling process.

Without a safety pendulum valve, pressure equalization would have to take place via an open ventilation pipe. This would result in fuel gases constantly escaping in an uncontrolled manner.

This does not happen with the safety pendulum valve! And this is how it works:

The safety pendulum valve has a negative pressure module and a positive pressure module. During normal operation, both valves are closed by metal balls. Fuel gases cannot escape.

Only when excess pressure builds up in the tank, for example when filling it, and reaches the threshold of 22 millibars, does the pressure relief valve open. Then the pressure is strong enough to lift the ball.

The pressure can escape and the ball then closes the valve again.

The vacuum module works in the same way. When fuel is removed, a vacuum is created, a suction. From minus 17 millibars of vacuum, the suction is strong enough to lift the ball and open the valve. Air flows in from the outside, pressure equalization occurs and the vacuum is reduced. The ball then closes the valve again permanently.

Whether it is overpressure or underpressure, the pressure equalization happens extremely quickly in real time. The valve is open for half a second, but then permanently closed again. The tank is sealed. Gases can only escape when the pressure is equalized and contaminants stay outside.

Safety pendulum valve and gas pendulum system protects people and the environment from harmful fuel gases and makes Krampitz petrol stations safe.

Krampitz tank system – cubically good