Concrete mixer

Application requirement

An industrial mixer system in a concrete plant is used to produce concrete. Concrete is produced by mixing cement, water, additives and aggregates at high speeds and temperatures to form a liquid composite material that hardens over time. Cement mixers are equipped with hatches that are normally used to clean the inside of the mixer. Such machines are interlocked and each hatch is equipped with a mechanical door lock to ensure that operators and/ or maintenance personnel do not gain access until power to the machine has been disconnected. All interlocks are constructed of a complete stainless steel housing specifically designed for continued operation in difficult, dusty environments.

Operating sequence

The key in the key exchange unit operated by the XMSR2 switch, mounted on the mixer control panel, is turned, interrupting the safety contacts and bringing the machine to a controlled stop. In this way, the operator can remove both keys from the key exchange unit and insert them into the corresponding mechanical door lock "DMS1" mounted on the hatch to gain access to the mixer.

Key factors

The Fortress solution includes the following:

• XMSR2 - Switch Operated Key Exchange
• DMS1 - Door lock