AZO CleanDock® is a system for docking containers at upstream dosing units. Apart from dust-free transfer between dosing units and mobile containers and decoupling from scales, it provides further functions.
This contrasts with the situation when mobile containers are used. The use of this type of system means that there are transfer points between dosing units and the relevant bulk materials container. These transfer points have to satisfy several requirements simultane-ously: First, the target receptacle needs to have a cover lid that prevents foreign matter from getting into the inside of the container during storage time. Residual quantities, which typically stick to the outlet of the dosing unit after dosing operations, should be pre-vented from falling into the plant. Use of special docking systems rules out potential con-tamination of the plant. A sealed connection between the dosing units and the target re-ceptacle while it is docked is critical to avoid dust from accumulating. An additional challenge is achieving maximum flexibility in decoupling the scales. A flexible connection with minimum force shunt is absolutely necessary. De-aeration of the bulk materials con-tainer being filled should be considered as an add-on.
AZO provides container docking to satisfy these requirements with its CleanDock® sys-tem. This is a double-cone system, consisting of a passive part on the container and an active part on the dosing unit. The passive part on the container seals the opening with a spring-loaded lock. The drop tube, which is below the dosing unit and which feeds the product, is sealed with a cone in the active part of the AZO CleanDock®. When the con-tainer is docked, both housing parts (active and passive) are first joined and then locked. Thanks to the flexible connection built into the passive part, a dust-tight join is formed be-tween the dosing unit and the container. The flexible connection is formed of air-permea-ble filter media. This ensures de-aeration of the container in the filling process and a relia-ble air supply flow during discharge. The double cone is moved from the lock position to the open position in order to open the product channel. Typical of the AZO CleanDock® design is the line contact of the four components: active part of housing, passive part of housing, passive part of cone and active part of cone. This principle allows various con-tainers to be docked below several different dosing points without this causing cross-con-tamination of products. This is a particular advantage when handling allergens. In the food sector, products with a strong flavour may also necessitate using strict isolation like this. In firms from the paints and lacquers sector, isolating systems are used to ensure the strict differences in shades.
The AZO CleanDock® allows mass flow rates of up to 25 t/h. Its design is characterised by simple, time-tested components and it affords robust operating performance with emergency running properties. Several tens of thousands of operating cycles have al-ready been implemented in continuous operation without need for maintenance measures.
The AZO CleanDock® double-cone system surpasses conventional docking systems as regards emissions of dust. It effectively prevents generation of dust from the partially or full container. The AZO CleanDock® reliably holds back any product residue, which, in conventional plants, would adhere to the dosing unit after dosing and fall on the floor or into the plant. The connection between the dosing unit and container is secure at all times during dosing thanks to the frictional and form-fitting connection. The AZO CleanDock® aims to keep accumulation of dust below the minimum dust concentration as regards dust explosion. This goal has been met reliably. Any adverse effect on the weighing result due to force shunts is kept to a minimum thanks to the flexible connection. The AZO Clean-Dock® cannot be classed as a containment system. However, where automation and sub-sequent operating cycles are concerned, the AZO CleanDock® compared with the familiar split valve system is far superior.