Clean-In-Place (CIP) vs. Clean-Out-of-Place (COP) for Rotary Valves

Clean-In-Place (CIP) vs. Clean-Out-of-Place (COP) for Rotary Valves
Extremely stringent hygiene and purity requirements are very important in many fields, particularly in the food, pharmaceutical, and chemical industries.

It is often necessary to wash and inspect production systems regularly to meet increasingly stricter specifications and remain competitive. There are two options for cleaning rotary valves: Either the valve is washed with the rotor still installed in the system (CIP) or the rotor is pulled out before washing (COP).

Function / Procedure

With CIP, the cleaning liquid is simply run through the rotating rotary valve, for example from a tank or spray nozzles for automated CIP. The rotor remains installed during CIP cleaning, rotating to help transport the washing water further. The valve gap between the rotor and the housing must be designed for the maximum cleaning temperature. Surfaces and geometry are designed for optimal flow and all seal designs are specially engineered to be flush with the product chamber when pressed together. In this way, gaps and dead zones are prevented, ensuring the best possible cleaning results.

If the CIP principle is adhered to completely, equipment must be designed so that it is completely clean and germ-free after automatic cleaning, without additional dismantling and subsequent manual cleaning. This means that there should not be any gaps or dead zones in which the product or cleaning fluid can collect. Fully automatic cleaning saves time and money. It is not necessary to constantly dismantle and manually clean the components. CIP cleaning is particularly advantageous for components that are difficult to access.

The second method (COP), wet cleaning, is to pull the rotor out before cleaning. In this case, the open housing bore is closed with a cleaning plate, a “cleaning aid”, and the cleaning liquid runs through the “rotor-less” valve housing. This method is suitable if the rotor must be cleaned separately, for example in a cleaning system, to remove stubborn caked deposits. This task is easily completed with the Coperion FXS extraction feature (Full Access System) (Fig. 1). FXS1 allows for easy extraction of the rotary assembly from the non-drive side without the need for hoist devices. FXS2 can be combined with FXS1 to allow for easy access on both sides of the valve.

The side plate can be quickly released from the housing, pulled out of the housing with the rotor intact, and swiveled to one side (FXS1). For this purpose, the rotor is provided with a quick-cleaning coupling which permits for rapid separation from the drive-side endplate (Fig. 2).

Advantages of the Coperion Technology

The optimal design of Coperion rotary valves means both side plates of the valve can be opened and pushed to one side (Fig. 1). This is the only effective way to confirm full cleaning on all surfaces between the housing and the side plate, and to further prevent liquid from being within connection points.

Another feature is the .3 rotary design which allows complete removal of the rotary assembly for cleaning purposes. This also allows complete access to the seals on each side of the valve, for complete verification of cleaning.

The optional Full Access System (FXS) hinged extraction feature ensures easy, maximum accessibility and facilitates complete cleaning.

This article is published by

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