Milking Pipeline - Pipeline Cleaning

Pipeline Cleaning

The pipeline and all milk handling systems are cleaned after every milking session using a pipeline washing system that first rinses out the remaining milk and then flushes cleaning solution through the piping to kill bacteria and remove milkstone, a layer of scale mainly formed by cations like calcium and magnesium. The entire washing mechanism is operated very much like a household dishwasher with an automatic fill system, soap dispenser, and automatic drain opener.

The milking pipeline is usually set up so that the vacuum in the system that lifts milk up into the pipeline can also be used to drive the cleaning process. Rather than having a single line run to the bulk tank, typically a pair of lines transport milk by gravity flow to the receiver bowl and transfer pump. The high ends of these two lines are joined together to form a complete loop back to the receiver bowl.

Cleaning is accomplished by inserting a choke plug into one of the lines leading to the transfer pump, and sucking large volumes of water from a wash-water supply tank into the choked line. This choke plug is mounted on a rod, and is inserted into the line before cleaning and pulled out for regular milking. Due to the choke, the water, which is sufficient to completely fill the pipe, is sucked up one side of the pipeline, over the high point joining the two pipeline sections, and then flows back to the receiver bowl and transfer pump through the unchoked line. The transfer pump is then used to move the cleaning solution from the receiver bowl back to the wash-water supply tank to restart the process.

Typically, the inlet ports on the receiver globe are designed so that large slugs of wash water moving at high speed will enter on a tangent to the sides of the globe and rapidly spin around inside to assist in vigorous cleaning of the globe interior. It is normal for wash water to overflow out the top of the globe and for some wash water to be sucked into the overflow chamber to also flush it out. During cleaning the bottom of the overflow chamber is connected to a drain channel on the receiver globe to permit water to flow out.

For the small-farm pipeline, the portable milkers are inserted into this cleaning loop usually by sucking the cleaning solution out of the wash supply tank through the milker claw and outputting from the milker hoses into the choked end of the line. When the water returns to the receiver bowl, the transfer pump returns the water back to the milker's water pickup tank.