The direct expansion method of milk cooling, whereby milk is cooled by coming into direct contact with the evaporator (Cooling plates) is one of the most popular methods of milk cooling within Australia.
The horizontal construction is space saving and the efficient evaporator ensures quick trouble free milk cooling, coupled with the agitator the milk is evenly stirred ensuring optimal heat exchange and prevention of freezing.The agitator doubles to expedite the efficient cleaning via the rotojet cleaning powerball. All internal surfaces are smooth and thus there are no bacteria traps.
High quality stainless steel AISI 304.
Insulation is compact (CFC Free) polyurethane
•IControl system – electronic control system for control of cooling, washing and agitation.
•The IControl system also has an alarm system to alerts of any irregularities.
•Refrigeration units – sized and built to meet Australian standards of cooling and also to meet harsh climatic conditions.
•High pressure cleaning system from a dynamic spray ball integrated in the agitator of the vat.
•Other usual standard components on a Packo vat include: adjustable legs, non return valve
•Highly efficient laser welded evaporator.
•Refer to vat features for more detail.
What is a “Direct Expansion” (DX) Packo milk tank?
The direct expansion system is the most common form of refrigeration used in milk cooling both in the Australian and world markets.
A refrigeration compressor or unit pumps liquid refrigerant too the stainless steel cooling plates (evaporators). The evaporator is a twin skin stainless steel arrangement with a cavity between the two stainless plates. The internal skin of the evaporator has the milk or load that contains the heat while the other side incases the refrigerant that passes through the entire evaporator.
Upon entry the refrigerant which is at a much lower degree of temperature removes the excess heat that is within the milk. The refrigerant carries this heat back to the refrigeration compressor where the cycle restarts thus sending super cool refrigerant back to the milk cooling tank evaporators.
Direct expansion is exactly what the name means, refrigerant used directly to cool via the stainless steel evaporators.
Uses for “Direct Expansion”
Packo milk tanks
For farmers that are small in milk production too intermediate, the direct expansion method is the most efficient and cost effective form of cooling. Larger producers of milk need to look further towards the on call glycol chiller system utilizing the direct expansion system or the full DIB glycol systems.
Direct expansion milk cooling tanks work on the 60% of total volume of the tank. Compressors are designed and sized to be able to cool the milk load at 60% in one milking. The Australian standard of direct expansion is-
22>4 degrees @ 60% volume over 3.5 hours cooling time
In normal milking a farmer would be cooling his/her milk while the milk enters the tank. So a properly designed and sized direct expansion milk cooling tank should be cooled down to 4 degrees and turned off by the time the farmer has left the shed after milking.
Why should I chose a Packo “Direct Expansion” milk tank?
Packo Inox is the world’s oldest manufacturer of milk cooling tanks; the direct expansion system is only one of many forms of cooling systems Packo constructs. But like a baby cutting their teeth, Packo’s beginnings centre around the direct expansion systems.
Countless hours and years of refinement, testing and development is the product you see today which sits behind the Packo name plate. Laser welded evaporators unlike competitors spot welded plates is the first sign that Packo is a technological leader in the industry. Superior wash systems and computerized control systems, designed not only for advancement but also ease of use puts Packo ahead of the rest.
We have a saying at Dairy-Tech Refrigeration, “If you have to clean a Packo tank manually, then you simply have a problem”.
And it is as simple as that, a Packo tank leads all others in the field of not only cooling but also washing technology.
Others have tried but there is only one type of milk cooling tank that is as good as a Packo tank, that is a-“Packo Tank”
Compressors / Units used on “Direct Expansion” Packo milk tanks
No two farms are exactly the same; each has individual needs and requirements that must be meet. Direct expansion Packo milk cooling tanks have countless combinations of refrigeration compressors that can be matched to suit individual and unique milking patterns.
Starting with the economical fully sealed compressors, advancing to the open drive and semi hermetic systems, Packo has the answer. Direct expansion tanks used in conjunction with on call glycol pre chilling systems for large producers. Or be it thermal storage for bad power applications or 1/phase > 3/phase inverter soft start systems, no project or limitation is too large or small.
Accessories like heat recovery utilizing the heat from the compressor which heat hot water for your dairy, or even a fully compatible controller fitted to your Packo tank that enables communication for robotic milking, not a problem.
“The Packo direct expansion milk cooling tank is the answer to all your questions”
For quotes regarding complete installed packages contact 03 5662 3277.