3 Scope of Works
Milmeq Carton Freezing and Chilling Tunnels
To meet the demands of the meat, fish, chicken and dairy industries Milmeq have designed a range of fully automated carton tunnels. These carton tunnels have been designed to freeze or cool cartoned or blocked products.
Our motivation in the continuing development of this mechanised conditioning concept is economy and reliability of operation, with the minimum possible maintenance. Whilst the initial cost is not always the lowest, over a period of time our mechanised tunnel offers the most economical approach to carton conditioning.
Description of Tunnel
The MILMEQ Carton Tunnel consists of a horizontally and vertically braced portal frame structure of beams and columns. Suspended on rails within this frame are two sets of pallets or multi-level shelves. The cartons to be frozen are loaded and unloaded onto these shelves mechanically.
The evaporators for the refrigeration plant are positioned at the end of the pallet support frame.
The air blast from the fans passes through the wall of refrigeration coils or evaporators, over the cartons to the far end wall, then returns back down the sides to repeat the cycle.
The evaporators are designed to remove the product heat from the circulating air-flow within the carton dwell time.
Mechanical Cycle of Operation
A pallet load of warm cartons is pushed by actuators onto the tunnel rails of the top pass, and as each new pallet is introduced into the stack at the load end, it pushes another out at the transfer end onto a waiting cradle. The transfer cradle next lowers this pallet down to the lower pass rails, where a second set of actuators pushes it back into the support structure. This action ejects a pallet from the bottom pass at the load end onto a waiting cradle.
Cartons on the shelves of this ejected pallet will have received their required dwell time in the air blast and the product will be down to temperature. At this point the top shelf of cartons will be unloaded onto the feed-out conveyor.
Cartons of fresh product previously assembled on the load conveyor will then be loaded onto the top shelf.
The pallet will index up shelf by shelf, unloading and loading as it rises to the top pass, where it again enters the air blast to repeat the freezing cycle.
All functions for loading, unloading and for pallet movements are electrically interlocked within the control system, so no function can be performed out of sequence. All circuits are failsafe, preventing mechanical damage to machinery or product. Every action is sensed at both ends of the travel by switches feeding information back to a PLC.
Product feed to the tunnel is normally on a “one in/one out” basis, so all cartons will receive the full 24 hour requirement within the air blast