SH51 Combined shrink hooding machine
The combined shrink hooding machine SH51 hoods and shrinks palletized products with tubular heat shrinking film.
The SH45 automatic shrink wrapping machine is a combined machine which, using a single work station, performs the hooding and heat-shrinking operations of the product to be packaged. The SH45 automatic machine uses a reel of shrink film in tubular form equipped with side bellows. In the different versions, up to three film reels can be reached. The film is heat-shrunk on the product by means of a gas-fired ring oven; all functions are controlled by a PLC that manages the automatic and manual operations.
The machine cycle can be divided into two main phases. These phases of the cycle are normally carried out during the feeding phase of the new product to be packaged into the machine or in parallel with the common cycle phases, therefore they do not affect the machine cycle time.
First phase: the preparation of the hood takes place at the rear of the machine.
The reel begins its unwinding until it reaches the size necessary for the pack to be hooded, the height of which is automatically determined by means of a reading system external to the machine itself. The welding and cutting unit prepares the hood just picked up from the reel, welding and subsequent cutting. Once set up, the hood is transported by the mechanical gripping system to the central area of the shrinking arch.
Once the hood has the four flaps spread apart, it is brought to the hooding group consisting of four mobile mechanical pliers. Starting from the center of the hood, with an outward movement synchronized with the opening of the crosspieces, the correct rectangle for entering the hood on the product is formed. The hood thus spread is therefore easily transportable on the pack by the descent of the arch.
Second phase: After the hooding, the shrinking cycle starts. In order to hook the film to the base of the product, a suction device is provided which removes the air contained between the product and the heat-shrink film hood, thus favoring the best adhesion of the film to the product itself. With the product centered in the transport, the machine starts the shrinking phase at this point by switching on the gas-powered hot air heaters.
The oven heaters are switched on intermittently, i.e. they turn on only when the hooded product is ready for the shrinking cycle. The duration of ignition is determined both by the dimensions of the pack and by the thickness of the film, this allows a reduced consumption of gas, adequate only for the time for the shrinkage of the film on the product. When the heaters are switched off, the pack is transferred to the machine outlet and the entry of a new pack to be shrink-wrapped.
Techincal Data | |
Suitable film | Shrinkable polyethylene |
Film thickness | 80 -200 micron |
Electric voltage | 400 V trifase – 50 Hz |
Installed electrical power | 7,5 kW |
Total thermal power | 300 kW ca. |
Gas operation | Methane or Propano-Gpl |
Gas line pressure | 0,5 Bar |
Gas line flow rate | 20 m3/h |
Gas consumption | 0.20/0.25 m3/ciclo ca. |
Noise | < 80 dB(A) secondo norma ISO 11202 |