Howden specifically sought out Shrinkwrap as an established British Manufacturer to build the machine; back up, service and support being a high priority for them in such a high volume operation. The project team had input on the machines functionality and operation throughout the build process, another critical factor for them in the decision making process. Dave Sargeson, Project Manager commented “the engineering quality of the machine is outstanding and the installation was a great success. We are delighted with the overall results and performance of the shrink wrap machine”.
The machine was required to fully enclose and shrink wrap up to 3 metre by 600mm kitchen work tops. Two lengths of work top are wrapped side by side on the machine at a rate of 18 metres a minute.
The Customer’s Brief
The solution will be capable of providing shrink wrap material to all 6 sides of all worktops (total wrap) to protect them against ingress of dust whilst in storage and transit. The shrink wrap will cover the entire laminated surface, underside, front and side edges.
2 identical worktops are simultaneously exited from existing equipment onto the shrink-wrap machine infeed belt. These worktops are a matched pair varying in length from one metre to three metres.
The equipment will be fully automated with zero or minimum change over times, it will require low levels of supervision and minimal manning levels including, where appropriate, design & specification to minimise the necessary maintenance.
Automatic shrink wrapper with 1750mm wide automatic cross seal, unique side sealing tool, centre sealing and cutting device, with automatic size changing facility.
The shrink wrap machine registers that the work tops are approaching the seal bar area. Once the work tops have pushed through the film wall the machine senses the rear of the pack and motorises the seal gantry to move at the same speed as the pack, cutting and sealing on the forward motion. As soon as the seal is made the head retracts and returns ready for the next pack.
As the work tops progress through the sealing section, side sealers tack the sides together and sub divide the pack prior to shrinking. Vertical hot air guns, designed specifically for this machine application, automatically move in and out sealing the sides by bonding the film together. The central duct is operated automatically.
The side sealing and sub division section consists of four grip faced rubber conveyor belts supporting the worktop with small gaps in between to allow cut and seal. The side sealing of the worktops is achieved with the minimum required width of film allowing product identification of each worktop as per Howden’s specific requirement.
The shrink tunnel consists of a Quattro heat chamber system with 4 heater banks mounted in the side of the machine. Each bank of heaters is made up of base heaters and control heaters. Each side is monitored by a temperature controller mounted in the control panel; each blower fan is driven by an AC variable speed controller allowing flow rates to be adjusted accurately.
As the worktop passes through the tunnel various grids and ducts shrink the film leaving an enclosed pack ready for stacking.