Disposable or recyclable “Pokers” type drop-off ramps

CONCEPT:
The company POFI-Engineering has developed a new solution for the problems of spreading polyurethane foam.
We have created a service for the production of custom-made spreading rakes (pokers) adapted to the specific needs of each of our customers.
We can produce pokers in the desired dimensions, with personalized drop-off points for a very attractive cost.
Our new ramp is based on our expertise in the manufacture of 16S drop-off ramps for 10 years, guaranteeing a uniform and smooth application with each use.
We have also developed fluid calculation software to define the outlet diameters of the ramps according to each flow rate in order to guarantee a gentle drop-off and avoid the creation of bubbles on contact with the facing while optimizing the life of the ramp.
The poker is made of PET, a recyclable material. Some of our customers crush the pokers to mix them with their foam, thus eliminating any waste.

The Importance of Polyurethane Foam Deposition in Continuous Production

Due to changes in blowing agents mandated by new regulations, polyurethane foam production is becoming increasingly delicate and complex. Mastering the manufacturing process has become a key factor in producing high-quality panels. Among the many production parameters to manage, I would like to address the issue of deposition, which involves controlling two factors: the exit speed of the polyurethane foam from the distributor and the method of deposition onto the facing material.
Exit speed: Ideally, the polyol-isocyanate mixture would be deposited onto the bottom facing without disrupting the ongoing chemical reaction. In practice, this is unfeasible due to the flow exiting the mixing head, which imparts a certain velocity to the fluid. The higher the speed, the less time the foam has to react, creating a risk of clogging the distributor. Increasing this speed would require reducing the size of the outlet orifices. However, excessive fluid exit speed causes two problems: the impact velocity on the bottom surface leads to the formation of air and/or pentane bubbles, and the pressure within the mixing head rises, thereby disrupting the chemical reaction (the mixture). This solution is therefore not viable. One theory suggests that the fluid’s impact speed should match the forward speed of the bottom facing. However, calculations and tests have shown that this speed is too low for production: the residence time within the distribution system becomes excessive, causing the foam to react before it even contacts the bottom facing. A rake-style application system generates a speed between 200 and 400 m/min. Tests with other systems have shown that speeds below 100 m/min yield excellent results, yet such speeds are impossible to achieve with a standard rake (POKER) system.

Thanks to our calculation software, we succeeded, and the results confirm this theory.

1. our ramps are available for:
   Sandwich panels
   Paper panels
   Garage door panels
   Slabstock lines