The Impact of Mixer Blades in Batch Foam Machines on Product Quality

When using a batch foam machine for polyurethane soft foam foaming, have you encountered the following situations?

1.Uneven and numerous foam pores,

2. Rough foam texture.

3. Chaotic pore sizes across the entire foam surface, with slight signs of large pores.

Issues like these are quite common. The main reason for the first issue is that the distance between the mixing impeller of the foam machine and the bottom of the mixing barrel is too great; the second issue is that the mixing blades are too short and narrow: the third issue is that the angle of the mixing blades is too large.

Many manufacturers who design and produce foam machines only understand the principles during the design process, without understanding the significant relationship between a different design in foam production and product quality. A reasonable and perfect mechanical design can only be gradually improved in actual work, and only experienced foamers can achieve this.

Here are some experiences we have had with machine modifications and upgrades, hoping they will be helpful:

First, the installation position of the mixing wheel should be as low as possible, closer to the bottom of the mixing barrel is better. In general, the distance between the lowest point of the mixing blade and the bottom of the mixing barrel should be around two centimeters

Second, the shape of the mixing blade should be fan-shaped, with a moderately wide edge. The advantage of being wide is that it increases the contact area with the liquid material, providing sufficient power and also balances the liquid material.

Third, the length of the mixing blade should also be as long as possible, leaving about three to four centimeters from the baffle inside the mixing barrel.

Fourth, the two edges of the mixing blade should be sloped, with the angle of inclination based on the width of one end and two centimeters difference on both sides. After the mixing blade is modified, proper operation is also crucial, especially the mixing speed. Most batch foam machines nowadays are equipped with high-speed timing frequency conversion devices. However, in actual production, this device is often unnecessary. The operating speed mainly depends on the amount of material in the mixing barrel. If there is a lot of material, the speed should be appropriately faster, and if there is less material, then the speed should be lower.