What symptoms indicate it's time to replace the compression springs
Applies to Rovema vertical form fill and seal (VFFS) machine models VPK, BVK, and VPR.
There are a number of causes of sealing problems. Different causes (which include film, environmental, mechanical and electronic) normally manifest with different symptoms.
The common appearance of compression spring related sealing problems is when both top and bottom seals are weak on the same side. For example, when looking at your bag you may notice that the seal is weak on the right side of both the top and the bottom of the bag.
This results because compression springs are either working or broken. Normally a broken compression spring results in severely degraded sealing and is quickly diagnosed. Worn compression springs, however, may not be as obvious - except for the poor seal performance described above.
The solution is replace the compression spring kit. There are four kits/machine and Rovema recommends changing all four kits at the same time. That's important to avoid uneven pressure across the seal which would continue to result in inconsistent seal quality and strength.
One may attempt to loosen or tighten the other compression springs to adjust for a replaced compression springs but this is highly inadvisable. If you think about it like headlights on your car you will recall that when one headlight burns out, the other is quick to follow. Compression springs work in the same manner.
The four compression spring kits are installed with two springs at each corner on each side of the jaw - eight total compression springs.
Rovema OEM compression springs offer specific performance advantages. Learn more about that here.
Rovema part numbers include:
Request a quote for replacement springs here