Freezer Maintenance Tips

Excessive belt tension has a large negative effect on both people and self stacking belts. Controlling the tension on your self stacking belt will greatly improve the operation and reduce the maintenance requirements of your self stacking spiral. High tension will cause your belt to wear and elongate which eventually may make it unusable. It can cause rods to break. Excessive tension can also cause the stack to be less stable. This is because the belts pitch increases and decreases in proportion to the tension on it, like a very strong rubber band, it stretches when tensioned and will want to contract when it gets into the spiral. The only way it can contract is by reducing it diameter in the stack. This stack diameter reduction makes the adjacent tiers mismatch in critical areas which can cause them to totally misalign and fall into one another or "destack". Even though the tension limit switch on the in feed stand is not tripping, the tension may be too high for long belt life and dependable operation.

Frequently someone will notice that the belt is not being pulled off of the stack quickly enough and rather than change the sprocket ratio of the take up drive will add more weights to the take up. This will generally solve the problem of belt not coming off the stack fast enough, but will also increase the belt tension all the way from where the product comes off of the belt through the take up and back into the stack. It is far better to change the discharge drive ratio than to add more weights. If an adjustment in drive ratio is needed, be sure to do it in small increments of approximately 1% by changing both the driver and the driven sprocket. Changing only one sprocket is too big a jump and will not give you the right result. Why the out feed drive periodically needs to be adjusted, and how to adjust it will be discussed in greater detail in a future article.

Dirty return rails that may have abrasive particles imbedded in it. Keep the rails clean and never expose the rails to abrasive particles from such actions as grinding or sawing.

Missing friction reducing items such as rollers or rail cap strips that guide and support the belt. Make sure all the guides and rollers are in place.

Obstructions to the belt such as frost, product debris, and interfering fasteners like roll pins should be looked for and removed if found.

I have seen extremely large variations in belt wear rates between freezers. Some plants will wear a belt out in 2 years while others can have a belt look like new after 10 years of intense production. While belt tension is not the only difference between the 2 plants it plays a major role. Reduce stress because belts, like humans will live longer with less of it.