BLOWER CONCERNS WHEN USED WITH AIR PACKERS
Some of our customers question our stance on the need for individual blowers for each force flow packer. Some are trying compressed air systems, single large blowers, and other concepts that may not lead to successful installations. The following is an attempt to clarify our position and detail our concerns.
STONEPAK’s Current policy is as follows: All performance guarantees (accuracy and rate) for force flow packers are based upon the use of a dedicated blower, of adequate capacity, for each packer (spout).
Though a few of our customers, through diverse means, have successfully used compressed air schemes or fewer than the recommended number of blowers, we strongly recommend that one dedicated blower be used to supply low pressure air to each packer. We offer a blower package which provides up to 150 scfm of air at up to 6 psig. This package includes a weighted relief valve which provides a relatively stable air pressure at the bag filler through rapid changes in the volume requirements during various stages of the filling cycle.
The purpose of the blower is to provide a high volume of low pressure air for both fluidizing the product and conveying it into the bag. An adequate air supply is critical to the bagger’s ability to quickly fill bags. Likewise, the blower’s ability to quickly adjust to volume needs and then provide consistent flow is critical to the packer’s accuracy performance. The final few seconds of the packer’s filling cycle are crucial to accuracy. Typically the packer reduces product flow to dribble to provide an accurate fill. Product flow must be consistent during this period; stable air pressure and volume are essential to a stable product flow through the bag filling machine.
Experience has shown that a single air supply will produce problems when used for multiple bag packers or baggers. This occurs when one packer is in the critical dribble stage and another packer is started or reaches final cut-off. Packer start and cut-off both produce pressure and volume “spikes” in the air supply, which affect product flow through other bagging machines supplied air from the common source.
Our service representatives are very much aware of the packer’s air supply needs. If a customer supplied system is not performing adequately, our representatives will likely recommend our blower assembly and bill for the service call.
