The Evolution of Skirtboard Sealing Systems
Early conveyor belts did not include specifically designed skirtboard seals. Instead, operators sometimes used spare materials like used belting or large "barge" ropes wedged between the skirtboard and the belt, or loosely held in place by their own weight. While these early systems were cost-effective, they were largely unsuccessful. Materials frequently became caught in the seals, causing increased abrasion along the belt's edge, and operators had no means to adjust or correct the issues.
The first skirtboard seals were fabricated in-house from readily-available materials such as used belting or large “barge” ropes. These primitive sealing systems were pushed down on to the belt edges or held in position by gravity.
Recognizing the critical need for seals at pivotal points, designers began incorporating more advanced systems capable of containing fine-grained materials and dust. Today, many of these systems feature a long strip of elastomer secured against the lower edge of the skirtboard using clamps. Skirtboard seals generally fall into categories depending on their connection to the skirtboard: dropping straight down, extending back inside, or sealing the belt on the outside.
Advanced designs often include multiple-layer elastomers with molded-in flaps serving as secondary seals. These secondary strips create channels that capture fines, gently guiding them along the belt and returning them to the main material flow.
Belt sealing and support components work together to ensure an effective seal to prevent the escape of fugitive material.
Effective sealing requires adequate free-belt distance, which is the belt length outside the skirtboard where seals are typically installed. Unfortunately, this distance is often reduced to maximize load on narrower belts, compromising the effectiveness of the sealing system.