Air-filled sealing rings are primarily used in the gaps between the sealed doors and openings of large machinery and equipment. Due to the influence of processing and assembly accuracy, or the thermal expansion and contraction caused by changes in environmental temperature, the gaps that need to be sealed may vary or change. The range of this variation is generally over 3-5mm, and sometimes may exceed 10mm. Standard sealing strips are unable to achieve the desired sealing effect. In such cases, a sealing product that can change with the sealing gap is required. The air-filled sealing ring is a new technology developed to meet this need.

The expandable portion of the naturally inflated sealing ring (component) retracts into a concave groove. When air is introduced or exhausted through the inlet and outlet nozzles into the sealing ring's airbag, the airbag of the sealing ring (component) deforms under the internal pressure, causing the concave center to bulge outward. It then extends out of the groove and makes a tight contact with another sealing surface, thereby achieving a sealing effect. To release the sealed state, air is expelled through the inlet and outlet nozzles again, causing the expanded portion of the sealing ring (component) to automatically retract back into the groove (to its natural state), detaching from the sealing surface.

An inflatable sealing ring (piece) is a sealing technology used under specific conditions. Initially, it heavily relied on imports, making its cost apparent. However, due to the complex manufacturing process of the finished product, high material requirements, and low pass rates, each type of inflatable sealing ring (piece) used in different applications has unique cross-sectional shapes, circumference dimensions, and direction of circumference. As a result, a large mold must be designed and manufactured for each specification, leading to high production costs. River*Hong Plastic & Rubber Technology Co., Ltd. has successfully researched a large-scale inflatable sealing ring segmented molding vulcanization technology, which can produce inflatable sealing rings with a circumference of 5 to 10 meters using small molds. This not only significantly reduces the mold investment costs but also makes the series development of inflatable sealing products a reality. A single mold can produce inflatable sealing rings (pieces) with any circumference size while maintaining the same cross-sectional dimensions.