Abstract: A closure gate for a coal-loading chute has opposed flat plate closure members for controlling the flow of coal from a storage bin to transport vehicles and the like. Each closure member is provided with opposed seal assemblies engaged with opposed surfaces of the closure member to prevent leakage of coal dust. The seal assemblies comprise elongated, spaced-apart support plates for supporting an abrasion-resistant, plastic seal member characterized by an elongated flat plate which is supported between the seal assembly support plates and is spring biased into engagement with the closure member.