Railcar Discharge Adapter (RCDA) can be used to transition from the railcar’s hopper discharge gate to a vacuum pneumatic conveying line. This device can be inserted between the gate and the grade. It serves as a transition to a pipe stub (4” to 8” line) with a hose fitting, allowing flexibility in positioning of the car by using a flexible hose connection to attach to a trackside pipe manifold where the material can be vacuumed out of the car to its destination or transitioned to a pressure conveying system where it can be sent on to farther distances and/or multiple destinations more efficiently. Each adapter also includes a bleed-air gate to allow for manual balancing of the material-to-air ratio of the conveying system at the pick-up point.
These adapters come in two basic types: Manual clamp and single-operator sled styles. In the clamp style, usually, two operators go out and manually clamp a ~175-pound RCDA to the discharge gate frame and then attach a hose to it. In the sled-style unit, a single operator can take a unit on wheels that is retracted to a low profile (7” to 9”) and then raised up to form a dust-tight connection when under the car. (Note: pneumatic cylinders are provided to allow the RCDA to rise with the car as it loses weight from unloading and raises on its shocks). This type of unit is easier to operate but requires a fairly even surface near the tracks to be pushed around.