A wringing device is used to expel fluids from a flexible container contained within an intermediate bulk container (IBC). The wringing device includes a support frame and a carriage movably coupled to the support frame for supporting components thereof. The wringing device includes a nip shaft coupled to the carriage, and a movable nip shaft movably coupled to the carriage proximate to the nip shaft. The movable nip shaft may be biased toward the nip shaft with a biasing device. The wringing device may include one or more drive devices for driving a take-up shaft and the carriage. The wringing device may also include a transport vehicle for transporting the wringing device between different intermediate bulk containers.