HYDAC accumulator SBO210-2E1/112A9-210AK SBO200-1E1/112A9-200AB SBO210-0.75E1/663A9-210AK HYDAC manufactures two types of diaphragm accumulators: • Non-repairable (welded) • Repairable (threaded) Construction Both types of diaphragm accumulators have the same basic construction. The difference is in the shell. The welded version has a shell that is electron-beam welded, and therefore cannot be repaired. The threaded type has a shell made up of two halves (top and bottom) which are held together by a threaded locking ring.