... Block tolerance within +/-1mm 2. Production rate over 98% 3. High automatic,low manpower 4. No waste slurry Zhengzhou Dearye Heavy Industry Machine ... ", And passed the ISO9001: 2000 Quality System Certification, possessed the independently Products ... concrete block machine, Autoclaved Aerated concrete block machine, Expanded block machine, Foam block machine New type AAC block making machine DBD Ferry ...