New Generation Mobile Crushing and Screening Plant Closed Circuit Type Dragon 9. DRAGON 9 – Mobile Closed Circuit Crusher and Screening Plant – New Technology Limestone, River Stone, Mining Crusher. DRAGON 9 – Closed circuit crushing system is all collected in one single platform and can be transported with a truck.The R-D group has designed this series for short term installation .Stone Crusher Plant Production Process. First of all, break the big stone boulders to smaller size manually. Then it is fed to the stone crusher. The crusher can accept the stone size of 175mm. Stone crushing is the two-stage process. In the first. stage, crush the 175mm stone to about 50mm. Thereafter, fit the crusher with a conversion kit to.