... ,road,bridge ,and others 2,durable 3Double drum HJB Double Drum Mortar Mixer 1it is widely used in construction ,road,bridge ,and ... ,and other work place .2,durable 3Double drumApplication :HJB Double Drum Mortar Mixer is main auxiliary equipment of Mortar pump ,it is ... of double drum ,the upper churn mortar ,the lower store the ...