Abstract: Based on Shenhua Hulunbeier 1750 t / a low rank coal upgrading process package development project,the strength of dryer,the critical equipment,was analyzed. According to the operation and process conditions,the load of the dryer was analyzed,and the stress and displacement distribution under itself gravity,horizontal seism load,external mechanical load,high temperature condition and coal gravity were studied. The bending stress and film stress of key location of the dryer were calculated and determined the safety factor of the critical equipment. The results showed that thermal expansion led to structure deformation,the stress caused by temperature load was maximal,while the influence of mechanical load was minimal. The primary general membrane stress of dry was 61. 70 MPa,the sum of primary general membrane stress and primary bending stress was 260. 40 MPa. The design scheme met the material allowable requirements and the design scheme was feasibility. The max axial and radial displacement of the dryer was 44. 60,29. 50 mm. The width of water seal tank,guide plate,scraper height,distance between scraper and cowl flap should be considered at designtime.