山東裝載機在使用過程中突然出現轉斗工作無力和轉到位后自動前傾的現象，但工作中動臂的上升和下降都正常。山東裝載機專家分析可能是分配閥中的轉斗滑閥和轉斗雙作用安全閥出現故障。如果轉斗缸內的油封損壞，則在轉斗作用下，使大腔內的油流入小腔(有桿腔)內，可能導致轉斗自動前傾。分解兩轉斗缸后發現，其中一缸正常，另一缸的油封嚴重損壞。但更換油封后，轉斗還是自動前傾。如果分配閥中的轉斗前傾油路損壞，使轉斗前傾油路中的油流入油箱，也會導致轉斗自動前傾。檢查山東裝載機轉斗滑閥知，滑閥處于正常狀態。如果轉斗雙作用安全閥處常開狀態，也能導致轉斗自動前傾。因為轉斗的大、小腔雙作用安全閥是對轉斗小腔起防止過載和補油作用的。
Shandong loader in use during sudden turn the work of fighting weakness and transferred to automatically forward position, but work in the boom of the rise and fall is normal. Shandong loader expert analysis may be assigned in the rotating bucket valve slide valve and the rotating bucket double acting safety valve failure. If the rotating bucket cylinder oil seal is damaged, in a rotating bucket effect, and a big cavity of the oil into the cavity (cavity of pole),may lead to the rotating bucket automatically forward. After the decomposition of the two rotary bucket cylinder, one of the normal cylinder, the oil seal of the other cylinder is seriously damaged. But replace the seal, the rotating bucket is automatically forward. If the distribution valve in turn bucket forward circuit damage, the rotating bucket forward oil in the oil into the tank, but also lead to transfer bucket automatically forward. Check Shandong loader bucket spool valve, slide valve in the normal state. If the bucket double acting safety valve normally open state, can also lead to the bucket automatically forward. Because of the large and small rotating bucket double acting safety valve is to prevent the overload and the rotating bucket cavity fill oil effect.

拆檢山東裝載機雙作用安全閥后發現，錐閥前端有一黑色小橡膠塊，經辨認，此黑色小橡膠塊是轉斗缸受損油封的殘塊。正常狀態下，錐閥應是閉合的，現小橡膠塊處于錐閥前端，將錐閥頂開使其處于常開狀態，造成轉斗缸卸載、活塞桿收回并通過連桿機構導致轉斗自動前傾。最后，將轉斗雙作用安全閥內的小橡膠塊取出，轉斗即不再自動前傾。
Inspection of the double effect of the safety valve Shandong loader, the end of the cone valve with a small black rubber block, identified, this small black rubber block is a rotating bucket cylinder damaged oil seal. Under normal conditions, the cone valve should be closed, the small rubber block in front end of the cone valve, the cone valve opening at the top so that it is in a normally open state, resulting in a rotating bucket cylinder unloading, piston rod back and through the connecting rod mechanism leads to the rotating bucket automatically forward. Finally, the rotating bucket small rubber block double acting safety valve removed, turning bucket is no longer automatically forward.