求翻译：不论是正常停车，还是异常情况下的紧急停车，加热炉进料降量时要维护局部循环，必须保证炉管内的油品流动，以防炉管结焦烧坏是什么意思？

Whether it is normal parking, emergency or unusual circumstances parking, lowering the amount of feed when the furnace to maintain the local loop, must ensure that the oil flow within the tube to prevent coking furnace burn

Whether it be normal parking, or exceptional circumstances in the emergency stop, reheating feed dropped when volume to maintain local loops, it must be ensured that furnace oil products in the Mobile to prevent furnace coke burning guitar

No matter is the normal cutoff, when in the unusual situation emergency stop, heating furnace feeding falls the quantity must maintain the partial circulation, must guarantee in the furnace tube the oil quality flowing, guards against furnace tube coking to burn out

Both normal parking or the unusual circumstances of emergency shutdown, heating furnace feed down to the maintenance of local loops, must ensure that the oil flow in furnace pipe to prevent the furnace pipe coking in burn out

Whether normal stop, emergency shutdown is also unusual circumstances, heating furnace feed when reduced to maintain local loop, oil product flow in furnace tube must be guaranteed case furnace pipe coking in burned out