vertical overhead valve是什么意思

用法例句

The feasibility of substituting vertical retort gas by mixture of natural gas and producer gas is discussed,and the verification is conducted by inspection,test and practical application during natural gas conversion.

论述了天然气与发生炉煤气的掺混气替代直立炉煤气的可行性,通过检测、试验和在天然气转换过程中的实际应用进行了验证。