There is enough environment capability and self-cleaningaction in this area, so the investigation area can be regarded as a non-polluted area.
长江口区及邻近海域具有较大环境容量和自净能力，故该调查区基本可视为未污染区。
2
Flow area that is 3-5 times that of the equivalent copper tube exchanger and self-cleaningaction contribute to low pressure drop and low fouling potential.
流动面积为等效铜管换热器的3 - 5倍，具有自动清洁功能，因此其压降低，受污染可能性小。
3
The valve is rated for continuous duty. 222c Valves have a short stroke water piston for fast response and dual guide areas have self-cleaningaction.