供长输的天然气，其脱水深度以确保在输送过程中水蒸气不致凝析和形成水合物为原则，所以天然气的露点应比管道输气的最低温度低5～10℃。The dewatering depth of natural gas for long-distance transportation is to ensure that water vapor does not condense and form hydrate during transportation. Therefore, the dew point of natural gas should be 5 ~ 10℃ lower than the minimum temperature of pipeline gas transmission.