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常规泡沫低压钻井工艺技术存在两个问题，一是泡沫的一次性使用．使泡沫钻井成本大大增加、同时严重污染环境；二是由于泡沫流体的可压缩性，随着地面温度、压力的变化，井下泡沫质量、密度等参数也随之变化，增加了施工参数设计计算的复杂性。为解决以上两个问题，优选了泡沫液配方，采用了循环泡沫系统装备流程，使泡沫基液可循环使用，而空气排放到大气中。根据泡沫钻井中井口注入压力、最小泡沫液流量和气体流量、泡沫液柱压力等设计参数，考虑了影响泡沫钻井作业中包含的5个方面的因素：1．将泡沫中的气体组分视为非理想气体，用Hall—Yaro－brough方法计算气体的偏差系数Z；2．由于固相碰撞和摩擦所造成的摩擦损失；3．岩屑的临界下沉速度；4．规定了井口最大泡沫质量为0．96，井底最小泡沫质量为0．55；5．根据岩屑的下沉速度确定气液排量，并规定在同一井深，泡沫流动速度应高出岩屑下沉速度10％，作为安全附加系数。对施工参数进行了系统的计算，并编制了软件程序。经现场6井次施工，均获得成功。
Conventional foam low pressure drilling technology has two problems. One is the one-time use of foam. So that the cost of foam drilling greatly increased, while seriously polluting the environment; Second, due to the compressibility of foam fluid, with the ground temperature and pressure changes, the foam quality, density and other parameters also will change, increasing the design and construction of the calculation parameters Complexity. In order to solve the above two problems, the foam liquid formulation is optimized, and the circulating foam system equipment flow is adopted so that the foam base liquid can be recycled and the air is discharged into the atmosphere. According to the wellhead injection pressure, the minimum foam liquid flow and gas flow, the foam liquid column pressure and other design parameters in foam drilling, five factors that affect the foam drilling operation are considered: 1. Considering the gas component in the foam as a non-ideal gas, calculate the gas deviation coefficient Z using the Hall-Yaro-brough method; Due to solid-state collision and friction caused by the friction loss; 3. Critical cuttings velocity; 4. The maximum wellhead foam quality is set at 0.96 and the minimum foam quality at the bottom of the well is 0.55. Determine the gas-liquid displacement according to the subsidence velocity of cuttings, and stipulate that in the same well depth, the foam flow rate should be 10% higher than the cuttings subsidence speed, as a safety additional coefficient. The construction parameters were systematically calculated and the software program was compiled. After the site construction of 6 wells, were successful.