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钻井液流变曲线的一般特点，是有一弯曲段及一与γ轴成一定角度的近似直线段。据此特点，文中提出了一个新的流变模型：τ＝τｓ＋ηｐγ（１＋β／γ）１／２。新的流变方程中有三个独立参数：静切应力τｓ，塑性粘度ηｐ及剪切稀释系数β。试验比较了几个现有的方程，结果表明，新方程的剩余标准差最小，预报精度最高。新方程不但描述了塑性流体的流变性，还可描述多种其他流体的流变性。当τｓ＝０时，描述假塑性流体；当β＝０时，描述宾汉流体；当τｓ＝０，β＝０时，描述牛顿流体。新方程还有一显著的特点，即当γ足够大时，新方程变得与滨汉方程相同。证明了宾汉方程只适用于中、高剪切区的实践经验。
The general characteristics of the fluid rheology curve are a curved section and an approximate straight section at an angle to the γ axis. According to this characteristic, a new rheological model is proposed: τ = τs + ηpγ (1 + β / γ) 1/2. The new rheological equation has three independent parameters: static shear stress τs, plastic viscosity ηp and shear dilution coefficient β. The experiment compares several existing equations. The results show that the new equation has the smallest standard deviation and the highest prediction accuracy. The new equation not only describes the rheology of plastic fluids, but also describes the rheology of many other fluids. The pseudoplastic fluid is described when τs = 0; Bingham fluid is described when β = 0; Newtonian fluid is described when τs = 0, β = 0. The new equation has another notable characteristic: when γ is large enough, the new equation becomes the same as the Binham equation. It is proved that Bingham’s equation is only applicable to the practical experience of middle and high shear zone.