钻井液振动筛叠层筛网透筛率的研究

从理论上详细论述了钻井液振动筛叠层筛网对固相颗粒分离的影响 ,首次提出用透筛率的概念定量地描述这一影响 ,并进行了实例计算。研究表明 ,当上下层筛网随机叠加时对透筛率的影响有以下几种情况 :(1)当上下层筛网开孔尺寸相除的余数为零 ,任意组合叠层筛网的透筛率分别为某一常数 ;(2 )上层筛网目数一定时 ,下层筛网目数越大 ,则透筛率越小 ;(3)上下层筛网的目数相差越小 ,透筛率越小 ;(4 )任意目数的上下层筛网随机叠加后 ,其透筛率仅在一个小范围内变化 ,因此任一叠层筛网有其固有的透筛率属性。

An investigation in percent through screen of layer vibrating screen on shale shaker for drilling fluid

The influence of layer vibrating screen of drilling fluid shale shaker on separation of solids are expounded theoretically. It is put forward for the first time to use the concept of percent through screen to describe quantitatively this influence, and a case calculation is presented. Investigation shows that, the influences of random lamination of two screens on the percent through screen include: (1) when the remainder of the division of upper and lower screens is zero, the percent through screen is a constant; (2) when the number of the mesh of the upper screen are given, the bigger the number of mesh of lower screen, the smaller the percent through screen; (3)the smaller the difference between the meshes of the upper and lower screen, the smaller the percent through screen; (4)as for the screen with random laminated upper and lower layers of arbitrary mesh number, the percent through screen varies only in a small range, therefore arbitrary layer vibrating screen has its build-in attribute of percent through screen.