W.hat Does Dogleg Angle Mean?
Dogleg严重程度（DLS）是在规定的长度上的井筒方向方向变化的量度，通常以每100英尺长的度测量。Dogleg严重程度测量通常在定向调查中的井筒上的两个连续点之间进行。
在石油和天然气行业中，井对齐很少完全垂直。在实践中，井角度不断经历倾斜和方位角的变化。因此，DLS总是存在。极端DLS可能对钻井操作产生不利影响;因此，工程师通常计算DLS以测量钻井期间允许的最大嘟冰。
下面的公式表达了度数/ 100英尺处的Dogleg严重性，并且基于曲率半径。
Dogleg严重性（DLS）= {COS-1 [（COS I1 x COS I2）+（SIN I1 x SIN I2）x COS（AZ2 - AZ1）]} x（100÷MD）
在哪里：
DLS = Degrapte / L00 FT中的Dogleg严重程度
M.D.= Measured Depth between the two survey points in ft
一世1 = Inclination (angle) of the first (upper) survey point in degrees
I2 =倾斜度（角度）的第二次（下）测量点
AZ1 =第一个（上层）测量点的方位方向
AZ2 =第二次（下）测量点的方位方向
T.renchlesspedia Explains Dogleg Angle
D.rilling operations are usually planned for a certain amount of dogleg severity between any two points on a well trajectory. Severe doglegs most often occur due to changes in the geology of the wellbore. For example, hard rock may cause the drill string to deviate from the predetermined path in the horizontal or vertical direction.
一世f the DLS of a wellbore is low, this means that the changes in inclination or azimuth are small over the two points of the survey. Conversely, if the DLS is high, the inclination or azimuth of the bore changes rapidly over the course of its length. The higher the DLS, the greater the potential for problems during drilling.
一世s Dogleg Severity Always a Problem?
简而言之，没有。如前所述，DLS几乎总是存在于钻井操作期间，并且钻井操作者通常规划一定量的允许水平或垂直阱偏差。但是，DLS可以是problematic如果偏差严重。
W.hat Are Some of the Adverse Effects of Excessive Dogleg Severity?
T.he first, and most apparent, problem with excessive DLS is that the wellbore is no longer on the intended or planned path. This can lead to operators having to make time-consuming corrections, which can affect drilling schedule and cost. If corrections are not made, the resulting curvature can be such that the planned casing string no longer fits in the shape of the wellbore.
高嘟凝测量的另一个重要问题被重复磨损在井筒的牧区部分中的钻柱。反复磨损本身可以产生若干其他问题。例如，在孔的特定部分上过度磨损串可以产生称为Keyseat的破旧斑点。这可能导致钻头和底部孔组件变得卡住，因为它们被拉过截面。
E.xcessive abrasion is also associated with high friction. Increased torque and drag caused by the friction between the drill string and the borehole can place additional stress on the drilling assembly and lead to excessive wear of mechanical components.
