Experimental Research on Weight on Bit Fluctuation in Horizontal Well

Some experiments have been done by means of horizontal well drilling string simulation experimental device under different weight on bit and rotary speeds.The experiments result shows that: the WOB fluctuation of horizontal well is a sine wave,the frequency is equal to the drilling string rotation frequency,the weight on bit has little effect to the frequency.The actual WOB is always approximately equal to the nominal WOB.With the increase of the drilling string rotary speed and WOB,the WOB fluctuation becomes more stable.The rotary speed is greater than 52.08 r/min and the WOB is greater than 90 kN are suggested to the actual engineering.