Views:5 Author:Site Editor Publish Time: 2020-05-06 Origin:Site
The cemented carbide pulse nozzle is based on the principle of self-oscillation, relying on the self-oscillation chamber of the nozzle itself to convert the continuous jet into a pulsed jet, that is, the jet flows into the water chamber from the different flow in the upper section of the nozzle The two collision surfaces reflect, and the reflected pressure wave on the upper collision surface is equal to the initial phase of the downward pressure wave of the water flow, forming a superposition of wave patterns; collision with the jet reflected from the lower collision surface generates a strong circular shear stress, The high jet flow is sheared into an instantaneous vacuum to form alternating water bombs. The high pressure generated in the vacuum discharges the water bombs at a high speed, forming a discontinuous water bomb jet. Therefore, the shortcoming of the continuous energy of the existing continuous jet nozzle is small, and the instantaneous striking force of the jet, the effective jetting distance and the hydraulic energy when the jet reaches the bottom of the well are improved.
During the drilling process of the drill bit, the cuttings peeled from the parent rock are easily pressed to the bottom by a large pressure difference, which also produces the so-called "cuttings holding effect". This will make it very easy to form large plastic clumps and form a "pad" between the roller cone drill and the bottom hole rock, which will affect the drilling efficiency and accelerate the wear of the drill bit. The key to improving drilling efficiency is the energy of the jet. The instantaneous jet energy of the cemented carbide pulse nozzle is as much as 1.5 times that of the ordinary continuous jet nozzle. The effective injection distance is also increased by nearly 2 times, and the drilling speed is increased by 20%. -40%. The drill footage is increased by 15% -25%, which makes the pressure at the bottom of the well distributed and promotes the rock breaking. In addition, pulse jet rock breaking has two major advantages: one is that the pulsation characteristics can form a discontinuous and uneven pressure distribution in the impingement circle and the entire bottom of the well; the other is that the lateral diffuse flow can pass through three forms (speed, Kinetic energy and shear stress) effectively clean up the cuttings.