From the outside, rotary drilling rigs appear very large, and upon entering the cab, one feels there are many handles and buttons—overall, it gives a complex impression. But this is indeed the case. From moving and positioning to auxiliary operations under secondary conditions, and then to drilling under primary conditions, there are indeed many required actions. However, to operate a rotary drilling rig well, among the numerous operations, pressurization is the most important!
The pressurization mentioned here is not simply pressing down continuously through the handle, but controlling the pressure magnitude and duration according to different rock and soil layers. The methods are as follows:
Lift pressure, suspension, point floating, long floating, point pressurization, short-stroke pressurization, long-stroke pressurization, pressurization back-pressure
1. How to improve efficiency
Although a rotary drilling rig has many actions, its ultimate function is drilling. How to drill fast and well? Pressure control is certainly important, so the pressurization method must be continuously adjusted according to geology, load, and vibration. Some people begin to question what pressurization is—isn't it just pushing the handle down to apply pressure? This is a mistaken belief. Pressurization is not just applying pressure; sometimes no pressure is needed, only floating, and sometimes back-pressure is needed. In short, only by flexibly applying pressurization can the rig's performance be brought into play and high-efficiency output achieved.
2. Protecting equipment
By flexibly adjusting the pressurization method and force according to the constantly changing load of the drill bit cutting the formation, not only can components be protected, but rapid penetration can also be achieved. Otherwise, if only blindly applying pressure, not only will the rig's load increase, but the drill pipe and drilling tools are also easily damaged.
3. Eliminating hidden dangers
Deviation: Everyone knows that deviation can cause a series of problems such as: carrying the pipe, cage sticking, pipe casting, etc. In certain geological conditions, if pressurization is too rapid, it can cause deviation.
Unlocking: Unlocking a mechanical lock drill pipe requires resistance to fix the drilling bucket. Torque resistance is mainly generated through pressurization, so pressurization becomes the key to unlocking (it is not that pressurization is needed during unlocking). Controlling the pressure magnitude and duration prepares for unlocking and can effectively prevent carrying the pipe due to failure to mechanically lock.
4. Preventing drill pipe drop
When using friction drill pipes and segmented mechanical lock drill pipes (in an unlocked state), especially in hard geology or when slipping without penetration, almost all operators choose long-stroke continuous pressurization. At this time, the drilling bucket penetration is not proportional to the pressurization stroke, so the inner drill pipe is pushed up. When pressurization reaches the bottom and stops or reverses, the pushed-up drill pipe falls, damaging the drill pipe or the pressurization cylinder.
Summary:
Rotary drilling rigs achieve drilling through pressurization and torque. Pressurization and torque are indispensable, but torque load is first generated by pressurization cutting in. Therefore, among all primary condition actions of rotary drilling, pressurization is the greatest. Only by controlling the pressurization force and duration can the rig's optimal performance be exerted.