Bearing Housing

I. Core Functions of Bearing Housing

1. Positioning and fixing the bearing components: The inner wall of the bearing housing is usually designed with structures such as steps, which can cooperate with the protrusions and other components on the transmission shaft to precisely clamp and fix the core load-bearing components such as thrust bearings and radial bearings, avoiding the displacement of the bearings due to severe vibration, axial or radial loads during the drilling process, and ensuring that the bearing assembly can stably perform the load-bearing and anti-friction functions.

2. Dispersed transmitted load: During drilling, the drive shaft is subjected to the huge axial drilling pressure and radial deflection force transmitted by the drill bit. The bearing housing, through a tight fit with the bearing assembly, evenly transmits these concentrated loads to itself and other connection parts of the drilling tool, preventing excessive local loads from causing premature deformation or failure of the drive shaft or bearings, and enhancing the load-bearing capacity of the entire drive shaft assembly.

3. Protecting internal components: As a protective casing, it can isolate the drilling fluid underground and the solid particles such as sand and mud within it, preventing the internal precision components like transmission shafts and bearings from being eroded and ground.

II. Typical Structural Composition of Bearing Housing

Its structure is designed around bearing fixation, sealing protection, and ease of disassembly and assembly. There are slight differences in details among different models. Common structures are as follows.

1. Main body shell: The mainstream is a combined structure of an upper shell and a lower shell. The two are mostly connected by threads, and sealing rings are installed at the connection points to ensure sealing performance. This split design significantly reduces the difficulty of loading and unloading internal components, facilitating later maintenance.

2. Positioning and assembly structure: The inner wall of the housing is equipped with specific specification stages to match the outer diameters of different bearings, achieving precise positioning of the bearings.

3. Sealing auxiliary structure: In addition to the sealing rings at the connection points of the housing, some bearing housings that are adapted to the oil lubrication structure will also cooperate with oil boxes, retaining rings and other components to form a closed lubrication cavity, preventing the leakage of lubricating oil and blocking the entry of drilling fluid at the same time, ensuring a stable internal lubrication environment.

III. Material Selection of Bearing Housing

To adapt to the high-temperature, high-pressure and corrosive medium conditions underground, the bearing housing is mostly made of high-strength alloy steel. Some will undergo anti-corrosion and wear-resistant treatment on key contact surfaces such as the inner wall to prevent wear and rust caused by long-term friction with the bearing or contact with drilling fluid.

IV. Common Precautions of Bearing Housing

During assembly, it is necessary to check the fit between the upper and lower shells and the integrity of the sealing ring. If the seal fails, drilling fluid is prone to invade, causing rust and wear of the bearing. It is necessary to ensure that the dimensions of the inner wall step section precisely match those of the bearing. Excessive dimensional deviation may cause the bearing fixation to loosen, leading to component collision and damage. During maintenance, it is necessary to promptly clean the impurities and wear debris on the inner wall of the shell, and at the same time replenish the lubricating medium to ensure the stability of subsequent operations.