The Spherical stabilizer is an important tool to control hole deviation when drilling a horizontal well or a deflecting well. The stabilizer can prevent from stucking in drilling and improve the quality of well and speed of drilling, which decrease the cost of drilling.Because of small size, simple structure, it is so applicable for horizontal and directional well. The guide inclined plane covered with polycrystalline compact and cutting edges covered with spherical tungsten carbide stud, during stabilizer contacts with roughed hole wall, can cut or scraped off raised or irregular well wall, therefore, the spherical stabilizers are widely used in various of drilling operation.

Construction

The structure of spherical stabilizer as figure, the axial direction of the middle face of stabilizer is shorter, like ball, so call it spherical ball.

There are four kinds of abrasive resistant materials on the working surface of stabilizer.

(1) Insert tungsten carbide buttons on the surface.

(2) Insert diamond compound body on the surface.

(3) Low temperature welding tungsten carbide pieces.

(4) Hardfacing electrode on the surface.

Type	Working O.D.(in)	Body O.D. (mm)	I.D (mm)	Length (mm)	Connection
					String		Near bit
					Top	Down	Top	Down
WQ152	6″	121	51	785	NC38	NC38	NC38	3-1/2REG
WQ159	6-1/4″
WQ165	6-1/2″
WQ191	7-1/2″	159	51 71	850	NC46 NC50	NC46 NC50	NC46 NC50	4-1/2REG
WQ200	7-7/8″
WQ213	8-3/8″	165	51 71	850	NC46 NC50	NC46 NC50	NC46 NC50	4-1/2REG
WQ216	8-1/2″
WQ222	8-3/4″
WQ241	9-1/2″	197	71	870	NC50	NC50	NC50	4-1/2REG
WQ245	9-5/8″
WQ251	9-7/8″
WQ311	12-1/4″	203	71	940	NC56 NC61	NC56 NC61	NC56 NC61	6-5/8REG7-5/8REG
WQ445	17-1/2″	228 241	76	940	NC61	NC61	NC61	7-5/8REG
WQ660	26″				6-5/8REG 7-5/8REG	6-5/8REG 7-5/8REG	6-5/8REG	7-5/8REG