Thrust bearing assembly for a downhole drill motor

A thrust bearing assembly for a downhole fluid motor comprising:

• a stationary housing;
• a rotatable shaft extending through the housing;
• a first pair of opposed thrust bearing faces comprising a first stationary thrust bearing face connected to the housing and a first rotatable thrust bearing face connected to the shaft;
• means for transmitting a thrust load in a first direction from the shaft to the first rotatable thrust bearing face and from the first stationary thrust bearing face to the housing;
• a second pair of opposed thrust bearing faces comprising a second stationary thrust bearing face connected to the housing and a second rotatable thrust bearing face connected to the shaft;
• means for transmitting a thrust load in a second direction opposite to the first direction from the shaft to the second rotatable thrust bearing face and from the second stationary thrust bearing face to the housing;
• and wherein
• both means for transmitting comprise spring means for resiliently transmitting thrust between the shaft, bearing faces and housing, the stationary thrust bearing faces are between the rotatable thrust bearing faces, and the spring means resiliently biases the stationary thrust bearing faces apart from each other.

A thrust bearing assembly for a downhole fluid motor comprising:

• a stationary housing;
• a rotatable shaft extending through the housing;
• a first pair of opposed thrust bearing faces comprising a first stationary thrust bearing face connected to the housing and a first rotatable thrust bearing face connected to the shaft;
• means for transmitting a thrust load in a first direction from the shaft to the first rotatable thrust bearing face and from the first stationary thrust bearing face to the housing;
• a second pair of opposed thrust bearing faces comprising a second stationary thrust bearing face connected to the housing and a second rotatable thrust bearing face connected to the shaft;
• means for transmitting a thrust load in a second direction opposite to the first direction from the shaft to the second rotatable thrust bearing face and from the second stationary thrust bearing face to the housing;
• spring means for resiliently biasing both pairs of thrust bearing faces toward engagement;
• and wherein
• the stationary thrust bearing faces are between the rotatable thrust bearing faces and the spring means resiliently biases the stationary thrust bearing faces apart from each other.

A thrust bearing assembly for a downhole motor comprising:

• a stationary housing;
• a rotatable shaft extending through the housing;
• at least one pair of opposed thrust bearing faces comprising a metal substrate and a plurality of inserts embedded in and held by the metal substrate, each insert having polycrystalline diamond at the thrust bearing face;
• the first thrust bearing face having a flat area in a radial plane, the second thrust bearing face having a plurality of sectors, each sector being tilted from a radial plane at an angle of up to a few degrees to facilitate forming a hydrodynamic fluid bearing film with the flat area;
• spring means for resiliently biasing the pair of opposing thrust bearing faces toward face-to-face engagement;
• and
• means for conveying drilling fluid from said motor to the bearing faces during rotation of the shaft for providing a hydrodynamic fluid film in the thrust bearing interface.

A thrust bearing assembly for a downhole motor comprising:

• a stationary housing;
• a rotatable shaft extending through the housing;
• at least one pair of opposed planar thrust bearing faces comprising:
• a ring mounted on the housing and a ring mounted on the shaft, each of said rings comprising a metal substrate and a plurality of inserts embedded in and held by the metal substrate, in each of said rings, said inserts comprising right cylindrical supporting studs of tungsten carbide with flat end faces of polycrystalline diamond laying substantially in a common plane;
• spring means for resiliently biasing the pair of opposing thrust bearing faces toward face-to-face engagement;
• and
• means for conveying drilling fluid from said motor to the bearing faces during rotation of the shaft.

A thrust bearing assembly for a downhole fluid motor comprising:

• a stationary housing;
• a rotatable shaft extending through the housing;
• a lower rotatable thrust bearing ring mounted on the shaft and having an upwardly facing planar thrust bearing face;
• an upper rotatable thrust bearing ring mounted on the shaft and having a downwardly facing planar thrust bearing face;
• a lower stationary thrust bearing ring mounted in the housing and having a downwardly facing planar thrust bearing face in opposing engagement with the lower rotatable thrust bearing face;
• an upper stationary thrust bearing ring mounted in the housing and having an upwardly facing planar thrust bearing face in opposing engagement with the upper rotatable thrust bearing face;
• and
• a plurality of Belleville springs between the upper and lower stationary thrust bearing rings for resiliently biasing the upper thrust bearing faces toward engagement and resiliently biasing the lower thrust bearing faces toward engagement and for transmitting thrust between the upper and lower stationary thrust bearing rings.

A bearing assembly for a downhole fluid motor comprising:

• a stationary housing;
• a rotatable drive shaft extending through the housing;
• means for connecting the housing to the housing of a downhole fluid motor;
• means for connecting one end of the drive shaft to the drive shaft of a downhole fluid motor;
• means for connecting the other end of the drive shaft to a rock bit;
• a radial journal bearing sleeve fixed in the housing;
• a radial journal bearing fixed on the drive shaft within the journal bearing sleeve;
• and
• a bidirectional thrust bearing assembly comprising:
• a first rotatable thrust bearing ring connected to the drive shaft and having a radially extending thrust bearing face;
• a second rotatable thrust bearing ring connected to the drive shaft and having a radially extending thrust face facing in the opposite direction from the thrust face on the first rotatable thrust bearing ring;
• a first stationary thrust bearing ring connected to the housing and having a radially extending thrust bearing face for engaging the thrust bearing face on the first rotatable thrust bearing ring;
• a second stationary thrust bearing ring connected to the housing and having a radially extending thrust bearing face for engaging the thrust bearing face on the second rotatable thrust bearing ring;
• and
• spring means for resiliently biasing the bearing faces on said first thrust bearing rings toward interengagement and for resiliently biasing the bearing faces on said second thrust bearing rings toward interengagement;
• and wherein
• each pair of thrust bearing faces comprise a first thrust bearing face having a flat area in a radial plane and a second thrust bearing face having a plurality of sectors, each sector being tilted from a radial plane at an angle of up to a few degrees for forming a hydrodynamic fluid bearing film with the flat area.

A bearing assembly for a downhole fluid motor comprising:

• a stationary housing;
• a rotatable drive shaft extending through the housing;
• means for connecting the housing to the housing of a downhole fluid motor;
• means for connecting the other end of the drive shaft to a rock bit;
• a radial journal bearing sleeve fixed in the housing;
• and
• a bidirectional thrust bearing assembly comprising:
• a first rotatable thrust bearing ring connected to the drive shaft and having a radially extending thrust bearing face;
• a second rotatable thrust bearing ring connected to the drive shaft and having a radially extending thrust face facing in the opposite direction from the thrust face on the first rotatable thrust bearing ring;
• a first stationary thrust bearing ring connected to the housing and having a radially extending thrust bearing face for engaging the thrust bearing face on the first rotatable thrust bearing ring;
• a second stationary thrust bearing ring connected to the housing and having a radially extending thrust bearing face for engaging the thrust bearing face on the second rotatable thrust bearing ring;
• the bearing faces of said first and second stationary thrust bearing rings being between the bearing faces of the rotatable thrust bearing rings;
• spring means for resiliently biasing the bearing faces on said first thrust bearing rings toward interengagement and for resiliently biasing the bearing faces on said second thrust bearing rings toward interengagement;
• and
• wherein at least a portion of the thrust bearing rings each comprise a metal ring and a bearing member embedded in the metal ring forming the thrust bearing face, the bearing member having a hardness of at least 8 on the Mohs scale.

A thrust bearing assembly for a downhole fluid motor comprising:

• a stationary housing;
• means for connecting the housing to the housing of a downhole fluid motor;
• a rotatable drive shaft extending through the housing;
• means for connecting one end of the drive shaft to the drive shaft of the downhole fluid motor;
• means for connecting a rock bit to the other end of the drive shaft;
• an upper rotatable radial journal bearing sleeve fixed on the shaft;
• an upper rotatable thrust bearing ring on the shaft connected to the upper rotatable journal bearing sleeve for rotation therewith and having a downwardly facing thrust bearing face;
• a lower rotatable radial journal bearing sleeve fixed on the shaft;
• a lower rotatable thrust bearing ring connected to the lower rotatable journal bearing sleeve for rotation therewith and having an upwardly facing thrust bearing face;
• an upper stationary radial journal bearing sleeve in the housing surrounding the upper rotatable radial journal bearing sleeve;
• an upper stationary thrust bearing ring connected to the upper stationary radial journal bearing sleeve, the upper stationary thrust bearing ring having an upwardly facing thrust bearing face opposite the downwardly facing thrust bearing face on the upper rotatable thrust bearing ring;
• a lower stationary radial journal bearing sleeve in the housing surrounding the lower rotatable radial journal bearing sleeve;
• a lower stationary thrust bearing ring connected to the lower stationary radial journal bearing sleeve and having a downwardly facing thrust bearing face opposite the upwardly facing thrust bearing face on the lower rotatable thrust bearing ring;
• means for transmitting torque between the upper stationary thrust bearing ring and the lower stationary thrust bearing ring;
• and
• spring means between the upper stationary thrust bearing ring and lower stationary thrust bearing ring for resiliently biasing said rings apart from each other.

A thrust bearing assembly for a downhole fluid motor comprising:

• a stationary housing;
• means for connecting the housing to the housing of a downhole fluid motor;
• a rotatable drive shaft extending through the housing;
• means for connecting one end of the drive shaft to the drive shaft of the downhole fluid motor;
• means for connecting a rock bit to the other end of the drive shaft;
• an upper rotatable radial journal bearing sleeve fixed on the shaft;
• an upper rotatable thrust bearing ring on the shaft connected to the upper rotatable journal bearing sleeve for rotation therewith and having a downwardly facing thrust bearing face;
• a lower rotatable radial journal bearing sleeve fixed on the shaft;
• a lower rotatable thrust bearing ring connected to the lower rotatable journal bearing sleeve for rotation therewith and having an upwardly facing thrust bearing face;
• an upper stationary radial journal bearing sleeve in the housing surrounding the upper rotatable radial journal bearing sleeve;
• an upper stationary thrust bearing ring connected to the upper stationary radial journal bearing sleeve, the upper stationary thrust bearing ring having an upwardly facing thrust bearing face opposite the downwardly facing thrust bearing face on the upper rotatable thrust bearing ring;
• a lower stationary radial journal bearing sleeve in the housing surrounding the lower rotatable radial journal bearing sleeve;
• a lower stationary thrust bearing ring connected to the lower stationary radial journal bearing sleeve and having a downwardly facing thrust bearing face opposite the upwardly facing thrust bearing face on the lower rotatable thrust bearing ring;
• means for transmitting torque between the upper stationary thrust bearing ring and the lower stationary thrust bearing ring;
• and
• spring means between the upper stationary thrust bearing ring and lower stationary thrust bearing ring and resiliently biasing said rings apart from each other;
• a passage through the drive shaft for conveying drilling fluid from the downhole fluid motor to the rock bit;
• and
• means for bypassing a portion of the drilling fluid from the downhole fluid motor through the interfaces between the opposed radial journal bearing sleeves and between both pairs of opposed thrust bearing faces.

A thrust bearing assembly for a downhole motor comprising:

• a stationary housing;
• a rotatable shaft extending through the housing;
• at least one pair of opposed planar thrust bearing faces comprising a stationary ring mounted on the housing and a rotatable ring mounted on the shaft, each of such rings comprising a metal substrate and an annular bearing face tessellated with triangles of polycrystalline diamond inserted in the metal substrate;
• spring means for resiliently biasing the pair of opposing thrust bearing faces toward face-to-face engagement;
• and
• means for conveying drilling fluid from such a fluid motor to the bearing faces during rotation of the shaft for providing a fluid film in the thrust bearing interfaces.