The embodiments discussed herein are merely illustrative of specific manners in which to make and use the invention and are not to be interpreted as limiting the scope of the instant invention.
While the invention has been described with a certain degree of particularity, it is to be noted that many modifications may be made in the details of the invention's construction and the arrangement of its components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification.
The power section includes a portion having a cylindrical housing. The cylindrical housing is typically made of a sturdy metal material. The existing stator is formed within the interior of the cylindrical housing. The existing stator is removed from the cylindrical housing as shown at box 62 in one of a number of ways. The existing stator may be machined or ground out from the cylindrical housing. Alternatively, a chemical agent such as a solvent may be utilized to remove the existing stator from the cylindrical housing 62.
In the event that an existing cylindrical housing is not to be relined, a new cylindrical housing may be used.
Separate from and independent of the removal of the existing stator from the cylindrical housing of the power section, a stator insert is produced. As seen at box 64, a mandrel having a helical exterior surface is inserted into a mold having an internal cylindrical form. The mandrel is inserted into the mold so that the mandrel is coaxial with the mold.
Thereafter, as shown at box 66, a composite stator insert is formed in the mold in the space between the mandrel and the interior cylindrical wall of the mold. Various composite materials may be utilized for the insert. The insert may include fibers, such as carbon fibers, boron fibers, ceramic fibers, glass fibers, thermoplastic fibers, natural fibers, metallic fibers, fibrous resins and synthetic fibers. The composite materials may be infused or impregnated with a resin. These resins include, but are not limited to, alkyl polyesters, general purpose epoxy, general purpose phenolic urea-formaldehyde compositions, polyurethane, silicone, acrylonitrile-butadiene-styrene (ABS), fluoroplastics (PTFE), polyacetal, polyacrylates, polyacrylonitrile (PAN) and polybutadiene (PBD).
The composite stator insert will cure or otherwise form or harden in the mold. Thereafter, the mandrel is removed from the insert as shown at box 68. A smaller diameter second mandrel is then inserted in the mold. As shown at box 70, an inner lining is formed in the space between the outside surface of the second mandrel and the inner surface of insert.
The outer cylindrical surface of the composite insert has a diameter slightly less than the interior diameter of the cylindrical housing of the power section. As seen at box 75, the composite stator insert is then attached to the cylindrical housing of the power section. This may be accomplished in a number of ways. The composite stator insert may be placed in the cylindrical housing and a bonding agent may be injected or otherwise placed between the composite insert and the cylindrical housing. Alternative measures include placing the bonding agent on the outside surface of the insert and then placing the insert into the housing or mechanically connecting the insert to the housing.
Initially, as seen in
The power section 74 includes an external metal cylindrical housing 84 having external threads 86 on each end. The existing helical surface of the stator 88 within the cylindrical housing 84 is removed in a number of ways.
As illustrated in
As a separate procedure, separate and independent from the removal of the existing helical surface of stator 88 from the cylindrical housing 84, a stator insert is formed, as best seen in the sequence of
Thereafter, a fluid material is inserted in the space between the mandrel 94 and the interior wall of the mold 92. The fluid inserted may take many forms including composite materials having fibers such as, but not limited to, carbon fibers, boron fibers, ceramic fibers, glass fibers, thermoplastic fibers, natural fibers, metallic fibers, fibrous resins and synthetic fibers. The composite may also include a resin. The mixture inserted into the mold will harden or cure into a stator insert having a cylindrical exterior and a helical interior.
Thereafter, as shown in
As a final step, the stator insert 100 is inserted and placed back within the cylindrical housing 84 of the power section as best seen in
The present invention to reline a fluid helical device stator may also be accomplished in an alternate, preferred procedure.
Again, as previously described and illustrated in the embodiment in
In the event that an existing cylindrical housing is not to be relined, a new cylindrical housing may be used.
As shown at box 116, a stator insert 108 may be formed from a thin metal cylinder having an outside diameter less than the interior diameter of the cylindrical housing 110. The stator insert 108 has a helical internal surface. The stator insert 108 may be formed in a number of ways, such as metal forming, bending, shaping or other mechanisms which results in a helical internal surface of the metal stator insert.
A lining material 118 is then injected or otherwise applied to the inside surface of the metal stator insert 108 as shown at box 120. Thereafter, the metal insert 108 and lining is inserted into the cylindrical housing 110 of the power section and axially centered in the cylindrical housing 110 as shown in
Whereas, the present invention has been described in relation to the drawings attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the spirit and scope of this invention.