Patent Publication Number: US-9885363-B2

Title: Cap for submersible pump

Description:
REFERENCE TO RELATED APPLICATIONS 
     The current application claims priority to PCT application No. PCT/RU2012/000718 filed on Aug. 30, 2012, which claims priority to Russian application No. RU 2012127091 filed on Jun. 28, 2012. 
     FIELD OF THE INVENTION 
     The utility model relates to pipeline equipment for water supply and to oil and gas industry, namely, to auxiliary equipment of submersible pumps. 
     The cap is intended for suspension of submersible pump with pressure pipe and cable. 
     PRIOR ART 
     There is a known cap for suspension of submersible pump with a pressure pipe and a cable comprising a cover with conical surface and a central axial hole, and a clamping flange with a central axial hole installed on the well casing coaxially, a sealing rubber ring located between the conical surface of the cover and the flange, a set of coupling bolts with nuts installed in the coaxial holes of the cover and the flange (SU No 1105581). 
     The shortcoming of the known cap lies in the fact that the sealing rubber ring and the set of coupling bolts with nuts are located on the inner side of the casing pipe, which leads to an increase of the diameter of the casing pipe and a decrease of its effectively used through cross-section. 
     Also known is a cap for suspension of submersible pump with a pressure pipe and a cable comprising a cover with conical surface and a central axial hole, and a clamping flange with a central axial hole installed on the well casing coaxially, a sealing rubber ring located between the conical surface of the cover and the flange, a set of coupling bolts with nuts installed in the coaxial holes of the cover and the flange, where on the butt end of the cover facing the flange, along its circumference, there is a circular collar with inner conical surface, the vertex of its cone facing the side opposite to the flange, while the clamping flange and the sealing rubber ring are installed on the outer side of the casing pipe, where the axial holes in the cover and the flange are also made on the outer side of the casing pipe (RU No 76033, prototype). 
     The shortcoming of the known device is its low reliability and durability not providing repeated use of the article, which are determined by possible cutting of the edge of the flange hole into the rubber ring and the latter&#39;s being insufficiently pressed against the casing pipe. 
     SUMMARY OF THE INVENTIONS 
     The engineering target of the claimed utility model is to create an efficient cap for suspension of submersible pump with a pressure pipe and a cable. As well as to expand the range of cap models for suspension of submersible pump with a pressure pipe and a cable. 
     The technical result providing solution of the assigned target lies in raising the reliability and durability that provides repeated use of the article determined by eliminating the possibility of cutting of the edge of the flange hole into the rubber ring owing to guaranteed displacement of the edge of the flange hole away from the surface of contact between the flange and the rubber ring, and the latter&#39;s being pressed stronger against the casing pipe owing to making the direction of the ring&#39;s pressing against the pipe closer to being radial. 
     The essence of the utility model is that the cap comprises a cover with a central hole and a circular collar made in the conical inner surface form narrowing towards the central hole, as well as a clamping flange with a central hole, a rubber ring to be installed on the casing pipe between the conical surface of the cover collar and the flat side of the flange, and coupling threaded elements for fixing the rubber ring between the cover and the flange, where the central hole of the clamping flange is made with a diameter smaller than the mean diameter of the rubber ring, while the smaller diameter of the conical surface of the cover collar is made exceeding the mean diameter of the rubber ring. 
     In particular embodiments, the cover and the flange are made of metal, where the flange is made with a cylindrical collar on the side opposite to the side of installation of the rubber ring. 
     In other particular embodiments, the cover and the flange are made of plastic, where the flange is made with cylindrical and straight radial stiffening ribs on the side opposite to the side of installation of the rubber ring, and the ring is made with cylindrical and straight radial stiffening ribs on the side of installation of the rubber ring. 
     Preferably, the cover is provided with a collet clamp for the pressure pipe of the pump, the aforesaid collet clamp installed in the central axial hole of the cover, the cover is provided with at least one cable entry, the cover is provided with upper and lower eyebolts, where all the eyebolts are located in the same centerline plane. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The  FIG. 1  presents a general exploded view of a well cap for suspension of submersible pump with a pressure pipe and a cable, 
         FIG. 2  presents a cutaway view of installation of the cap onto a casing pipe, and 
         FIG. 3  presents a cutaway view of installation of a plastic cap onto a casing pipe. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Preferred Embodiment 
     The well cap for suspension of submersible pump with a pressure pipe and a cable comprises cover  2  with central axial hole  4  for passage of pressure pipe  22  and with circular collar  10  made with cylindrical outer surface and conical inner surface  3  narrowing towards central hole  4 , as well as cylindrical flange  5  with central hole  17 , sealing rubber ring  6  of round section to be installed onto casing pipe  1  between conical surface  3  of collar  10  of cover  2  and flat side  18  of flange  5 . The coupling threaded elements—bolts  7  with nuts  8  are installed in coaxial holes  9  of cover  2  and flange  5  for fixation of rubber ring  6  with its inner diameter on outer surface of pipe  1  between cover  2  and flange  5 . Central hole  17  of clamping flange  5  is made with diameter D 1  smaller than mean diameter D m  of rubber ring  6 , while smaller diameter D 2  of conical surface  3  of collar  10  of cover  2 , exceeding mean diameter D m , which is equal to the half sum of the outer and inner diameters of rubber ring  6 . 
     Cover  2  is provided with collet clamp  11  for pressure pipe  22 , the aforesaid collet clamp installed in central axial hole  4  of cover  2 . Cover  2  is also provided with cable entry  12 . 
     In particular embodiments, cover  2  and flange  5  may be made of metal (cast iron), where flange  5  is made with cylindrical collar  19  on the side opposite to the side of installation of rubber ring  6 , while hole  4  is made a thread for collet clamp  11 . 
     In other particular embodiments, cover  2  and flange  5  may be made of plastic. In this case, collet clamp  11  may be made partially (with its fixed part) integral with cover  2 , where hole  4  (for pipe  22 ) of cover  2  is at the same time a hole of the fixed part of collet clamp  11  made integral therewith. Here, flange  5  is made of cellular design, i.e., with cylindrical and straight stiffening ribs  21  on the side opposite to the side of installation of rubber ring  6 , while cover  2  is also made of cellular design, i.e., with cylindrical and straight radial stiffening ribs  20  around collar  10 , on the side of installation of rubber ring  6 . 
     In any case, cover  2  is provided with upper eyebolts  13  and lower eyebolt  14  with sealing cap locknut  15  and suspended clevis  16  for fastening of a rope for suspension of submersible pump (not shown). All eyebolts  13 ,  14  are located in the same centerline plane, where the vertical axis of the cover and the flange lies. 
     Coaxial holes  9  in cover  2  and flange  5  are made around collar  10  and, hence, on the outer side of casing pipe  1 . 
     The well cap for suspension of submersible pump with a pressure pipe and a cable is operated as follows. 
     For putting in operation, prior to suspending a submersible pump with a pressure pipe and a cable, it is necessary to cut casing pipe thoroughly at right angle to its axis, which is rather difficult to do in field conditions. Then burrs are removed at the cut, casing pipe  1  is trimmed up from outside, primed and coated with corrosion-proof paint. The submersible pump is prepared for submersion according the pump manual, which includes connecting plastic pipe to the pump fitting, attaching a rope of required length to the pump housing and extending the control cable. 
     Next, the free part of the rope is attached to clevis  16 . Clevis  16  is engaged with lower eyebolt  14 , after the plastic pressure pipe has been threaded through collet clamp  11 , and the cables have been threaded through cable entries  12  of cover  2 . Flange  5  is put, with its flat side (surface)  18  upwards, jointly with rubber ring  6 , onto casing pipe  1 . The pipe is lowered, whereupon cover  2  is put onto casing pipe  1 . Then, rubber ring  6  and flange  5  are raised up to the contact of ring  6  with conical surface  3  of cover  2 . Bolts  7  and nuts  8  are used for drawing together flange  5  and cover  2 , while contracting rubber ring  6  placed in-between. 
     Hermetic sealing of the pump in pipe  1  is achieved through tightening of bolts  7  contracting sealing rubber ring  6 , which is located between cover  2  and clamping flange  5 . Conical surface  3 , when clamped with bolts  7  of cover  2  with flange  5 , exercises clamping of rubber ring  6  around pipe  1 . To prevent the pressure pipe of the pump from sagging, the pipe is tightening and clamped with collet clamp  11 . 
     At the same time, assembling requires no welding operations; the pump is lowered with a winch, crane, or other hoisting mechanisms by upper eyebolts  13  mounted in cover  2 . 
     As central hole  17  of clamping flange  5  is made with diameter D 1 , which is guaranteed to be smaller than mean diameter D cp  of rubber ring  6 , the possibility for the edge of hole  17  of flange  5  into rubber ring  6  is eliminated owing to guaranteed displacement of the edge of hole  17  of flange  5  to pipe  1  from the surface of contact of flange  5  with rubber ring  6  and a larger area of the latter&#39;s contact with side  18  of flange  5 . 
     As smaller diameter D 2  of conical surface  3  of collar  10  of cover  2  is guaranteed to be made exceeding mean diameter D m  of rubber ring  6 , the force pressing the latter against pipe  1  is guaranteed to increase owing to the fact that the direction of the ring&#39;s being pressed against pipe  1  is made closer to being radial and hence, the component normal to surfaces of pipe  1 , of ring  6  is increased, as well as the area of contact of the same that provides hermetic sealing and reliability of the joint. At the same time increased reliability and durability are provided that is determined by elimination of the possibility for the edge of the flange to cut into the rubber ring owing to guaranteed displacement of the edge of the flange hole from the surface of contact of the flange with the rubber ring. 
     According to its designated purpose, this structure safely prevents the pipe and the submersible pump from penetration of surface ground waters and foreign objects, protects the pump and the pipe from unauthorized access, increases reliability and durability of the article, and provides repeated use of the rubber ring. 
     INDUSTRIAL APPLICATIONS 
     The present invention is embodied with multipurpose equipment extensively employed by the industry.