초록 ▼

A well tube liner system includes rigid, self supporting plastic liners inserted within well tube sections and including end flanges adjacent opposed ends of the tube sections for sealing against each other and against a connecting collar when the tube sections are drawn axially together during asse

A well tube liner system includes rigid, self supporting plastic liners inserted within well tube sections and including end flanges adjacent opposed ends of the tube sections for sealing against each other and against a connecting collar when the tube sections are drawn axially together during assembly of the tube sections. An auxiliary spacer corresponding in general configuration to the flanges is provided for insertion between the flanges of liner sections to maintain the flanges in axially spaced apart and sealed condition to compensate for worn threads while retaining the same liner sections.

대표청구항 ▼

1. A well tube joint comprising: a first well tube having a first end with an externally threaded tapered portion adjacent the first end, said threaded portion having a minimum external diameter at the first tube first end as measured across the thread crests; a first rigid, self-supporting plas

1. A well tube joint comprising: a first well tube having a first end with an externally threaded tapered portion adjacent the first end, said threaded portion having a minimum external diameter at the first tube first end as measured across the thread crests; a first rigid, self-supporting plastic liner for insertion into the first well tube to extend through the first well tube; a first flange formed of the same plastic material as the first plastic liner attached to the first plastic liner and abutting the first end of the first well tube, the first flange defining a first radial sealing surface and a first unthreaded circumferential sealing surface having an external diameter corresponding to said minimum external diameter of the threaded portion of the first tube first end; a second well tube having a second tube second end with an externally threaded tapered portion adjacent the second end, said threaded portion having a minimum external diameter at the tube second end as measured across the thread crests; a second rigid, self-supporting plastic liner for insertion into the second well tube to extend through the second well tube; a second flange formed of the same plastic material as the second plastic liner attached to the second plastic liner and abutting the second end of the second well tube, the second flange defining a second radial sealing surface and a second unthreaded circumferential sealing surface having an external diameter corresponding to said minimum external diameter of the threaded portion of the second tube second end; the first and second rigid self-supporting plastic liners and said first and second flanges each having the same internal diameter throughout their lengths; a collar having internal threads engaging the threaded portions of the first and second well tubes, said collar internal threads comprising inwardly tapered threads having a minimum internal diameter as measured across the thread crest inside the collar in the central area of the collar; said first and second tube ends, collar and flanges being dimensioned such that upon making up the well tube joint by threading the collar to the first and second tube ends, said flanges sealingly abut each other at their radial sealing surfaces and said circumferential sealing surfaces sealingly engage the internal threads of the collar with said collar threads penetrating the outer circumference of the flanges; and wherein there is provided a smooth constant internal diameter flow path throughout the tubes due to the liners and flanges constant internal diameter. 2. The tube joint according to claim 1, including a plastic annular spacer formed from the same plastic material as the first and second flanges, said annular spacer defining third and fourth radial sealing surfaces at its opposed ends and a third circumferential sealing surface about its circumference, said circumferential sealing surface having an external diameter corresponding to the diameters of the first and second flanges, said spacer located between the first and second flanges; said spacer being dimensioned such that the first and third radial sealing surfaces are in sealing contact, and the second and fourth sealing surfaces are in sealing contact, and the third circumferential sealing surface sealingly engages the interior threads of the collar with said collar threads penetrating the circumference of the spacer when the joint is made up by threading the collar to the first and second tube ends. 3. The tube joint according to claim 2, wherein the radial sealing surface of each of the flanges is of a constant diameter and with a smooth continuous radial surface. 4. The tube joint according to claim 3, wherein the attachment of the flanges to their respective plastic liners is by fusing another radial sealing surface of the flange to a radial end surface of the liner. 5. The tube joint according to claim 2, wherein the attachment of the flanges to their respective plastic liners is by fusing another radial sealing surface of the flange to a radial end surface of the liner. 6. The tube joint according to claim 1, wherein the radial sealing surface of each of the flanges is of a constant diameter and with a smooth continuous radial surface. 7. The tube joint according to claim 6, wherein the attachment of the flanges to their respective plastic liners is by fusing another radial sealing surface of the flange to a radial end surface of the liner. 8. The tube joint according to claims 1, wherein the attachment of the flanges to their respective plastic liners is by fusing another radial sealing surface of the flange to a radial end surface of the liner. 9. A well tube joint comprising: a first well tube having a first end with an externally threaded tapered portion adjacent the first end, said threaded portion having a minimum external diameter at the first tube first end as measured across the thread crests; a first rigid, self-supporting plastic liner for insertion into the first well tube to extend through the first well tube; a first flange formed of the same plastic material as the first plastic liner radially attached to an end of the first plastic liner and abutting the first end of the first well tube, the first flange defining a first radial sealing phase and a first unthreaded circumferential sealing surface having an external diameter corresponding to said minimum external diameter of the threaded portion of the first tube first end; a second well tube having a second tube with an externally threaded tapered portion adjacent the second end, said threaded portion having a minimum external diameter at the tube second end as measured across the thread crests; a second rigid, self-supporting plastic liner for insertion into the second well tube to extend through the second well tube; a second flange formed of the same plastic material as the second plastic liner radially attached to an end of the second plastic liner and abutting the second end of the second well tube, the second flange defining a second radial sealing surface and a second unthreaded circumferential sealing surface having an external diameter corresponding to said minimum external diameter of the threaded portion of the second tube second end; the ends of said plastic liners defining additional radially sealing surfaces; a collar having internal threads engaging the threaded portions of the first and second well tubes, said collar internal threads comprising inwardly tapered threads having a minimum internal diameter as measured across the thread crest inside the collar in the central area of the collar; said first and second tube ends, collar and flanges being dimensioned such that upon making up the well tube joint by threading the collar to the first and second tube ends, said flanges and said ends of said liners sealingly abut each other at their radial sealing surfaces and said circumferential sealing surfaces sealingly engage the internal threads of the collar with said collar threads penetrating the outer circumference of the flanges; and wherein there is provided a smooth constant internal diameter floor path throughout the tubes due to the liners and flanges constant internal diameter. 10. The tube joint according to claim 9, including a plastic annular spacer formed from the same plastic material as the first and second flanges, said annular spacer defining third and fourth radial sealing surfaces at its opposed ends and a third circumferential sealing surface about its circumference, said circumferential sealing surface having an external diameter corresponding to the diameters of the first and second flanges, said spacer located between the first and second flanges; said spacer being dimensioned such that the first and third radial sealing surfaces are in sealing contact, and the second and fourth sealing surfaces are in sealing contact, and the third circumferential sealing surface sealingly engages the interior threads of the collar with said collar threads penetrating the circumference of the spacer when the joint is made up by threading the collar to the first and second tube ends.