High pressure sightglass for fluid flow tube

Claim 2

A sightglass for use in a sightglass assembly for a fluid flow tube comprising a substantially transparent sightglass tube having a substantially centered axial cylindrical sightglass bore passing therethrough, said sightglass tube having an outer tube surface and opposite tube end surfaces, each of said end surfaces being spherically configured, said outer tube surface including two substantially parallel flat viewport surface areas positioned on respectively opposite sides of said sightglass tube.

Claim 3

The sightglass defined in claim 1 wherein said outer tube surface is substantially cylindrical and truncated by said viewpoint surfaces.

Claim 4

The sightglass defined in claim 2 wherein said sightglass tube has a wall thickness substantially over the length of said outer tube surface at least as great as the diameter of said sightglass bore.

Claim 5

The sightglass defined in claim 3 wherein said bore of said sightglass tube has a length not greater than substantially twice its diameter, and wherein said substantially cylindrical outer tube surface has an axial length substantially equal to the diameter of said bore.

Claim 6

A sightglass assembly for a fluid flow tube comprising: a substantially transparent sightglass tube having a substantially centered axial cylindrical sightglass bore passing therethrough, said sightglass tube having an outer tube surface and opposite tube end surfaces, each of said end surfaces being tapered, said outer tube surface having an area adapted optically for viewing said bore through the wall of said sightglass tube; two sightglass assembly endpieces, each endpiece having an axial endpiece fluid flow bore of a diameter substantially equal to the diameter of said sightglass bore, each endpiece having a recessed sightglass end receiving surface in which the endpiece fluid flow bore is centered, said receiving surfaces of said endpieces being conformed to the respective tapered sightglass tube end surfaces for mated compressional fitting of said sightglass tube between said end pieces in coaxial alignment; and, means for fixedly clamping said sightglass tube in axial compression between said endpieces with said end piece bores coaxially aligned with said sightglass tube bore, and with said tapered tube end surfaces cooperably abutting against said receiving surfaces of said endpieces, thereby converting a portion of the axial compressional stress in said tube into radially inwardly directed precompression thereof.

Claim 7

A sightglass assembly for a fluid flow tube comprising: a substantially transparent sightglass tube having a substantially centered axial cylindrical sightglass bore passing therethrough, said sightglass tube having an outer tube surface and opposite tube end surfaces, each of said end surfaces being tapered, said outer tube surface having an area adapted optically for viewing said bore through the wall of said sightglass tube; two sightglass assembly endpieces, each endpiece having an axial endpiece fluid flow bore of a diameter substantially equal to the diameter of said sightglass bore, each endpiece having a recessed sightglass end receiving surface in which the endpiece fluid flow bore is centered, said receiving surfaces of said endpieces being conformed to the respective tapered sightglass tube end surfaces for mated compressional fitting of said sightglass tube between said end pieces in coaxial alignment; and, means for fixedly clamping said sightglass tube in axial compression between said endpieces with said end piece bores coaxially aligned with said sightglass tube bore, and with said tapered tube end surfaces cooperably abutting against said receiving surfaces of said endpieces, thereby converting a portion of the axial compressional stress in said tube into radially inwardly directed precompression thereof.

Claim 8

The sightglass assembly defined in claim 5 wherein said tapered tube end surfaces and said recessed endpiece receiving surfaces are spherically configured.

Claim 9

The sightglass assembly of claim 6 wherein said outer tube surface includes two substantially parallel flat viewport surface areas positioned opposite one another on said outer tube surface.

Claim 10

The sightglass assembly of claim 7 wherein said outer tube surface is substantially cylindrical and truncated by said viewport surfaces.

Claim 11

The sightglass assembly of claim 8 wherein said sightglass tube has a wall thickness substantially over the length of said outer tube surface at least as great as the diameter of said sightglass bore.

Claim 12

The sightglass assembly of claim 9 wherein said bore of said sightglass tube has a length not greater than substantially twice its diameter.

Claim 13

The sightglass assembly of claim 10 wherein said substantially cylindrical outer tube surface has an axial length substantially equal to the diameter of said sightglass bore.

Claim 14

The sightglass assembly of claim 11 further comprising an elastically deformable sealing means interposed between said tube end surfaces and said endpiece receiving surfaces for providing a fluid-impermeable seal and for more uniformly converting said axial compressional stress in said tube into radially inwardly directed precompression thereof.

Claim 15

The sightglass assembly of claim 12 wherein said elastically deformable sealing means is polytetraflouroethylene.

Claim 16

The sightglass assembly of claim 13 further comprising a removable protective casing positioned around said endpieces and said sightglass tube, said protective casing having two viewports alignable with said viewport surfaces of said sightglass tube.

Claim 17

The sightglass assembly of claim 14 wherein said means for clamping said sightglass tube between said endpieces comprises a plurality of bolt means connecting said endpieces to one another, said bolt means being aligned parallel to one another and to the longitudinal axes of said sightglass bore and said endpiece bores, said bolt means being radially spaced from said sightglass tube and circumferentially spaced from one another around said sightglass tube, said bolt means bearing upon said endpieces with a uniform predetermined tensile load.