Note: Descriptions are shown in the official language in which they were submitted.
~Z35~
WELDLl~SS HIGH PRESSURE PIPE FITTING
The present invention relates to high-pressure pipe
fittings, and particularly to those which may be installed
without the use of heat or open flame.
BACKGROUND OF THE INVENTION
It is frequently necessary Jo make repairs to rut-
lured or leaking high pressure pipes in areas of extreme
explosion or fire hazard, such as the engine rooms of ships
or refineries. Typical repairs consist of replacing a de-
fictive section of pipe with a new section either by direct-
lye welding the new section in place or by bolting expansion
joints between welded flanges at both ends of the new sea-
lion and welded flanges at the open ends of the pipeline
where the damaged section was removed. In either case,
on-site welding is necessary, and the areas to be worked
must be freed of all flammable gases and liquids. For
welding operations in new ships or new refineries, it is
usually neither difficult nor costly to comply with this
mandate. ivory, the process of "gas freeing" the engine
room of an operating ship or a particular sector of a no-
finery is normally a costly and lengthy process.
It would be highly advantageous to be able to
effect the reliable flanging or coupling of large diameter,
high pressure pipes without the use of heat or flame.
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Flexible couplings for joining plain-end tubes or pipes are
available from several manufacturers Typically, these
couplings comprise a tubular housing into which a tube or
pipe is inserted at either end. Circular resilient seals
are then clamped to seal the gaps between -the housing and
the tubes or pipes. Although a joint made with this type of
coupling lacks the reliability and durability of a welded
joint or an expansion joint between two welded flanges, it
does have the advantage of simplicity of installation
without the use of heat or flame.
A search made by the applicant for prior art relet-
Ed to the invention has revealed numerous pipe fittings and
connectors. U.S. Patent No. 2,011,433, issued to Gabriel E.
Bragg on March 25, 1933 teaches the construction of a pipe
coupling especially useful for joining sections of thin-wall
tubing. Although complementary frusto-conical surfaces are
used to secure a tight joint without the use or gaskets or
packing, the joint necessarily reduces the inside diameter
of the line and also deforms the ends of the sections of
tubing to be joined. U.S. Patents 1,821,863 and 1,821,865,
both issued to Wylie G. Wilson on September 1, 1931~ teach
the use of a tapered seal to provide fluid tight joints.
However, the method requires that the ends of the pipes to
be joined be fitted with specially designed flanges, which
presumably must be welded to the ends of the pipes. U.S.
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Patent No. 3,749,426, issued to Cassius Till man on July 31,
1973, teaches the use ox a pipe joint seal in the form of a
tubular member having beveled ends, which is compressed
between the recesses of aligned flanged pipes connected
together under stressed conditions, such as with bolts,
studs or clamps. Once again, however, the special flange
must be welded to the ends of the pipes to be joined. There
is a very real commercial need for a pipe fitting which can
be tightly secured to the end of a rigid wall, high pressure
pipe so that it may be flanged or coupled without the use of
welding.
SUMMARY OF THE I~V~TION
The primary objective of this invention is to pro-
vise a means for flanging and coupling high pressure, rigid
wall pipes without the use of heat or flame so that the
flanging or coupling process may be carried out under conduit-
ions where "gas freeing" would be essential were welding
used in the operation.
A secondary objective of the present invention is
to provide a pipe fitting which neither visibly deforms nor
reduces the inside diameter of the pipeline.
The present invention may be used to flange or
couple rigid wall pipes of any diameter. On a three inch
pipe, the fitting has been tested to withstand pressures of
372 kegs per cm .
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BRIEF DESCRIPTION OF TOME DRAWINGS
FIG. 1 is a cross-sectional view of a pair of ides-
tidal connector flange assemblies, each of which incorpor-
ales the weedless high pressure fitting, connected by means
of a commercially available expansion joint, the outline of
which is shown by broken lines:
ERG. 2 is a view taken along line 2-2 showing the
entire connector flange assembly mounted on a pipe;
FIG. 3 is a second embodiment of the invention
showing the joining of two pipes by means of a coupling
which incorporates two of the weedless high pressure
fittings;
FIG. 4 is a view taken along line 4-4 showing the
entire circular locking flange with a circular recess.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, two sections of pipe 11
and 12 are shown connected by means of a commercially avail-
able expansion joint bolted to a pair of connector flange
assemblies constructed in accordance with the present invent
lion. Circular locking flange 13 has an inside diameter
closely sized to enable it to slide over the end of pipe 11
without galling. Locking flange 13 has a first series of
holes 14 arranged in a radial pattern. The tubular deform-
able locking sleeve 15 has an inside diameter closely sized
12~ 3~7
to enable it to slide over the end ox pipe 11 without gall-
in. The outer surface of the locking sleeve tapers to form
a frusto-conical section. The locking sleeve 15 is mounted
on the pipe 11 so that the thickest edge of the sleeve faces
locking flange 13. A rigid collar 16 incorporating a con-
nectar flange 17 has a tapered frusto-conical inner surface
which mates with the frusto-conical outer surface of the
locking sleeve 15 when the collar 16 is slid over the end of
the pipe 11. The collar 16 has a second series of threaded
holes 18 arranged in a circular pattern identical to the
hole pattern of locking flange 13. The thickest edge of
locking sleeve 15 annularly protrudes from the collar. When
locking flange 13 is bolted against the collar 16 by means
of a series of bolts 19, each of which is inserted through a
hole 14 and tightened in a threaded hole 18, the annularly
protruding edge of sealing sleeve 15 is forced deeper into
the tapered recess formed by the outer surface of the pipe
11 and the tapered inner surface of the collar 16, locking
and sealing collar 16 in a fixed position on pipe 11. The
amount which sealing sleeve 15 is forced into the tapered
recess is determined by the thickness of a circular shim 21
which is placed between the locking flange 13 and the collar
16. The shim 21 fits into the circular recess 22 in locking
flange 13.
SLY
Referring now to FIG. 3, two sections of pipe are
shown connected by means of a coupling constructed in act
cordons with the present invention. The locking flanges
13, sealing sleeves 15, shims 21, first series of holes 14
and second series of holes 18 are identical to those of FIG.
1 for pipes having identical diameters. In FIG. 1, two
collars 16 are portrayed, each incorporating a connector
flange 17. In FIG. 3, the double flanged collars are no-
placed by a single collar 31 which bridges both sections of
pipe 11 and 12.
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