Sleeving

SLEEVING

SLEEVE INSTALLATION

Tubes should be clean from all debris and the tube
ends free of dings, weld spatter, ect. The parent tube is
prepared for sleeve installation – measurements are
reconfirmed as correct on the parent tube I.D. surface
and sleeve. A sleeve is installed onto the sleeving tube
– Expansion pressure is brought to 2000 PSIG to lock
sleeve on installation tooling. The sleeve is installed
into the parent tube section and set to the
predetermined position (Flush or protruded). The
sleeve is raised to its expansion/yield pressure where
the stress pressure begins to yield the tube and reacts
in a fully elastic condition. The sleeve is brought to its
interference pressure (IP). The sleeve is held as it’s IP
for a predetermined time (Dwell Time) during which
there is elastic material recovery (Spring back). The
pressures are released and installation tool removed.
The flared sleeve end is rolled into the parent tube (Soft
Roll). The straight sleeve end is expanded to the tube
parent tube.

NOMENCLATURE

Load pressure – 2000 PSIG
Yield Pressure – Calculated and field tuned
(8000 PSIG - .750 X .030 wall – 316l Stainless Steel)
Interference fit pressure - Yield pressure + 1000 PSIG
Tube O.D. – (Eg – .1” O.D.)
Tube I.D. – (Eg. – .782 I.D.)
Tube wall Thickness – (Eg. - .109)
Tube Material – (Eg. – SA-178)
Sleeve O.D. – (Eg. – .593” O.D.)
Sleeve I.D. – (Eg. – .495” I.D.)
Sleeve wall thickness – (Eg. – .049”)
Sleeve Material – 316 L Stainless steel)

PROCEDURE for HYDRO-EXPANSION

View of Finfan being sleeved due to
severe inlet thinning
– Sleeve length 2’

View of process gas cooler in
sleeving process
– Sleeve length 3’

Full length sleeve expansion
921 tubes completed in 27 hours

Correct design information is required to insure a high strength sleeve to tube joint
by the use of hydro-expansion techniques. The frictional interference fit between the
installed sleeve and the parent tube produced by hydro-expansion is governed by
many variables. These variables are listed below.

It should be noted that specific tube heats may vary the expansion to a great degree.
Calculated and actual expansion pressures might be different and the calculated
pressure is meant as a guide line for installation. Determination of the actual field
installing pressure are to be determined by calculated and field tuned pressures that
yield the proper fit.

Sleeve expansion develops interference fit pressure that expands the sleeve for its
entire length within the parent tube. The appropriate calculation’s for specific
material yields, material compatibility, and sleeve installation pressure are reviewed
prior to sleeve installation to insure proper fit. Expansions of the sleeve test coupons
are shown to have wall reductions of between 2% and 5%. These wall reductions are
approximately 1/3rd to 1/2 of the wall reductions found in hard rolled tubes.

Thorough review of corrosion mechanism, location and extent allow for the sleeving
of tubular process equipment to be fully effective. The correct sleeve metallurgy
being selected, the sleeve being positioned within the corrosion area and the correct
sleeve length to cover the corrosion area must all be considered when planning a
sleeve operation.

Conditional analysis of heat transfer tubing is a major concern due to budgeted
funding, repair, retube, and or modification of your heat transfer equipment to return
it to 100 percent capacity. For this reason a comprehensive Eddy Current inspection
should be performed to allow your plant personnel to make wise decision's
concerning tubular equipment.