WPCT Shrink Sleeve Installation
Wraparound Pipe Sleeve with Permanent Thermal Indicator for Field Girthweld Corrosion Protection.
WPCT heat-shrinkable wraparound sleeves are designed for corrosion protection of girthwelds on buried pipelines.
WPCT sleeves have a thick radiation-crosslinked polyolefin backing coated with a specially formulated mastic sealant. During installation the mastic flows and fills surface irregularities, bonding to metal and adjacent coating surfaces. The flexible closure is coated with a high shear-strength adhesive and is kitted with the sleeve; it is available pre-attached to the sleeve in the UNISLEEVE construction.
Simple Installation Resists adverse environments
To install, wrap the sleeve around a clean, WPCT sleeves resist hydrostatic pressure.
preheated pipe. A flexible closure forms the They demonstrate high resistance to
sleeve into a tube. The sleeve is then torch- ultraviolet light, fungus, bacteria, cathodic
shrunk around the pipe. disbondment and chemical attack by
The WPCT sheet is embossed with a pattern common fluids and solvents.
showing "Raychem MORE HEAT" that
becomes smooth when sufficient heat has Versatile
been supplied. The permanent change in WPCT sleeves are compatible with all
the pattern facilitates proper installation and standard pipe coatings and outer jackets,
inspection. including fusion-bonded epoxy, polyethylene,
tape and coal tar. the product has a long
Rugged and mechanically strong shelf-life when stored correctly at
WPCT sleeves resist abrasion, impact and temperatures below 50 degrees C.
penetration. No rock-shield is Required.
Materials and equipment
- Appropriate size WPCT sleeve and WPCP IV closure patch
- Raychem torch (or equivalent)
- Propane gas tank, hose, regulator and gauge
- Standard safety equipment such as gloves, goggles, hard hat, etc.
1. Clean exposed steel and adjacent pipe
coating to be covered by WPCT sleeve with a
hand or power wire brush, to remove loose
and foreign materials. Wiping may be
necessary to remove the particles from
Coal tar - remove outer paper wrap 5" (125
mm) to 6" (150 mm) adjacent to cut-back to
expose coal tar.
Painted coatings - remove whitewash paint
on the surface of coating to be covered by
2. The pipe shall be preheated until approximately
140 degrees F (60 degrees C) minimum and check for
conformance either by temperature gauge or other temperature
measuring device. Preheating reduces installation time
and ensures proper bonding.
Two people working on opposite sides of
the pipe are recommended for installing
sleeves on pipe 16" (400 mm) in diameter
3. Remove the protective release plastic from the
coated sleeve. Center sleeve over the weld so it is
evenly overlapping adjacent pipe coating. Wrap
loosely around pipe so that the Raychem logo runs
around the pipe.
1) Clean over lap area of the sleeve to remove
dirt and other foreign material.
2) Edges of sleeve should extend 2" or more
onto adjacent pipe coating.
3) Overlapping ends of sleeve should align evenly.
4)Position overlap to permit easy access for installing closure.
WPCP IV Closure Application
1. Press WPCPIV closure in position, centering over the exposed
sheet end.(For UNISLEEVE products, the closure is pre-attached
and already centered in position.)The sheet should overlap the
sheet (excluding closure) by 2" (50 mm) minimum.
2. Using a Raychem torch (or equivalent), adjust flame length to
approximately 20" (500 mm) to produce a blue tipped yellow
flame.Using the yellow portion of the flame, heat the closure
evenly until the pattern of the fabric reinforcement is visible.
With gloved hand, smooth any wrinkles by working outward from the center.
1. Using the Raychem torch (or equivalent),
begin at the center of the sleeve and heat
circumferentially around the pipe using a
constant paintbrush motion, until the
embossed pattern on the sheet surface has
changed to a smooth surface.
2. Continue heating toward one end of the
sleeve, followed by the other.
Sleeve may be recovered starting at one end
and proceeding toward the opposite end,
depending on conditions (i.e., wind).
3. During shrinkdown, occasionally check
adhesive flow with a finger. Wrinkles should
disappear automatically. Remember to wear
While sleeve is hot, press roll overlap and
closure area to remove any air voids.
4. Sleeve is fully recovered when all of the
following have occured:
1) The WPCT sheet has a smooth surface.
2) There are no cold spots on the sleeve surface.
3) Weld bead profile can be seen through the sleeve
4) After sleeve is cool, mastic flow is evident
on both edges.
5) The sleeve has fully conformed to
pipe and adjacent coating.
6) The pattern on the backing has disappeared and the backing has a smooth surface.