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starline®HPL-G
Rehabilitation
of Gas Transmission Pipelines up to 30 bar Operating Pressure
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With the starline®HPL-G
CIP (Cured-In-Place) technology, gas transmission pipelines with an operating
pressure up to 30 bar can be relined in individual lengths up to 600 m
in order to restore the required safety standard fast and permanently.
To fulfill the resulting requirements, as materials a seamlessly woven
PLASTIC coated liner made of high-strength yarns in connection with a
special cold-curing epoxy resin into application…. Prior to lining
the pipe, it is shut down and thoroughly cleaned by ultra-high water-jet
system depending on the degree of contamination and roughened up by sand-blasting.
Since the liner's diameter is designed to match the internal diameter
of the pipeline to be rehabilitated, in spite of the high-strength material
a fold-free lining is achieved…. The cold-curing resin system with
a very long pot time excludes the tensions thermally-induced by warm-curing
War in the host pipeline, which especially cause welding-seam fractures
in bitumen-coated transmission pipelines. Once the resin has cured, the
liner is completely and permanently bonded to the host pipe preventing
gas migration and stopping internal corrosion.
The starline®HPL-G technology has been certified
by DVGW VP 404 for a maximum operating pressure of 30 bar. The service
life, verified by 10000-hour time-to-rupture tests is at least 50 years
with a more than twice safety factor to bridge corrosion defects with
a diameter up to 50 mm. Existing and future corrosion fractures, which
pose a special risk for high-pressure gas pipeline are therefore efficiently,
fast and permanently removed using the starline®HPL-G
technology. Thus, the required safety standard is permanently restored
and additionally a minimizing the risk of welding seam fractures.
An economic technology performance is enabled by inspection and rehabilitation
of long pipelien sections for which a completely new and to the specific
requirements designed world-wide unique technology equipment is available.
The entire rehabilitation operation of gas and drinking water transmission
pipelines is based on the basic principle of the proven starline®1000/2000
technologies whereby the following principal changes are:
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- TV inspection with
12-point caliper measurement for documented condition detection and
determine internal diameter or deformations with self-propelled robot
up to 1000 m length. Inadmissible internal diameter deviations are automatically
detected and localized.
- Saturate liner
with the resin via automatic high-power resin mixing and measuring system
with a delivery rate up to 2 to/h and completely new liner application
unit.
- Invert resin-filled
liner into pipeline via special pressure drum for inversion pressure
up to 4. bar with air.
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| Areas
of application: |
| Medium: |
Natural gas and drinking
water |
| Dimension: |
ND 200 - ND 600 (1200) |
| Length: |
individual section
up to 600 m |
| Host pipe: |
welded steel pipe |
| For applications,
such as: |
- actual or potential
corrosion fractures,
- preventive protection
against internal corrosion,
- sealing of culverts,
railroad underpasses and nature reserves, and
- preventive sealing
of fracture-prone welding seams
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the starline®HPL-G
technology restores operational safety. After rehabilitation, the pipeline
can be pressurized with the original operating pressure. Pipes with rust
penetrations of 50 mm diameter remain safe to operate.
Therefore, a relined pipeline is the same as a new pipe and in contrast
to repair methods such as cement mortar lining fully active (after rehabilitation
with the starline®HPL-G fabric-hose relining system
valuable, amortizable performance).
Compared to open-trench construction, excavation works are reduced by more
than 95 %, because contingent on the diameter a construction pit is required
only every 450 to 600 meters.
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