What does Three-Layer Extruded Polyethylene Coating (3LPE) mean?
Three-layer polyethylene (3LPE) is a multi-layer coating consisting
of three functional components: a high performance fused epoxy
(FBE) primer followed by a copolymer binder and an outer
polyethylene to provide tough, durable protection. The 3LPE system
provides good pipe protection for small and large diameter pipes
operating at medium and high temperatures.
- Bonding agent or copolymer layer
- Epoxy layer
- Polypropylene or polyethylene layer
Three-Layer Extruded Polyethylene Coating (3LPE)
A three-layer extruded polyethylene coating is used for various
types of pipelines including sewer systems, water pipelines, gas
pipelines and other channels that are dangerous to water.
Polyethylene coatings have been in use to protect buried pipelines
from corroding since the 1950s. This type of coating provides
higher resistance to insulation than bitumen coatings.
A three-layer extruded polyethylene coating can be applied through
sight extrusion and sleeve extrusion. These two methods of applying
polyethylene coating were introduced in the 1960s, replacing the
sintering technique. It was in the 1980s when 3LPE became very
prevalent in the industry.
One advantage of this coating material is that it is
ultra-adhesive, even at room temperature. Also, it can be easily
cut back as necessary by having the pipelines heated. Furthermore,
this material has a very strong chemical resistance that makes it
applicable even in the most aggressive environments, including all
forms of soil.
The chemical resistance of this coating prevents its corrosion.
However, it should be noted that just like many materials, it is
also prone to some types of corrosion. Due to this, as early as
1974, testing has been required to determine the aging or corrosion
resistance of 3LPE. This is conducted by measuring the temperature
with the use of a thermometer at 140°F (60°C). The measure of aging
is the melt index, which is set at an initial value of 25%. Over
the years, more advanced testing methods have been developed to
determine the 3LPE's aging and resistance to corrosion.
The FBE components provide excellent steel adhesion, excellent
long-term corrosion resistance and pipeline protection at moderate
Low application temperature (LAT) FBE may be selected as primer if
desired to ensure low preheat conditions and long term integrity of
high strength steel (X80 or higher).
In addition, the 3LPE system has excellent anti-cathodic stripping
performance, reducing the life cycle cost of cathodic protection.
Advanced manufacturing technology allows you to customize the 3LPE
system for your specific project.
Good mechanical protection
The rugged outer PE layer protects the pipe during transportation
and installation, reducing costly maintenance costs while providing
additional ground protection against shear forces, chemicals and
abrasive soil conditions.
By increasing the thickness of the polyethylene coating, the 3LPE
system can provide a high level of mechanical protection in
difficult environments without the need for expensive backfilling
Can be produced in a single plant or coating plants to improve
With our extensive global footprint, customers can benefit from the
management of a single point of contact project, even in the most
demanding logistics configurations.
Triple polyvinyl coated pipe is the first choice for global oil and
gas transmission. It can withstand a variety of temperatures and
environments, from dessert to dry land to deep water. 3LPE coated
steel tubes are used to transport drinking water, oil, gas and
other fluids. 3 lpe coating tube can be as high as 60 ℃ to 80 ℃
high temperature use.
3LPE coated pipe features:
1. Excellent chemical corrosion resistance to prevent steel pipe
2. Cathodic stripping
3. The polyethylene coating prevents any physical damage to the
pipe or bonded epoxy during handling.
4. 3LPE coated tubes are characterized by high performance and long
|Min pipe diameter||51 mm (2")|
|Max pipe diameter||3620 mm +|
|Min handling construction temperature||-40°C|
|Max recommended operating temperature||85°C|
Natural gas pipeline
Small straight pipe
Water supply system pipeline
Big dia.steel pipe
3 lpe coated pipe
Three-layer polyethylene coated pipeline is the world's preferred
oil and gas pipeline. It can withstand a variety of temperatures
and environments, from desert arid lands to the deep ocean. The
3LPE coated steel tube is used for the transportation of drinking
water, oil, natural gas and other fluids. 3LPE coated tubes can be
used at 60o - 80oc.
Features of 3LPE coated tubes:
1. Excellent chemical corrosion resistance to prevent steel tube
2. Cathodic stripping resistance
3. The outer layer of polyethylene prevents any physical damage to
the pipe or fused epoxy during the process
4. 3LPE coated tubes have high performance and long service life
3LPE pipe coating equipment supplier in China
HYAL Ltd. is a pioneer in supplying anti-corrosion 3LPE coating
line . We provide 3LPE integrated external coating equipment, which
can be used in underground or underwater environment. Our company
also produces 3LPP, FBE, internal epoxy and other anticorrosive
pipeline coating machines.
Standards for the manufacture of 3LPE pipes include: