Envirawrap In preparing our latest technology package, we have based our design around a combination |
Description
Envirawrap is a wraparound corrosion protection jacket system specifically designed to be an easily installed, retrofit one-piece sleeve to eliminate corrosion on pipework, jetty piles in the splash zone, offshore platform structures and subsea pipelines.
Envirawrap’s elastomeric properties and flanged closure system provide the unique facility of removal and subsequent re-installation to facilitate routine inspection of the substrate throughout the service life, without need to buy more materials for re-installation of the jackets. Hoop tension imposed in the tough, resilient outer skin acts to force the inner layer against the surface of the substrate, thereby causing the sealant and its corrosion inhibitor to form a close association with the substrate. The thixotropic nature of the sealant forces it into any surface irregularities thereby providing a seal, terminating the supply of oxygenated water to the pipe, riser or pile surface. The system is modular and therefore a multiplicity of units may be deployed to encapsulate virtually any length of pipework.
Design
In preparing our latest technology package, we have based our design around a combination of materials with proven performance within a variety of operational environments. The components which combine to form the Envirawrap system are resistant to long term immersion in both sea water and fresh water, and to the attendant biological and chemical attack. In addition, the system will withstand attack from environmental UV, ozone and temperature variations while providing permanent protection in service by resisting wave action in the splash zone, seabed erosion, and may be installed in high tidal currents.
The materials in the system are stressed below their operational limits ensuring a high safety factor in all parameters while in service. The basic objective was to design a system that, while fulfilling all of the requirements once in service, should be as quick and easy to install as possible. No labour intensive ancillary materials such as tapes, sealants or adhesives are used in order to reduce to a minimum the possibility of human error and/or non-compatibility of components in the installation of the system.
Construction
Envirawrap panels are a multi-layer, monocoque construction, consisting of a polymeric textile, memory enhanced, reinforcing element, encapsulated within the polyurethane matrix and the outer layer and in-line bonded to a polyester or polypropylene, penetration resistant felt. This inner felt layer is factory impregnated with a corrosion inhibitor, contained within a water resistant thixotropic gel. In designing the system, we considered the following operational parameters in addition to those necessary for the material to retain hoop tension throughout the projected operational life of the fabric:
- Toughness
- Abrasion resistance
- Good UV resistance
- Good ozone resistance
- Resistance to high climatic temperature
- Good adhesion to fabrics
- Proven long life under sea water
- Resistance to hydrocarbon oil contamination
- Is not degraded by any form of marine life
- Oxidization resistance
- Permits pipe/structure movement
- Excellent flexibility
Special Characteristics
Primary Penetration Layer
Polyester geotextile felt, which provides the primary penetration and carrier for the corrosion inhibiting gel, is in-line bonded during the production of the multi-layer fabric to become an integral part of the Envirawrap fabric and enhancing penetration resistance.
The thixotropic gel and its attendant “active” corrosion inhibitors are factory applied to the point of saturation in quantities calculated to provide protection throughout the operational life of the product.
Thixotropic Inhibited Sealant Gel
Petrolatum based gel exhibiting a high degree of thixotropy, liquefying at installation to convey the active corrosion inhibiting additives to the interstices of the substrate, whilst solidifying once again soon after.
The gel is intensely hydrophobic, dispersing water on contact with the substrate, while remaining inert to the physical and chemical effect of marine and fresh water throughout the operational lifetime of the system.
Applied at elevated temperature in liquid form to the geotextile felt to the point of saturation. (≈3 – 4kg/m2). Once applied, the gel exhibits stability through an extensive operational temperature range with slump and melt points being outside those encountered in most applications.
Flanged Closure Seal
Envirawrap units are tensioned and closed via marine and impact resistant PVC bolted flanges designed so that the fabric and supplementary felt seal under compression and provide the environmental closure seal.
Stainless steel 316L fasteners are provided as a standard, however, Monel, Titanium, or Inconel alloy fasteners are available upon request.
Literature provided
Project specific Installation Procedures will be created for each particular case, as location and conditions will vary.
Data sheets will also be tailor made for specific projects.
Network Uses
Envirawrap is an ideal solution to corrosion problems encountered with most bridge crossings – canals, rail, river crossings.
Prices & Ordering
Envirawrap will be quoted for on a case by case basis.
Approvals / Recognised Standards
At present Envirawrap does not have any formal approvals but is specified by many of the majors in the oil industry eg Exxon, BP, SHELL, Total, Conoco, Texaco, Saudi Aramco, and other industrial giants eg DOW chemical, Port Authority of New York and New Jersey.
Warranty & Technical Support
Ongoing technical support is available from our head office, with the product having a 10-year warranty. At present this product will only be available as supply & fit. If demands for the product are high, it may be possible to create a training program to enable the Envirawrap to be a supply only product as well as supply & fit.
Training Arrangement
Please see ‘Literature Provided’ above.
Maintenance Requirements
To facilitate complete post installation inspection and/or maintenance of the substrate at intervals indicated by the client, the ability exists to remove and refit Envirawrap units without detriment to the long term performance of the material.
Description of any special technique or unique tools, plant & equipment required
Please see ‘Literature Provided’ above.
Future Use – Purchasing, Delivery, Packaging & Recycling arrangements
Envirawrap costs will be quoted on a case by case basis.