Protecting Subsea Oilfield Flow Bases with the Cocoon Subsea System

UK-based Composite Solutions, a Pipex px® company, designs and manufactures Cocoon and Shroud™ subsea protection systems that protect objects dropped during drilling or subsea oilfield flowbases from the marine environment, and even prevent fishing trawler net incidences. The Cocoon and Shroud™ subsea protection systems use Strongwell components such as DURADEK® I-6000 1-1/2" (38 mm) grating, 8" (203 mm) EXTREN DWB® (all glass), and EXTREN® series 625 profiles and plate.

Pipex px® Introduces the Cocoon Subsea System

The Cocoon employs a special skeletal “clam” design with an external surface using lightweight fiberglass reinforced polymer (FRP) materials. This ensures safe deflection or easy retrieval of the fishing gear. Located at the base of the Cocoon, the Shroud element enables simple offshore deployment and installation to well heads. The first Cocoon was first installed a decade ago and today there are more than 23 in the North Sea.

Strongwell materials are light weight, resistant to corrosion and can withstand impact which made it easy to choose them. Vinyl ester products from Strongwell were selected for improved performance in harsh subsea conditions (100 m/650 ft. depth+).

Pipex px® Introduces the Cocoon Subsea System

Case Study: EXTREN®

EXTREN® Riding High in Downtown Waikiki

Hawaiian fabricator, Plas-Tech Ltd. used Strongwell’s products for an architectural trellis overlooking Waikiki, Honolulu, Hawaii. The trellis sits on top of the Waikiki Shopping Plaza situated at the heart of the city on the popular Kalakaua Avenue. The retail center has more than 50 tenants including national brands LeSportSac and GUESS® as well as several local favorites such as Ukulele House, Local Motion® and Higgins Harte International Galleries™.

For the trellis design, MGA Architecture specified the use of Strongwell’s EXTREN® 2" x 6-1/2" rectangular tubes. Plas-Tech constructed the trellis components by molding, assembling and painting the outrigger beams. MGA’s unique design was based on the native Hawaiian culture to evoke emotional experience and sensory response while merging in with the overly urban character of contemporary Waikiki. The project went smoothly and both Plas-Tech and MGA are pleased with the fabricated architectural trellis.

EXTREN® Riding High in Downtown Waikiki

Strongwell’s FRP structural shapes have impressed MGA Architecture so much that it intends to add five more trellis systems on the neighboring building. Strongwell components will also be used by MGA Architecture for another future project.

Case Study: SAFRAIL™ and DURADEK®

FRP Well-Suited for Corrosive Wastewater Treatment Environments

Back in 2008, a handrail and grating system was deployed and installed at the Saginaw, Michigan wastewater treatment plant. Corrosion resistance around the sludge basin was the key requirement of the plant and the installation was done to address this issue. Strongwell’s yellow SAFRAIL™ handrail systems, EXTREN® and DURADEK® I-6000 structural shapes were included in the installation. All Strongwell’s products are strong, impact resistant, and particularly well suited for corrosive environments.

FRP Well-Suited for Corrosive Wastewater Treatment Environments

The Installers from Gerace Corporation and the Fabricator Joe Cavanaugh of Titus Welding were impressed both with the products and the ease of fabricating and installing the project.


Easy Access with Fabricated Covers

Located in Fort Collins, Colorado, the Mulberry wastewater treatment plant installed Strongwell’s fabricated FRP covers. The treatment plant needed a removable cover that spans an 8 foot area without building extra structure. Pipe Valve & Fitting, a Strongwell distributor, provided COMPOSOLITE® covers instead of aluminum covers to Montgomery, Watson and Harza Engineering and their Contractor, Hydro Construction.

Easy Access with Fabricated Covers

The COMPOSOLITE® covers were installed in an 8' x 40' section and several 8' x 8' sections. A standard cover such as aluminum was not selected because it is not strong enough. Usually, aluminum covers are not designed for foot traffic. The COMPOSOLITE® covers feature a hollow core construction that made it easy to accept a stainless steel recessed T-Bar handle for a smooth, even surface. The project was carried out in phases in 2010 and 2011.

Case Study: EXTREN® and SAFRAIL™

Fiberglass Fencing: Still Strong Eleven Years Later

In 2000, a Drury Inn Hotel situated in Englewood, Colorado, created a new look for its exterior and fencing railings that saved considerable costs on replacement and maintenance. Eleven years later, the fencing is just as strong and attractive. Due to ease of assembly, low maintenance and lower installed costs of fiberglass, the hotel chain chose this material. The fiberglass fencing was fabricated from 2" and 1-3/4" EXTREN® square tubing, custom pultruded in black, and finally designed to resemble wrought iron. FRP fencing is resistant to corrosion and hence provides a long-lasting alternative to steel or iron. At the Drury Inn, steel handrail has to be frequently painted, but the FRP fence or the FRP perimeter fence installed around the pool area no longer have to be repainted.

Fiberglass Fencing: Still Strong Eleven Years Later

The latest FRP fabricated railings and fencings are now standard for all new construction and renovations at the Drury Inn. FRP fabricated railings and fencings are used for exterior railings and perimeter fencing for pools, stairs and balconies. The FRP fencing has been shown to be maintenance-free and long-lasting— both significant for Drury Inns which has over 200 properties across the Midwest.

Product Alert

New SAFRAIL™ Option: Channel Top

Strongwell has now added the latest SAFRAIL™ channel top option to the industrial fiberglass handrail line. It is a low-cost commercial railing system specifically designed for long runs on walkways and platforms. Designed for fabrication efficiency, the railing system is not especially suitable for stair rails with twists and turns. The SAFRAIL™ channel top can be used together with square and round SAFRAIL™, as required.

New SAFRAIL™ Option: Channel Top

A polyester, fire-retardant resin is used to pultrude the standard SAFRAIL™ channel top handrail system. The handrail system comes with a UV inhibitor for extra resistance to ultraviolet corrosion and degradation. Yellow is the standard color, but other colors are also available upon request.

New SAFRAIL™ Option: Channel Top

GRIDFORM™ Design Guide Update

GRIDFORM™ Design Guide Update

The GRIDFORM™ Design Guide has been introduced to help Structural Engineers determine whether GRIDFORM™ can be used as the internal reinforcement system for reinforced concrete bridge decks, instead of steel rebar. GRIDFORM™ is a prefabricated FRP double-layer grating, concrete-reinforcing system with integral stay-in-place (SIP) form for vehicular bridge decks.

Since FRP offers a corrosion-free reinforcement system for the concrete, the expected lifespan of a GRIDFORM™ bridge deck is several times that of steel reinforced concrete bridge decks. In order to account for deflection caused by Uniform Loads, the GRIDFORM™ Design Guide program has been updated. In addition, testing of the main bars (GV-2) has increased the size of the sample to 30.


This information has been sourced, reviewed and adapted from materials provided by Strongwell Corporation.

For more information on this source, please visit Strongwell Corporation.


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