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FRP / Engineered Composite Gates vs. Traditional Metal Gates

TPlasti-Fab, Inc.he overall benefits of a Fiberglass Reinforced Plastic (FRP) product compared to aluminum, coated aluminum and steel products, go far beyond what is immediately evident when reviewing technical data sheets and test results.  Depending on the environment and severity of product exposure, the practical requirements and suggestions for use along with comparative data collected from multiple market segments – a very clear picture can be constructed for the products performance over a short and extended time period.

Wastewater Flow Control Products are a perfect example.  Sluice gates, slide gates, stop gates, stop logs and weirs are integral to the process and can be designed and manufactured utilizing various metals and can also be manufactured in Fiberglass Reinforced Plastic (FRP) – an Engineered Composite.

There are numerous areas of consideration in the decision making process for selecting flow control products.  With quality, performance and an extended life cycle at the top of the list, nothing can match the benefits of a FRP/Engineered Composites product for use in the water and wastewater market segment, particularly in corrosive wastewater environments where microbial activity can directly oxidize metals or generate corrosive hydrogen sulfide.

An FRP/Engineered Composite product – is consistent from its surface, throughout the thickness and extending to the back side of the piece.  The thermoset reaction of the chemistry – creates a homogeneous consistency throughout the matrix of the item.  If an FRP/Engineered Composite product is exposed to adverse conditions for extended periods of time or ever abraded or gouged – there is no loss in the physical properties or chemical resistance.

Aluminum Slide Gate
Aluminum Slide Gate Corroded Below Waterline

This is not the case with metal products.   First, and perhaps most important, a coating on metal, regardless if it is paint on a car, Teflon on a cooking skillet or if a flow control gate has been anodized – it is strictly a surface coating and typically a very thin mil thickness.  It is not integral to the entire product and when worn away, abraded or deteriorated by exposure – will leave the bare metal exposed.

This is extremely important at areas of friction – such as the guide rails and channels – where metal gates are inserted – and will commonly be the first and most immediate area where abrasion and the ill effects of exposure will occur.  Perhaps this is why most metal gates come with a recommendation to “exercise the gate” on a periodic basis?

Deterioration, abrasion and oxidation that will occur at this critical area can quickly negate the gates primary function – to freely open and close when needed.

Cast Iron Sluice Gate
Cast Iron Sluice Gate “Frozen” In Place

FRP/Engineered Composite gates – will not have this problem.  After months and even years in a static condition – when it is necessary to engage the gates, they will move freely when opened and closed.

The longevity and life cycle of a FRP/Engineered Composite product can be detailed in a number of ways.

One interesting perspective comes from a focus on recycling.

For a number of years – in Europe, household recycling has not been a volunteer activity – it is mandatory.  Paper, glass, cans – must be separated and disposed of in a prescribed fashion.  After establishing a protocol with small items – their focus turned to larger products.

What do you do with an automobile that is 12 or 15 years old and has reached the end of its life cycle?

You have a large mass of aluminum and steel that is commonly pitted, damaged and rusted – in some cases, it may be more structurally sound because of Bondo than metal.

What do you do with it?

Recycle – the car can go to the grinder and be reduced to small shards of metal that can be melted down and reused to manufacture new products.

When the attention turned to boats – things changed a little.

A wooden boat is easy to address – it is biodegradable.  A metal boat – much like an automobile – can be reduced to scrap and be recycled.

But- what do you do with an FRP/Engineered Composites boat?

A 20 or 25 year old FRP/Engineered Composites boat – may have carpet and seating that is deteriorated, an engine that is beyond economic repair and aluminum mooring cleats and side rails that are rusted – but – the structural FRP/Engineered Composite hull of the boat is as sound as the day it was manufactured.  If you could extract a hull sample section of this water craft that is ready for retirement and compare it to a similar sample from the day it was manufactured – there would be little if any change in the physical properties.  If you were to come back in another 10 years – the pigmented resin or gel-coat used for aesthetics might be a little more faded from UV and perhaps a little more stained below the water line – but again, the structural integrity would remain excellent.

Sluice Gate
Plasti-Fab FRP Heavy Duty Titeseal Gates

While most all the materials used in FRP/Engineered Composites production can offer the unique benefits detailed above –how they are processed – the laminate schedule, the volume fraction (glass-to-resin ratio) and method of production – make a major difference in the overall performance characteristics of each individual product and therefore each individual FRP/Engineered Composite manufacturer.

Plasti-Fab, Inc. utilizes the most advanced technology and fabrication processes to manufacturer our wastewater flow control products for the water and wastewater industry.  Closed mold RTM (resin transfer molding) and vacuum infusion are sophisticated methods of manufacturing that enable us to build the highest quality and consistent products available.  In most FRP production applications – manufacturers might achieve a 30% to 32% ratio (fiberglass content as related to the resin).  The technology utilized and refined by Plasti-Fab, Inc. allows us to fabricate FRP/Engineered Composite parts with a higher percentage of fiberglass content.

The results are a stronger and lighter part that is more consistent and uniform and which will meet and maintain required tolerances and dimensions better than any product available which is why we offer a 25 year warranty covering failure from corrosion on all composite components of our products.  Plasti-Fab, Inc. manufactures slide gates, sluice gates, flap gates, stop gates, stop logs, and weir gates for virtually any application and size.

Plasti-Fab, Inc. Gate Brochure

Courtesy of Mike Keegan of Plasti-Fab, Inc.


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