Author: AKeson

Industrial Corrosion applications

A lot of FRP materials are used in the chemical and industrial sectors of the economy. The non-corrosive and non-conductive properties of the fiberglass materials have many advantages over steel and other materials. Large tanks, pipes, and structures are fabricated both off-site and on-site of the final installation. The best quality comes from the controlled environment of the factory. However, the physical size may necessitate that structures are built in pieces for transport and installation. They onsite workers can join the pieces to become one. There are several joining methods, including adhesive, mechanical, and chemical bonding (fiberglass tabbing). There are specialized resins used for these corrosion New events, new promotions and new bonus opportunities are constantly entering the Platinum Play fold. applications. These resins are the best at resisting chemical interaction, and are made to have high impact strengths to resist failure of the overall structure. Fiberglass resin and glass is normally non conductive, both with heat and electricity. This can be adventageous for negating concerns for electrocution. The flipside is that static electricity can build up and discharge randomly in a search for a grounding path. Heat conduction is poor so it can act as an insulator and heat sink. Many of the pipes and tanks are manufactured using a process called filament winding. This is a process where a round mandrel acts as a mold and rotates...

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Bagging/Infusion On The Cheap

Vacuum Infusion and Vacuum Bagging can be accomplished are not only reserved for industry and can be accomplished in a workshop setting. Relatively inexpensively as well. One of the major variables is the shape of the part trying to be built. We will look at a flatstock for now. The desired outcome could be either a test panel or a piece needed for flat construction. The mold will be the difference between this and any other more complicated shape. The mold must be able to be sealed from the atmosphere and waxed for release of the finished part, so my favorite “mold” is either a flat sheet of steel or a sheet of plate glass depending upon desired surface finish. This must then be waxed up with some paste wax to enable part release. I always like to start with creating the perimeter seal. The 1/8 or 3/16 inch thick by 1/2″ wide gray butyl tape is the best. This is basically sticky on both sides and has wax paper on one side. It is sold at infusion suppliers or online as well. My little secret is that it is also sold at building supply stores, as it is used on polebuilding construction projects when sheets of steel siding/roofing are sealed together with this stuff. So this is unrolled and pushed down onto the mold and the wax paper...

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Vacuum Infusion Processing

Resin infusion processing offers several advantages over traditional open mold processing techniques. All of the reinforcements and core materials are placed in the mold without resin, so care can be taken for close fit and proper orientation. And it is a lot cleaner without the sticky resin. Resin waste is typically lower because all of the resin is added at once. VOC”s are reduced as well, and are only emitted from the open mixing containers. There is much less worker interface with messy and stick resin on people and tools so cleanup materials and personal protection equipment expenses are reduced. The laminate itself is typically more consolidated, uniform, and visually pleasing. One of the considerations that needs to be taken into account is that the ratios are different and the glass and resin are more compacted by the process. Using the same layup schedule would result in a thinner laminate that is lighter weight and uses less resin. One drawback to this is that the cross sectional area is less, usually resulting in a loss of stiffness. This can be regained by increasing the core thickness to compensate for that loss and to restore overall panel thickness. Infusion processing does require specialized equipment, consumables, and materials. The resins need to have much lower viscosity(flow like water). The core and glass need to have holes and channels for the resin...

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A couple of design considerations

FRP Composites have their own special set of considerations in design and use. And we will discuss a few here. The traditional fiberglass (unsaturated polyester with glass reinforcement) uses gelcoat on the molded (decorated) side. This is really only one side of the part, as this is not a matched-mold process. So the back side needs to be hidden from view or covered with another material, etc. A boat, for example has a Deck and a Hull that are mated together so that the back sides of the parts are hidden from view. The inside of the cabin is then upholstered and trimmed out for comfort and decoration. I have worked with fiberglass tabletops before where the top side is gelcoated in a decorative finish and the edge wraps down and trimmed. All of the unsightly surfaces face the floor where they cannot be viewed. There are a few closed-mold processes that can be implemented, but these really only achieve a Class B surface out of the mold. With rework and repair, a Class A surface can be accomplished. I know of some folks that make Boat Access Hatches where they repair the backside (bottom) and rework it so it looks pleasant when opened. Molded-in features must be used with caution. Sharp edges must be avoided because the process hates having to get resin and reinforcement into them, and...

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Curing Mechanisms

Temperature plays an important role in the curing process of the resins used in composites. Many of the resins are setup for room-temperature curing. This requires that the ambient room temperature is ideally set between 65 and 75 degrees. And that the resin itself is near this temperature. academic thesis The old rule of thumb is that a drum of resin takes about 24 hours to get to room temp when moved in from shipping or storage. lowest price on levitra These room temperature cured resins have windows of open working time before the curing cycle begins to happen. Elevated temperatures in the summer can cause havoc, but can be managed with special mixtures and ingredients. Some resins cure with time and elevated temperatures, which are achieved with the use of ovens. These allow for nearly unlimited open working time before cure. When things are satisfactorily placed, the temperatures are elevated to start the cure process. UV Light is another curing mechanism that has special applications and takes the temperature consideration away. This has a big use with the infrastructure restoration industries working onsite and underground. It is much more of a specialized niche...

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