The Internal Structure of the FRP Storage Tank and Repair Method

 

 

Not many people know the internal structure of FRP storage tanks. FRP tank wall is divided into an internal layer, secondary internal layer, and external surface. Next, we introduce these internal structures.

 

FRP storage tank internal structure

1. FRP tank lining layer

FRP storage tank lining layer consists of the inner surface layer and secondary inner layer, the matrix should be used bisphenol A type unsaturated polyester resin, vinyl ester resin, and other resins with excellent corrosion resistance. Reinforcing materials are glass fiber surface felt, glass fiber short-cut raw silk felt and glass fiber untwisted roving cloth, etc.

2. FRP storage tank secondary inner layer

It is made of general-purpose unsaturated polyester resin as the matrix and glass fiber twist-free roving as the reinforcing material. Resin content is 45%-50%, the thickness of the layer is determined by the design calculation.

3. FRP storage tank outer surface layer

The unsaturated polyester resin with excellent weather resistance is used as the matrix, and the glass fiber surface mat or glass fiber untwisted roving cloth (thickness less than 0.16mm) is used as the reinforcing material, with resin content more than 55%, and the thickness of the layer is 0.2-0.5mm.

 

Repair of FRP storage tank

Although the FRP performance is superior, in terms of hardness, corrosion prevention is good, but also for one reason or another, resulting in FRP storage tank leakage, and FRP damage, in most cases to replace the main, repair is very difficult, usually with the gluing method or hot welding method to restore it, here is a brief introduction to the gluing method of repair.

(1) cleaning FRP storage tank. First of all, the damaged tank will be disassembled first, clean and dry it, and do the prerequisite work of repair.

(2) according to the size of the broken part cut appropriate large glass fiber cloth, after baking wax removal, heating until not smoking, take care not to fold.

(3) Glue preparation. There are many kinds of glue formulations, but in general, the epoxy resin and polyamide resin two kinds of resin in the ratio of 1:1 into a wide mouth container, stirring with a stick, the viscosity is generally good to lift the stick does not pull the wire, pay attention to the principle of rather less than more, not too much at a time, to just enough to use up as good, followed by uneven mixing, with a good glue after a period of time will be Self-curing, resulting in waste.

(4) Apply glue. First, use a stiff brush to brush a layer of glue in the inner surface of the glass fiber reinforced plastic tank, and then the prepared glass cloth on the surface of the glue, gently pat the pressure to make it fit tightly so that the glue penetrate the glass cloth; the first layer of good penetration and then coated with a second layer of glue, paste the second layer of glass cloth. So the cycle coated a few layers on it, take care not to get too thick in the coating and framing.

(5) Curing. After painting a higher temperature place to let its natural curing, although it takes a longer time, but definitely not with open fire baking. Wait for its natural curing, and then polish the edges, openings, after spraying, the repair is complete, the glass fiber reinforced plastic tank and restore the strong and durable.

 

We are an FRP storage tank supplier, please feel free to contact us if you need them!

Can FRP pipes be customized?

FRP (glass fiber reinforced plastic) has good designability, shape performance and easy maintenance. Compared with steel, FRP (glass fiber reinforced plastic) has very high corrosion resistance, the specific gravity of 1.5 to 1.9, much lower than steel's 7.8, but its mechanical strength is higher than steel, FRP containers have the advantages of a low coefficient of thermal expansion and good insulation performance, and have been widely used in many fields Applications.

 

According to the shape of the medium, FRP containers can be divided into three categories: liquid, gas and solid tanks; according to the pressure level, they can be divided into two categories: ATM tanks and pressure tanks; according to the shape of containers, they can be divided into three categories: horizontal cylindrical tanks, vertical cylindrical tanks and rectangular tanks; and PVC/FRP, PP/FRP and PVDF/FRP composite tanks.

 

Hebei Yongchang Composite Technology Co., Ltd. is a professional FRP container manufacturer in China. With exquisite technology, reliable quality and good reputation, Hebei Yongchang FRP containers are widely used in chemical fertilizer and pesticide, electronic and electric power, pharmaceutical, petrochemical, water treatment, citric acid and food fermentation, and can be manufactured with a maximum diameter of 25000mm, volume is 5000m.

 

Special attention needs to be paid here.

When ordering FRP pipe, the following data needs to be provided to us.

Pipe diameter

Design and working temperature of the working fluid.

Design, operating, surge, vacuum, and test pressures.

Live load of the buried pipe.

Maximum/minimum burial depth and trench width.

Detailed information on soil properties and trench preparation.

 

Yongchang FRP pipe performance and characteristics

1. Corrosion resistance: Different types of anti-corrosion lining resins are selected for different acid, alkali and salt environments, as well as various oils, seawater and organic solvents.

2. Lightweight, easy to maintain and durable.

3. Easy to install: There is no technical limitation on the length of the FRP pipeline, but considering transportation, the length of the pipeline is generally less than 12m, so the number of joints is greatly reduced. Due to the lightweight of FRP, the pipeline can also be installed manually or by light installation equipment, which is convenient and fast.

4. Good applicability: the existing FRP pipeline standard diameter is between 25mm-4000mm, the long-term pressure-bearing capacity is generally less than 1.6Mpa, and according to the special needs of users, it can reach a higher pressure of 6.4Mpa.

5. High conveying capacity: smooth pipe wall N-S 0.0084. It has a higher flow rate compared with a traditional pipeline of the same diameter, so it can save pump energy and prolong project life.

6. Low permeability: Due to the good sealing connection and the longer length of each pipe, FRP pipes have lower permeability than traditional pipes, thus greatly reducing the risk of groundwater infiltration into the pipes and media penetration as well as pollution of the environment.

7. Strict testing standards: Our company has advanced testing equipment and strictly enforces inspection standards to ensure product quality. Relevant standards: ASTM, AWWA, ASME, etc.

8. Low cost and long life: Hebei Yongchang FRP products have a long service life, basically no maintenance, and very low installation and transportation cost.

 

FRP pipe connection requirements

Interface operation, the ambient temperature is not less than 10 ℃; curing temperature after bonding is not less than 15 ℃, curing insulation time is not less than 12 hours. Paste the interface according to the layer design. According to the sample data, planned gel time, ambient temperature, etc., mix the resin and stir it thoroughly. When the bonding thickness is more than 10mm, it should be formed in stages. Before each molding, the curing surface of the last molding should be sanded.

 

Our Yongchang FRP / FRP pipes are designed and manufactured according to customer requirements in various sizes and configurations. We can manufacture pipes of any size and pressure and can make composite pipes such as PVC/FRP, PP/FRP, PVDF/FRP, etc. according to the conditions of use. Our designers can calculate the circumferential stress, axial stress and bending Poisson's ratio coefficients of products based on your available space, chemical fluid requirements and applicable natural conditions, and then give product selection, product thickness and layering. We have detailed manufacturing process parameters. All of our pipe designs meet industry standards such as ASTM D2996 Standard Specification for Fiber Wound "Glass Fiber" (Glass Fiber Reinforced Thermoset Resin) Pipe for Fiber Wound Pipe.

 

Common codes and standards that govern the details of FRP pipe are

ISO 7370

ANSI/AWWA C950

AWWA M45

ISO 14692

AWWA C590

ISO 10467

BS 5480

ISO 10639

ASTM d2996, ASTM d2997, Astm d5421, Astm d4024, Astm d5685

 

Yongchang offers long-term corrosion solutions and the absolute longest product life for standard fiberglass tubes, custom tubes, special manifold systems, pipes, or chimneys. Contact us and you can get advice from our professionals depending on the use scenario!

Guide to installing FRP pipes

Although installation is not usually considered part of the design of a piping system, it is an important part of a successful system and we feel it needs to be emphasized here. There is no doubt that more problems occur in FRP piping systems due to improper installation than any other single cause, and there are many steps that must be followed to ensure that problems do not occur in the future.

 

① FRP pipe should be inspected for appearance and size before construction, and accepted according to the factory certificate of conformity.

② Pipeline installation drawings are the basis for pipeline installation works, the laying of FRP/PVC pipe (including the form of connection, coordinates, elevation, slope, slope direction, etc.) support, FRP/PVC pipe and equipment, pipeline accessories connection, pipeline accessories installation location, support, etc., should be in line with the design drawings, such as changes, must be resolved in consultation with the design unit.

③ Pipe installation, according to the pipe section divided by the pipe installation diagram, can be installed from one end of the pipe in order to the other end of the pipe accessories, and then set up brackets or supports (if necessary, temporary support is required during the installation process). When the pipe is lifted, the outer wall surface must take protective measures, and direct contact with the wire rope is prohibited, so as not to cause local stress.

④ The connection point of FRP pipe is only allowed in the straight pipe part. The distance between the butt welding connection point and the edge of the pipe support should be greater than the outer diameter of the pipe and not less than 100mm; the distance between the socket connection and the edge of the pipe support should be greater than 150mm.

⑤ The connection structure of the pipe is in the form of socket connection, flange connection (welded ring flange connection and composite flat welding flange connection), and butt welding connection. This project will determine the installation method according to the specific requirements of the design documents.

(6) The installation workers engaged in welding must hold a welder's certificate and be familiar with the performance of FRP/PVC pipe adhesive and its installation method, and have skilled PVC welding operation ability.

(7) Before the pipe is connected by socket, the inner wall dirt of the PVC pipe should be removed from the connection, and then the socket should be inserted into the socket, and the socket should not be skewed, cracked or other defects, and the socket depth should be reached before PVC welding is carried out.

⑧ The socket part should be enhanced by FRP, evenly coated with a layer of R glue at the enhancement, coating thickness is uniform, shall not leak and flow, then wrap a layer of glass cloth, coated with unsaturated resin, wrap glass cloth, repeatedly until the thickness reaches the requirements.

⑨ When the socket installation fails to pass the need for rework, the socket plug and socket must be re-made, and shall not use the used socket plug.

⑩ When flange is connected to the pipe, both inside and outside sides must be welded to the pipe, the flange surface and pipe axis inclination should be less than or equal to 1/100 of the outside diameter of the pipe. flange connection should be strictly aligned, the maximum allowable deviation in the axial direction is not more than 2mm, and the method of strong tightening bolts should not be used to eliminate skew. Tighten the bolts in two times, the first time evenly and symmetrically screwed once, and then tighten the bolts again.

 

FRP pipe connection requirements

When the interface works, the ambient temperature is not less than 10℃; the curing temperature after bonding is not less than 15℃, and the curing holding time is not less than 12 hours. Design the paste interface according to the laminate. According to the sample data, planned gel time, ambient temperature, etc., mix the resin and stir thoroughly. When the bonding thickness is more than 10mm, it should be formed in stages. Before each molding, the cured surface of the last molding should be polished.

 

Yongchang specializes in the production of various, FRP chemical storage tanks and FRP process tube can be customized! Ex-factory price, perfect after-sales service.

 

Application of FRP pipe

Glass fiber reinforced pipes are widely used in various industries for their excellent product performance. And it has played an important role in various industries.

 

A. Petroleum, chemical, pharmaceutical, biogas industry: such as chlor-alkali, potassium sulfate fertilizer, paper, acid regeneration system.

 

B. Water treatment industry including desalination, industrial wastewater treatment output and input, pure water system.

 

C. Liquid transportation industry: urban water supply, urban drainage, irrigation systems.

 

D. Power industry: flue gas flue, desulfurization system, circulating water, cable pipe, glass fiber reinforced plastic chimney.

 

E. Environmental protection: sewage odor recovery, workshop waste gas treatment, factory air purification, biogas desulfurization and purification.

 

F. Other applications: Manufacturing process vessels

 

Industry Standard: ASME RTP-1-2007 Reinforced Thermoset Plastic Corrosion-Resistant Equipment is an American Society of Mechanical Engineers standard for the fabrication of vessels for use in corrosive and noncorrosive applications at pressures up to 15 psig. Manufacturers must be ASME RTP-1 certified.

 

Above and Below Ground* FRP Potable Water Tanks

 

Applications: National and state parks, schools, campgrounds, cisterns, resorts

 

Industry Standards: Materials meet NSF Standard 61 - Drinking Water System Components - Health Effects and * UL 1316

 

Above and Below Ground* Non-potable FRP Fireproof Water Tanks

 

Application: Standby fire protection water storage.

 

INDUSTRY STANDARDS: Conforms to NFPA 22: Private Fire Protection Water Tanks (2014), AWWA D120 Aboveground Thermoset Fiberglass Reinforced Water Tanks and AWWA D121 Bolted Aboveground Thermoset Fiberglass Reinforced Plastic Panel Tanks and *UL 1316.

 

Above and below ground* oil/water separators

 

Applications: 1,000 to 30,000 gallon separator systems.

 

Industry Standards: Compliant with UL Subject 2215, U.S. Coast Guard Test Method 46 CFR 162.050, API Bulletin Numbers 421 and 1630. EPA Test Methods 413.1 and 413.2 and *UL 1316.

 

Underground* FRP Chemical Storage Tanks

 

Applications: Agricultural chemicals, road treatment chemicals, irrigation system collection, water treatment chemicals, leachate, refinery runoff, airport de-icing (glycol), medical emergency drainage collection, firefighting foam storage, paint manufacturing, acid wash solutions, fish hatchery water, pharmaceutical manufacturing catch basins, leather processing chemicals.

 

Industry Standards: UL 1316 compliant, materials include a matrix of high quality resins, fiberglass and fillers, compatible with the above chemical materials.

 

Underground residential FRP tanks for septic systems

 

Applications: 1,000 and 1,500 gallon septic systems.

 

Industry Standards: Meets International Association of Plumbing and Mechanical Officials IAPMO PSI-2000A standards

 

The main reasons for the increased use and popularity of fiberglass are key benefits such as high strength-to-weight ratio, dimensional stability, good mechanical properties, ease of installation, reduced installation costs, lower maintenance costs, and overall durability under extreme conditions. Likewise, another advantage of fiberglass tubing over traditional construction materials is its smoother inner surface. This characteristic, with its smooth inner bore, resists scale deposits and can produce greater service fluid flow throughout the life of the project.

 

What is FRP pipe?

The complete form of FRP is glass fiber reinforced plastic, which is a composite material consisting of a fiber-reinforced polymer matrix. Thus, FRP pipe is a pipe manufactured from FRP material by contact molding or fiber winding methods. Various types of resins, such as thermosetting polyesters, epoxy resins, phenolic resins, etc., are used to obtain specific FRP pipe properties in the final product. The most widely used reinforcement material is glass fiber "E-glass". FRP piping systems are used worldwide as a corrosion resistant alternative to metal piping. FRP piping systems are available in a variety of sizes, ranging from 1" to 144".

 

FRP pipe is manufactured by a winding process that reinforces thermosetting epoxy resins with continuous glass filaments. As the resins cure, they undergo an irreversible chemical reaction, giving them excellent resistance to temperature changes, while the glass fibers give them excellent mechanical strength. In microtunnels, steel casing is used for jacking where significant force is required. frp pipe is now widely used for this purpose because of the reduced force of hydraulic jacks, making it cost effective and also allowing longer lengths to be installed. frp can also be used for non-excavation repair methods such as slip lining. frp is resistant to corrosion and chemicals, making it an ideal material for pipes carrying such wastewater.

 

Classification of FRP pipes

According to the shape of media, FRP vessels can be divided into three categories of liquid, gas, solid tank; according to the pressure grade,can be divided into two categories of ATM tank and pressure tank; According to shape of vessel, can be divided into three categories of horizontal cylinder tank, vertical cylinder tank, rectangle tank; And PVC/FRP, PP/FRP, PVDF/FRP composite tanks.

 

Applications of FRP pipes

The use of FRP piping is increasing due to its high durability, corrosion resistance and moderate strength.FRP piping systems are used in various industries, such as

Drinking water and seawater desalination industries

Chemical, petrochemical, oil and gas industries.

Piping and ventilation ducts

Irrigation and sanitation services

Water distribution and delivery

Slurry piping

Power plants, etc.

 

Hebei Yongchang Composite Material Technology Co., Ltd is professional FRP vessel manufacturer in China, depend on the sophisticated technique, creditable quality, good prestige,It can be designed and manufactured according to customer requirements, with various sizes and configurations. We can manufacture pipes of any specification and pressure, and can make PVC / FRP, PP / FRP, PVDF / FRP and other composite pipes according to the service conditions. Our designers can calculate the circumferential stress, axial stress and bending Poisson's ratio coefficient of the product according to your available space, chemical fluid requirements and applicable natural conditions, and then give the product selection, product thickness and delamination. Contact us, you can get our professional advice according to the use scenario!

How FRP Pipe is Constructed?

 

 

Three different processes are commonly used to fabricate fiber reinforced plastic pipe: centrifugal casting, filament winding, and hand lay-up. Filament winding and centrifugal casting are used to make pipe up to approximately 12 inches in diameter, with filament winding being the most common. Hand lay-up is generally used for larger diameter pipes, and for asymmetric shapes.

 

Centrifugal Casting

The centrifugal casting process involves layering glass cloth on the inside walls of a tubular mold which is rotated at high speed. Catalyzed liquid resin is then injected into the rotating mold. Centrifugal force ensures that the reinforcing fibers are thoroughly saturated with resin and serves to drive out air bubbles that might compromise the physical properties of the pipe. The mold continues to rotate while the resin cures.

 

Filament Winding

In filament winding, continuous fiberglass filaments, called rovings, are saturated with catalyzed liquid resin and helically wound around polished steel mandrels. Typically, the fibers are fed through a mechanical device that moves up and down the length of the rotating mandrels. The resin is then cured at elevated temperatures and the finished pipe is removed from the mandrel.

Filament winding results in the highest fiber-to-resin ratio of the three fabrication methods and consequently offers the highest strength-to-weight ratio. This is the method used by Waco Boom.

 

 

Hand Lay-up

As the name suggests, hand lay-up is a manual fabrication process. It involves building up layers of chopped glass or woven glass mat impregnated with catalyzed resin around a suitable mold. Special metal rollers are used to improve glass wet-out and force out trapped air bubbles. Hand lay-up is generally used only for custom shapes or for large-diameter pipe where filament winding or centrifugal casting is not practical.

 

FRP Pipe Manufacturer & Supplier

Our Yongchang glass fiber reinforced plastic / FRP pipes are designed and manufactured according to customer requirements, with various sizes and configurations. We can manufacture pipelines of any specification and pressure and can be made into composite pipelines such as PVC/FRP, PP/FRP, PVDF/FRP, etc., according to the conditions of use. If you are interested in our products, please contact us for more information.

What is the difference between FRP and GRP?

FRP stands for Fiber Reinforced Plastic, a term commonly used in North America in the U.S. GRP is a term that means the same thing. However, it is commonly used in Europe and Asia to stand for glass fiber reinforced plastic.

 

What is fiber reinforced plastic/polymer (FRP)?

 

Fiber reinforced polymers consist of two main components; fibers and a polymer matrix. In FRP, the fibers are embedded in a polymer matrix. This structure provides chemical and physical properties that are completely different from the properties of the individual materials. In fact, these materials meet higher engineering requirements than ordinary materials. As a result, composites are used in less sophisticated very complex and demanding manufacturing tasks. The mechanical, civil, biomedical, marine and aerospace industries are the main users of composites.

 

The main role of fibers is to provide strength and stiffness to the material. However, the fibers alone are brittle (e.g., glass). Therefore, fibers are encapsulated in a polymer material coating. The polymer matrix holds the fibers in their position and transfers the load between the fibers. It also contributes to the interlaminar shear strength.

 

The following fibers are used in composites: E glass, S glass, quartz, aramid (Kevlar 49), Spectra 1000, carbon (AS4), carbon (IM-7), graphite (P-100) and boron. Polyester, vinyl ester, epoxy, bismaleimide, polyimide, and phenolic resins are the polymers used. Each polymer has different chemical and physical properties; therefore, contributes differently to the composite structure. As a result, the properties of the composites also vary from polymer to polymer.

 

Polyester and vinyl are low-cost materials and are therefore widely used in commercial applications. Epoxy resins are used in high-performance continuous fiber matrices. It also outperforms vinyl and polyester under high temperature conditions. Bismaleimide and polyimide are high temperature resin matrices used in temperature critical engineering applications. Phenolic resins are high-temperature resin systems with good smoke and fire resistance; therefore, they are used in aircraft interiors.

Fiber reinforced polymers consist of two main components; fibers and a polymer matrix. In FRP, the fibers are embedded in a polymer matrix. This structure provides chemical and physical properties that are completely different from the properties of the individual materials. In fact, these materials meet higher engineering requirements than ordinary materials. As a result, composites are used in less sophisticated very complex and demanding manufacturing tasks. The mechanical, civil, biomedical, marine and aerospace industries are the main users of composites.

 

The main role of fibers is to provide strength and stiffness to the material. However, the fibers alone are brittle (e.g., glass). Therefore, fibers are encapsulated in a polymer material coating. The polymer matrix holds the fibers in their position and transfers the load between the fibers. It also contributes to the interlaminar shear strength.

 

The following fibers are used in composites: E glass, S glass, quartz, aramid (Kevlar 49), Spectra 1000, carbon (AS4), carbon (IM-7), graphite (P-100) and boron. Polyester, vinyl ester, epoxy, bismaleimide, polyimide, and phenolic resins are the polymers used. Each polymer has different chemical and physical properties; therefore, contributes differently to the composite structure. As a result, the properties of the composites also vary from polymer to polymer.

 

Polyester and vinyl are low-cost materials and are therefore widely used in commercial applications. Epoxy resins are used in high-performance continuous fiber matrices. It also outperforms vinyl and polyester under high temperature conditions. Bismaleimide and polyimide are high temperature resin matrices used in temperature critical engineering applications. Phenolic resins are high-temperature resin systems with good smoke and fire resistance; therefore, they are used in aircraft interiors.

 

What is Glass Reinforced Plastic (GRP) / Glass Fiber Reinforced Plastic (GFRP)?

 

Glass Reinforced Plastic, commonly known as fiberglass, is a fiber reinforced polymer that contains glass fibers in a composite structure. The polymer is usually epoxy, polyester or vinyl. Fiberglass materials are commonly used in high performance recreational aircraft and gliders, boats, automobiles, bathtubs, hot tubs, water tanks, roofing products, pipes, cladding, castings, surfboards, and exterior door skins.

Glass Reinforced Plastic, commonly known as fiberglass, is a fiber reinforced polymer that contains glass fibers in a composite structure. The polymer is usually epoxy, polyester or vinyl. Fiberglass materials are commonly used in high performance recreational aircraft and gliders, boats, automobiles, bathtubs, hot tubs, water tanks, roofing products, pipes, cladding, castings, surfboards, and exterior door skins.

 

Yongchang is one of FRP pipe suppliers and produce FRP chemical tank, can be customized, flexible process, high anti-aging performance, excellent corrosion resistance, welcome to consult.