Detailed information
Composite/FRP purlins box section
Composite/FRP purlins box section is a hollow section with a square or rectangular cross-section. The product can be used as purlins, secondary frames, bracing bars, or components according to drawings once the load and connection have been checked. The image on the page is an actual product photo provided by Hưng Thịnh Phát; the dimensions, thickness, and length of each order need to be confirmed separately.
Performance needs to be evaluated according to product documentation
- Limit rust: FRP does not form rust like carbon steel, suitable to consider for humid environments, saltwater, or corrosive agents.
- Low mass: Convenient for transportation and handling, but load capacity should not be inferred solely from weight.
- Chemical resistance: Depends on resin system, concentration, temperature, and exposure time; must refer to compatibility table or testing.
- Electrical properties: FRP usually has high resistance, but it is only considered an electrical safety solution when there are test indicators and appropriate system design.
- Fire properties: the base resin is an organic material; fire retardant or flame spreading requirements must use the correct material grade and corresponding test report.
Application of FRP box bars
Fence and enclosing frame
Box bars have a neat surface, suitable for use as columns, crossbars, or auxiliary frames for fences. The design must account for wind load, column spacing, height, base plate, and screw details to limit cracking at drilled holes.
Fish rafts and aquaculture cages
FRP material has been studied for marine aquaculture cages. However, using these box bars for fish rafts requires a dedicated design for wave loads, impacts, fatigue, buoyancy, connections, and operating conditions; product descriptions should not replace specialized calculations.
Coastal works
In areas with salt vapor, FRP can be considered for secondary frames, fences, and some inspected components. It is necessary to select the appropriate resin system and UV protective layer, seal cut surfaces after processing, and avoid using incompatible metal parts.
Warehouses, factories with corcorrosion factor
The Composite bars can reduce the need for anti-rust painting in certain applications. Before using them in chemical plants, fertilizer facilities, water treatment, or corrosive environments, the chemical names, concentrations, temperatures, and exposure times must be provided for evaluation.
Items requiring lightweight materials
Low weight helps reduce transportation and handling effort. For load-bearing components, deflection is usually a condition that needs careful inspection; do not replace steel bars with FRP bars based on direct size ratio.
Note design, processing, and installation
- Check load capacity, support span, orientation of the cross-section, and deflection limits before selecting the specification.
- Use the characteristic table of the correct product; do not take parameters from adifferent FRP brand to calculate for this product.
- Drill, cut with appropriate tools, vacuum dust, and use protective equipment to control fiber dust.
- Arrange hole and edge spacing, washers/plates large enough; do not over-tighten bolts causing bar wall crushing.
- Seal bar ends and cut surfaces according to technical instructions to protect fiber cores.
- Check UV, temperature, fire, electrical, and chemical requirements using test records applicable to the correct configuration.
Information needed to send for a quotation
- Drawings or cross-sectional dimensions, lengththickness and length.
- Purpose of use, span, and expected load.
- Environment: outdoors, coastal areas, salt water, chemicals, temperature.
- Quantity, cutting/drilling/processing requirements, color, and surface.
- Delivery location and required schedule.
Hưng Thịnh Phát accepted for manufacturing and supplying according to confirmed specifications. Send request for Composite purlins quotation or call 0338 72 7742 to discuss with the sales department.
Frequently asked questions
Can Composite purlins directly replace steel purlins?
Direct replacement with the same size should not be done. FRP has directional mechanical properties and an elastic modulus different from steel, so load, deflection, stability, and connections must be recalculated.
Do Composite purlins resist all types of chemicals?
No. Chemical resistance depends on the resin system, concentration, temperature, and exposure time. It is necessary to refer to the compatibility table or test the sample under actual conditions.
Product is non-conductive and non-flammableno?
These two absolute assertions should not be used. Electrical and fire criteria must be based on the test report of the correct product and comply with the safety design of the structure.
