Description

Key Features:

KD-WSF-Ft-STI-C is an outdoor non-expansive fireproof coating for steel structures, formulated with hydrocarbon fire resistance that has passed domestic fire testing. It is a pioneering product for outdoor fireproof applications, offering technical performance that exceeds the requirements of the GB14907-2018 standard for outdoor non-expansive fireproof coatings for steel structures.

Substrate Treatment and Application Methods:

1. Substrate Treatment:

1.1 Surface Treatment for Steel Structures:

a. New Ordinary Steel Structures: – Sandblast and remove rust from the steel structure surface, followed by applying a compatible anti-rust and anti-corrosion coating. We recommend using an epoxy zinc-rich primer followed by an epoxy cloud iron intermediate coat system.

b. Galvanized Steel Structures: – To ensure good adhesion with the fireproof coating, it is necessary to use an epoxy coating transition paint after surface treatment.

c. Old Steel Structures or Old Primed Surfaces: – If the primer is undamaged and the surface is clean, check for compatibility between the fireproof coating and the primer. If there is no primer or the primer is significantly damaged, it must be repainted after rust removal.

1.2 Before Construction:

• Thoroughly inspect the steel components for rust protection coating, dust, oil residue, cracks, and inadequate welding. Proceed with construction only after confirming there are no issues.

1.3 Steel components that have not undergone rust protection treatment must be treated accordingly. (Generally, this step is the user’s responsibility.)

2. Base Layer Construction:

Base layer reinforcement is required for coating application. Different methods are used:

a. Welding Wire Mesh: – Weld steel rebar pins using No. 4 lead wire or 4mm diameter steel rebar pins, bent into an “L” shape with a height of about 4cm. Weld them onto the steel components with approximately 40cm spacing between them. – Pay special attention to welding at the acute and obtuse angles of the steel structure.

b. Attaching Mesh: – First, cut the steel plate mesh to a suitable length based on the actual steel structure conditions. – When attaching the mesh, ensure it conforms to the acute and obtuse angles of the steel structure, with an approximate gap of 8-15mm between the mesh and the steel structure. – Overlap the mesh by at least 30mm.

c. Direct Mesh Attachment: – Steel columns’ coating reinforcement can also use wire mesh. After applying the base layer to the steel structure, apply the wire mesh when the coating thickness reaches approximately 10mm. Cut the wire mesh to a suitable width based on the steel structure’s diameter (width). Typically, create a 10cm overlap, secure it by burning the wire ends, and ensure it is fixed.

3. Fireproof Coating Application:

a. First Layer – Scratch Coat: – Mix the coating in a ratio of coating powder to scratch coat adhesive = 2:1 (by weight), adding an appropriate amount of water during batching to suit the on-site application conditions. Apply this layer using either spray or roller methods with a thickness of 1-3mm.  – Allow the scratch coat to dry completely (usually, over 24 hours at room temperature) before applying the next layer.

b. Subsequent Layer Coating Ratio: – Fireproof coating powder to water = 1:0.8-1.2 (by weight). The amount of water added during batching can be adjusted based on the on-site application conditions to facilitate work.

c. Application of Second Layer and Beyond: – The second layer can be applied using spray or trowel methods. When using the trowel, ensure that there is no occurrence of hollow spots and maintain a slightly rough surface texture for better adhesion with the layer below.

d. Layer-by-Layer Application: – Start the next layer (after the first) when the previous layer is about 70-80% dry (usually after 24 hours). Each layer should be 6-8mm thick, proceeding until the desired fire protection design thickness is achieved.

e. Wire Mesh Application: – When the coating thickness reaches approximately 10-15mm, embed steel wire mesh, overlapping it by 5-10cm. Use a trowel to press the mesh in one direction, ensuring firm attachment along edges, corners, and connections. – For coating thicknesses of approximately 21-25mm, embed fiberglass mesh fabric (or carbon fiber mesh) in the same manner.

f. Slope for Pipe Supports and Steel Beam Top Portions: – Create a slope of 30°-45° on the top of the coating at the pipe supports and steel beam top portions. After the coating is completely dry, use outdoor-type sealant to seal the tops.

4. Self-Inspection: After the completion of the fireproof coating, a self-inspection can be conducted primarily for thickness and appearance.

• Thickness Check: Use a homemade probe to mark the thickness and check different areas of the steel structure. Promptly repair any areas where the thickness does not meet the requirements.
• Appearance Check: Examine the surface of the fireproof coating for cracks and hollow areas. Address and repair any such issues promptly.

5. Maintenance:

• After applying the fireproof coating, protect it from rain, vibrations, and exposure.
• For cured products, water curing or other maintenance methods can be used, where possible.

Coating Application Precautions:

1. In regions with significant temperature variations, steel components must be treated with a metal mesh. For humid coastal areas, protective measures for the fireproof coating should be implemented.
2. Avoid applying this product in temperatures below 5°C during winter or when the surface temperature of the construction base exceeds 50°C (ambient temperature ≥35°C) during summer.
3. When working during the rainy season, take measures to protect the newly applied fireproof coating.
4. Operations should be avoided when wind speeds exceed 5m/s or during rainy weather when there is condensation on the component surfaces.
5. If there is a need to interrupt the fireproof coating application or perform repairs, a slope of 30°-40° should be created as a connecting surface for the next application or repair. Clean and moisten the slope before starting work.
6. During transport and storage, protect the fireproof coating from rain and moisture. Do not use the coating if it has solidified into clumps.
7. After each round of application, promptly clean the equipment and tools used.
8. When working in environments with overlapping tasks, pay attention to safety precautions.