1. Preparation before construction

• Material storage: Refractory plastic cannot be piled in the open air and should be stored in a cool warehouse. If the ambient temperature is below 10℃, cold protection measures need to be taken.
• Equipment commissioning: Install the forced mixer in place and test run normally.
• Cleaning the site: Before construction, the steel structure, baseline, holes and other parts of the furnace need to be fully inspected and accepted, and construction can only be carried out after passing the inspection. The construction department should clean up the debris in and around the furnace, and transport the air compressor, construction machinery and scaffolding to the site.

2. Mixing of materials

• Mixing ratio: Pour 100KG of bulk material into the mixer, add 8KG of liquid binder, and stir for more than 10-20 minutes. When the construction surface needs materials, add the coagulant, and then stir for another 10-20 minutes until the plastic meets the construction requirements.
• Addition of coagulant: The addition ratio of coagulant is 1 bag of plastic to 1 bag of coagulant. Depending on the ambient temperature, the addition ratio of coagulant can be adjusted appropriately.
• Note: Under the premise of ensuring the plasticity of the material, liquid binder should be added as little as possible to prevent the high-temperature performance of the material from deteriorating. Materials that are contaminated and have been stirred for more than 40 minutes should be discarded.

How to use refractory plastic

3. Laying, nailing and tamping

• Material transportation: The stirred materials must be transported to the working surface for construction as soon as possible, otherwise the materials will lose plasticity and be difficult to tamped.
• Laying method: Gather the materials into balls and press them into the pins with force. Lay them out one ball at a time like fish scales. The laying area should not be too large each time, and 0.5m² is appropriate. After laying, use a rubber hammer or a wooden hammer to tamp and compact it.
• Tamping requirements: Overlap 2/3 between hammers and 1/2 between rows, and repeat tamping 3-4 times. The tamping must be carried out continuously. If there is an interruption, the interface must be plucked or made into a step shape before construction.
• Anchor brick treatment: When encountering anchor bricks, ram the furnace wall plastic to the upper surface of the anchor brick, dig out part of the material at the location where the brick is installed, place the die, and drive it into the plastic. When the size of the anchor brick is reached, take out the die and install the anchor brick.
• Hole treatment: When encountering holes, it is necessary to lay them in layers and sections, and place the caulking materials according to the designed expansion joint position during the construction process, and the surrounding area should be carefully rammed and compacted.
• Furnace roof construction: When ramming the furnace roof, first support the template, then ram and compact it, and so on.

4. Surface finishing and expansion joint reservation

• Surface finishing: After the ramming of the refractory plastic is completed, scrape off the excess surface according to the thickness requirements of the furnace wall and flatten the surface. When encountering a thicker furnace wall, exhaust holes should be punched on the surface.
• Expansion joints: Expansion joints can be pre-clamped with 3mm thick plywood or cut after construction. The spacing of the expansion joints is 800x800mm, and the depth of the expansion joints is 2/3 of the thickness of the furnace wall. After the expansion joints are cut, 200x100mm strips should be rammed on the expansion joints to seal the expansion joints for the second time.
• Surface treatment: When the surface becomes dry, a wire brush can be used to remove the hair to expose the internal pores for easy removal of moisture. Use a breathable needle, i.e. a φ4mm steel chisel, to pierce the exhaust holes perpendicular to the working surface. The depth of the holes is about 1/3 of the thickness of the lining, and the center spacing of the holes is 150~250mm.

5. Maintenance

• Furnace: Refractory plastics are thermosetting materials and can be directly put into the furnace without maintenance.
• Quality inspection: After the construction is completed, quality inspection and acceptance are required. The inspection content includes whether the construction meets the design requirements, whether the structure is complete, and whether there are defects such as cracks, fragmentation, and shedding.

Through the above steps, the correct use of refractory plastics can be ensured, thereby ensuring the safe operation of high-temperature equipment.