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For refractory manufacturers, the construction of castables is a problem in winter. Because it will involve the solidification and maintenance of castables, there are many process requirements and standard rules for construction at low temperatures. Mainly to do a good job of sealing, windproof, heating and warming the working environment, keeping the temperature of the lining after pouring above 5 ℃, the following Zhengzhou Anrui will come and give you a brief introduction.

Generally, the standard for winter construction is that when the average daily outdoor temperature is stable below 5°C for 3 consecutive days, the construction standard for refractory castables should adopt the winter construction standard. Before construction, the temperature of the working environment should be measured first, including the temperature of the outside air of the heating shed should not be less than 5 ℃, the temperature of the work place and the surrounding lining, the temperature of the material after heating in the heating shed, and the refractory injection material out of the tank , The temperature when entering the mold and curing, etc., full-time temperature measurement personnel should be set, should be measured every 4 hours and make a record.

Processing requirements of castable materials for winter construction:

1. The materials delivered to the construction site should have a quality certificate, effective inspection report and product instruction manual, and indicate the manufacturer's name, product name, brand name, weight, production date, and validity period. Before construction, the material should be visually inspected, and when in doubt, it should be sent to a nationally recognized laboratory for physical and chemical index inspection.

2. Before winter construction, the coarse and fine aggregates and powders used to prepare refractory castables should be prepared and stored in a warehouse with a cover on the top and a pad on the bottom, and should be kept dry. Materials should be placed according to specifications and varieties, and signs should be set up. The preparation of refractory castables should preferably use aluminate cement. Clean water should be used when stirring refractory castables.

Preparations for winter construction of refractory castables are:

1. Special construction plan for winter construction should be prepared before the construction of refractory castables, and technical disclosure should be carried out. After the acceptance of the previous process, the construction of the next process can be carried out.

2. Construction personnel should conduct special training for winter construction. The greenhouse and material heating facilities should be set up in time, and a special person should be set up to maintain. The mixer equipment should be installed near the pouring place. The gauge M and temperature measuring equipment shall be used after passing the test.

3. Simulate construction under the same conditions before construction to verify winter construction measures.

Castable winter construction process:

1. Mud, formwork and other materials should be transported into a warm shed for storage before construction. The mixing water should be heated, and the heating temperature should meet the following requirements: the water temperature of ordinary portland cement refractory castables of 42.5 and above should not exceed 60°C; the water temperature of aluminate cement refractory castables should not exceed 30°C.

2. Cement should not be directly heated. When the required temperature is still not reached after heating the water, the aggregate can be heated. The heating temperature of aggregates of ordinary portland cement refractory castables of 42.5 and above shall not exceed 40°C; the heating temperature of aggregates of aluminate cement refractory castables shall not exceed 30°C.

3. Aggregate can be heated by means of hot kang, exhaust pipe heating or steam, etc. It should not be directly heated by flame.

4. The refractory castables should be proportioned according to the specified mix ratio, and the measurement should be accurate. Cement, aggregate and powder should be measured by weight, and water and admixture solution can be measured by volume.

5. Stirring should be carried out in a greenhouse, and the ambient temperature should not be lower than 5℃. The mixing time should be in accordance with the construction instructions or product instructions. carried out. If there is no specific requirement for the mixing time, the mixing time should not be less than 3mm, and the total mixing time should not exceed 5mm. 6. The well-mixed refractory castable should be poured within 30mm, or within the specified time according to the product instruction manual. The refractory castable that has been set up shall not be used

7. Insulation measures should be taken for transportation equipment, and the number of loading and unloading operations should be reduced. Transportation equipment should be safe, firm and clean. 8. The pouring of refractory castables shall be carried out in accordance with the relevant provisions of the current national standard "Code for Construction and Acceptance of Industrial Furnace Masonry Engineering" GB50211. The temperature of the refractory castable before entering the mold should not be lower than 10℃. The temperature of the surface in contact with the refractory castable shall not be lower than 5°C.

8. After construction, the refractory castables should be maintained in the greenhouse under normal temperature maintenance regulations. During curing, the refractory casting body shall not be subjected to external force, vibration and load, and the curing temperature shall be stable. Before the initial setting of the refractory castable, it is advisable to apply pressure to the exposed surface for a second time, and it should be covered with plastic film and thermal insulation materials, and removed together when removing the mold.