What are the methods to achieve constant temperature in steel frame greenhouses?
The steel structure greenhouse has the advantages of simple structure, low construction cost, and fast construction speed, and is suitable for planting large-scale crops. At present, galvanized steel skeleton greenhouses are mostly used, which are easy to install and maintain, do not need top pillars, and have a long service life.
First, improve the insulating properties of the covering. After heavy snowfall, the snow must be removed from the roof of the shed in time to prevent the snow from getting wet after the snow melts and increase the bearing capacity of the shed. At the same time, adding plastic shed film can improve the insulation performance of the greenhouse.
At present, solar greenhouses basically use agricultural plastic shed film to cover the roof, use thermal insulation quilts (blankets, grass covers) outside the plastic shed film, store light in the morning after sunrise, and use a cover to cool down at night. However, the thickness of the plastic shed film is limited, and the temperature preservation is limited.
Although the insulation of the steel frame greenhouse has a certain thickness and density, its insulation performance has been greatly improved, but it can no longer meet the ideal requirements of solar greenhouse insulation in winter, especially after rain and snow, the insulation is humid, and the insulation performance is almost lost. . Cover the insulation layer with a complete layer of polyethylene longevity shed film. From the back slope of the greenhouse to the front drainage channel of the greenhouse, the slope wall at the back is aggravated and compacted with masonry (stone) for about 2 meters at regular intervals, and the front drainage The port can only be pressurized at both ends. After sunrise in the morning, roll up the insulation, and release heat after sunset to form a multi-layer insulation form of double-layer plastic shed film clip insulation, which prevents the direct intrusion of cold air at night and improves the insulation effect. According to practice, the room temperature in the greenhouse can be increased by 4°C and 6°C respectively.
The steel frame shed is lit and heated. If the crops cultivated in the greenhouse are affected by strong cold currents and the indoor nighttime temperature is lower than 6°C, they should be ignited and heated.
