Reaction-bonded silicon carbide square beams are suitable for the load-bearing structural frames of tunnel kilns, shuttle kilns, double-layer roller hearth kilns, and other industrial furnaces. This product offers high load-bearing capacity at elevated temperatures, does not bend or deform during long-term use, and has a service life several times longer than that of materials made from other substances. It is an ideal kiln furniture for industries such as sanitary ceramics and electroceramics. The product features high thermal shock resistance, oxidation resistance, and high-temperature flexural strength, maintaining its shape over prolonged use. It significantly reduces energy consumption without increasing the weight of the kiln car.