This lubricant is a water-based solid lubricant product formulated from natural flake graphite and water as main raw materials, compounded with additives such as antioxidants, extreme pressure anti-wear agents, and stabilizers. It exhibits excellent lubrication performance, high-temperature resistance, and extreme pressure resistance. The product can be used for hot rolling lubrication of seamless steel tubes and for lubricating the mandrels in continuous rolling mills during seamless steel tube production.