The refractory lining of the converter, when the furnace diameter greater than 1.3 meters, and conventional high magnesium aluminum brick masonry bricks in the inner diameter of the furnace; when the furnace diameter of less than 1.3 m, usually built into the ramming refractory lining. When beaten, the ends of the lining are higher than the middle, and the furnace is olive-shaped. This is conducive to precious metals concentrated in the central furnace and can pour out all the metal when it is poured. The lining material is preferably a high aluminum clinker having a high Al ₂ O _{3 content} . When the beating is placed, a wooden core is placed in the furnace, and the wooden mold is burned in the oven. The lining of the aluminum silicate refractory (ie high aluminum clinker) should be divided into the following two steps:
Low-temperature drying: heating to 225 ° C at a rate of 5 ~ 15 ° C / hour, constant temperature for more than 12 hours;
High-temperature heating: After drying, the temperature is raised to 500 ° C at a rate of 100 to 150 ° C / hour. Keep at a constant temperature for more than 9 hours and heat to the use temperature.

Speed sensors are machines used to detect the speed of a transport vehicle.