Bunk beds, also known as apartment beds, are double-decker beds made primarily of cold-rolled steel sheets. They are commonly found in student dormitories, construction sites, and company dormitories. Their structure includes uprights, beams, and guardrails, connected using CO2 shielded welding. The surface is treated with degreasing and pickling for rust prevention and wear resistance. They use a hook-and-loop connection method for easy assembly and disassembly. The typical dimensions of a bunk bed are 200 cm long * 100 cm wide * 160 cm high, with the lower bunk 45 cm off the ground and the upper bunk 150 cm high. The materials used fall into three categories: square steel tubing, round steel tubing, and ordinary angle iron. Approximately 50 million bunk beds of various types are used in schools, businesses, construction sites, and other locations in China.
This type of bed developed with industrialization needs from the 20th century onwards. Early versions were mostly made of angle iron, but later, round and square tubing were gradually used to improve safety. Modern manufacturing processes emphasize the irregular rolling of cold-rolled steel sheets, with column thickness reaching 1.2mm. Anti-slip textures are added to stair treads, and welding processes must avoid porosity defects. After 2010, manufacturers introduced reinforced columns and higher guardrails, and extended paint life through electrostatic powder coating technology, expanding product applications to hotels, businesses, and other settings. Modern bunk beds not only prioritize practicality but also incorporate more design elements and personalized functions, such as storage cabinets and bookshelves, resulting in more diverse styles. With increasing environmental awareness, future bunk bed production will place greater emphasis on the environmental friendliness and sustainability of materials, such as using recycled or low-carbon steel. With technological advancements, future bunk beds may incorporate more intelligent elements, such as smart sensors and automatic adjustments.