steel hammock stand

2016-04-28 16:08:40  

 Have you ever noticed there're small pits or pores in the tube surface, which will get more legible after painted and make the stand's overall appearance looks low?

Have you ever get confused that under the same tube specification(same diameter and same thickness), why some stand's holding capacity is 450lbs  but the other's can reach 850lbs?

Why? Then knowing the difference between cold-rolled tube and hot-rolled tube will help you find the answer : 

1) When take manufacturing process into consideration, cold-rolled tube have two more process, milling and annealing. After get repeated milled and annealed, the tube surface gets more even,glossy and smooth. 

2) When take structure into consideration,cold-rolled tube appears to allow local buckling,which can make full use of bar-buckling of the bearing capacity, however the hot-rolled tube does not allow any local buckling occurs.  

3)When take raw material into consideration,under the same thickness requirement(take 2.3mm for example),2.3mm plates is enough for 2.3mm hot-rolled tube,but for 2.3mm cold-rolled tube, due to the repeated milling process, the plate needed should be thicker than 2.3mm.