What are the quality requirements and inspection methods for steel springboards
Steel springboard is an important type of steel, steel springboard is an important steel springboard indispensable in architectural design, steel springboard for quality requirements are relatively high, without good quality it is impossible to make the steel springboard has a better use. The quality requirements of steel springboard generally include both physical and chemical aspects. What are the common quality requirements for steel springboard and the common quality control methods? Together with the small edition of the steel springboard factory to discuss it:
(1) Quality requirements
① Chemical composition of steel: The chemical composition of steel is one of the most important factors affecting the performance of steel springboard, and is also the main basis for the formulation of pipe rolling process parameters and heat treatment process parameters of steel springboard.
a. Alloying elements: added intentionally, according to use
b. Residual elements: brought into steelmaking and properly controlled
c. Harmful elements: strictly controlled (As, Sn, Sb, Bi, Pb), gas (N, H, O)
Off-furnace refining or ESR: improve the uniformity of chemical composition and purity of steel, reduce the non-metallic inclusions in tube billet and improve their distribution.
② The geometric dimension accuracy and shape of steel springboard
a. Steel springboard outer diameter accuracy: depends on the diameter determination (reduction) method, equipment operation, process system, etc.
Allowable OD deviation δ=(d-di)/Di ×100% D: ****** or minimum OD mm
Di: nominal outer diameter mm
b. The wall thickness precision of the steel jump plate: it is related to the heating quality of the tube blank, the process design parameters and adjustment parameters of each deformation process, the quality of the tool and the lubrication quality, etc
Allowable wall thickness deviation: ρ=(S-Si)/Si×100% S: ****** or minimum wall thickness on the cross section
Si: Nominal wall thickness mm
