Many people are not familiar with thread reinforcement, but many people do not know about it. In fact, finish-rolled thread reinforcement is a kind of straight steel bar with discontinuous external threads in a special shape. At arbitrary section, the steel bar is able to stop connection or anchorage with internal threads. The threaded steel bar used in prestressing concrete is also known as the finely rolled threaded steel bar.
Prestressed concrete is classified by the yield strength of threaded steel bars, which is coded as "PSB plus the minimum regular yield strength". P, S and B are the first letters of Prestressing, Scres-thread and Bars respectively. The contract for ordering should include at least the following contents. On the one hand, it is the code number, product title, product strength grade code, specification and weight, as well as special requirements.
As for the allowable deviation of finely rolled threaded steel bars, the steel bars are usually delivered according to the fixed length. The detailed delivery length should also be specified in the contract. Sawing and reprocessing can be stopped according to the length requested by the demander. When the steel bars are delivered according to the fixed length or by the length of the ruled bar, the allowable deviation of the length is 0-50 mm. The allowable deviation of the length of the reprocessed steel bar is from 0 to + 20 mm. The bending degree of reinforcing bars should not affect the normal operation. The bending degree of reinforcing bars per meter should not be greater than 4 mm, and the total bending degree should not be greater than 0.4% of the total length of reinforcing bars. The end of reinforcing bars should be even, without affecting the passing of connectors.
The grade and chemical composition of the finely rolled rebar and the content of sulphur and phosphorus in the melting analysis of the rebar steel are not more than 0.040%. Consumer factories should also stop the selection and application of chemical composition and alloy elements to ensure that the waste rebar processed by different methods can meet the relevant mechanical properties requirements. Steel is also smelted in oxygen converters or electric furnaces. In the delivery state, steel bars are delivered in straight strip in hot rolling state, waste heat disposal state or heat disposal state after rolling.
Above is our introduction to the relevant theoretical knowledge of finely rolled rebar. Later, there will be more comprehensive introduction of relevant knowledge. I hope to give you some assistance.