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Prestressing strand manufacturing

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 Prestressing strands is high tensile strength steel. The tensile strength of prestressing strands can reach up to 1860 Mpa. the process of manufacturing prestressing steel differs significantly from the conventional reinforcement. 

Figure 1


The process of manufacturing strands will begin by de-scaling the raw material (wire rod). The purpose of de-scaling is to remove the iron oxides (mill scale) from the surface of the wire rod. after removing the mill scale, the wire rod's surface is coated with a textured coating to enhance the adherence of lubricants to the raw material surface. The most commonly used coating is zinc phosphate. 

Figure 2


The wire rod then passed through a series of dies. The process of reducing the wire rod diameter is known as cold-drawing. In this process, the wire rod is drawn through a die with the required diameter. To prevent the wearing of dies, the wire rod will be drawn through a lubricant box. the lubricant will coat the wire with a thin layer that prevents the premature wearing and damaging of the die. 
The wire rod's cross-section will be reduced by 85%, and the tensile strength will increase by almost 50%. The tensile strength of the wire rod is approximately is 1180 Mpa. after drawing, the wire tensile strength increase to 1860 Mpa. after the completion of the drawing of 7 wires, the stranding process will start. The strand will consist of 7 wires, one wire will be at the center, and 6 wires will be wrapped around the center wire. 
Figure 3

After completing the wounding of wires into strands, the strands will be thermo-mechanically treated by subjecting the strands to continuous heating of 375 C while under tension at 40% of the ultimate tensile strength. This process will relieve the residual drawing stresses and reduce the relaxation of strand losses.  


  


Comments

  1. Sapcon Steels Pvt LtdMarch 7, 2021 at 11:21 PM

    You have provided a richly informative article about Prestressing strand manufacturing. It is a beneficial article for me. Thanks for sharing this information here.Top Steel Dealers India

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    You've shared some excellent material. I'm grateful for this post because it contains a lot of useful information. Thank you for sharing this piece of writing. Steel Buildings Ontario

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  7. barathkumar99kDecember 27, 2022 at 2:27 AM

    Great post! TMT rods are a vital construction material that provides strength and durability to buildings and structures. It's important to invest in high quality TMT rods to ensure the safety and longevity of the project. I appreciate the information provided about the different grades and sizes available. It's always helpful to have a variety of options to choose from. I also remember the Civil Contractors In Chennaialso provides a professional service similar to this.

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  8. Writer JordanMarch 1, 2023 at 4:44 AM

    Thank you for sharing about the strand manufacturing. The figures you used here shows the advancement of CAD drawing Services.

    ReplyDelete

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My name is Mohammad Hamdan, and I am a Civil/bridge Engineer with extensive professional background and experience in the field of construction. I have 10+ years of experience in the construction field. During my professional career, my emphasis has been placed on structural projects, mainly bridges, infrastructure and roads. Reading and practicing the design of structures is my passion.i was lucky to be a part of a big team that executed major highway interchanges. I believe in spreading the knowledge, thus, i compose these courses to share my experience and knowledge. My course focuses on the practical side of construction field. On other word, i am sharing some of what new engineers need to know about construction field. Beside working on construction field, i love writing some articles on my website ( curious civil engineer) Moreover, i wrote some engineering papers, you can check them  by searching my name on Google (Mohammad mamon Hamdan)