A fast method to calculate the sag of traverse! (Conscience Version) _ Sectional Drawing
Original title: a quick method to calculate the sag of conductor! (Conscience Edition) Part1 Apprentice On a certain day in a certain month in a certain year, Anyway, when I was an apprentice, Go to the construction site with the old comrades of the unit. The owner asked us to estimate the conductor sag of a certain gear. The old Comrade took out his calculator. After pressing a few times, He said the answer confidently. I was shocked at that time! In my perception, Isn't calculating the sag of a conductor supposed to be like this? Expand the full text Such a complicated formula, Shouldn't we use software to calculate? How can you figure it out with a calculator? After the meeting,titanium round bar , I consulted the old comrades. The old Comrade just said to me lightly: "Multiply the span squared by 7" Me: That's it? Old Comrade: This is it! I know that asking too many questions will expose my ignorance. So I didn't ask. In the dead of night, I opened the book secretly. I hope I can find the answer from the book. Part2 Sag Curve Template Finally, On page 216 of Overhead Transmission Line Design, I seem to have found the answer! Draw the key points! In the past,6al4v titanium bar , when there were no computers and no Dao Heng, The sagging curve of the plane section is drawn by hand. For ease of drawing, The designer defines the K value of the sag template, Use this value to make a sag template! Universal sag template And the value of K is: Combined with the maximum sag calculation formula: At the same time, the height difference of the hanging point is ignored (cosβ = 1). In other words: The calculation of the original sag is really: The square of the span multiplied by a value! Getting closer to the truth! Part3 Plan section Why is K equal to 7? Why not equal to 3, Titanium 6Al4V wire ,titanium sheet grade 5 , equal to 10, equal to 20? This is a problem! Wait! This K seems to have been seen somewhere. Right! Plane section!!! Bottom line: Original The K value can be output in the plane section diagram output by Dao Heng, However, his K value is slightly different from that in the textbook. But (in fact, Dao Heng has an option to choose): Namely: Next, let's test whether our reasoning is correct: As shown in the figure above, the span is 336m and K = 7.8891 Thus: f (sag) = 336 × 336 × 7.8891 × 10-5 =8.9 !!! The result is consistent with that of the plane section drawing! In short, let's divide the sag calculation formula into two parts, one is the K value of the sag template, and the other is the square of the span. Sag is calculated by multiplying the value of K by the square of the span. The K value can be queried in the plane section view. Part4 Regularity If the K value is often inquired through the plane section, First, it is possible that the project has not yet produced a plane section in the early stage. Second, it is inconvenient to carry inquiries with you. In fact, the value of K has a general range and law. If it is only a rough estimate, It's perfectly adequate. According to the query summary of the editor, The following rules are obtained: 1) The K value is independent of the power level. 2) The value of K has little to do with the type of conductor. 3) The icing affects the K value, and the larger the icing is, the larger the K value is. 4) The safety factor affects the K value, and the greater the safety factor, the greater the K value. In particular,titanium bar gr5 , the K value of the steel pipe pole line is very large. Sum up 1) General line K = 7 ~ 9 General line refers to: Conventional conductor, no icing, normal setting out (safety factor 2.5 ~ 3.0) 2) Iced line K ≈ 12 3) Steel pipe pole line K ≈ about 20 Source: Power Transmission Interesting Forum Return to Sohu to see more Responsible Editor:. yunchtitanium.com
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