Setting-out method of 9-degree elbow with tin sheet:

Draw a straight line with the length π (d-t) (d-outer diameter of circular tube, t-plate thickness). Divide the line segment into 16 equal parts, .1.2.3 ... 16. Setting out from two elbows with equal straight angles: Yn=r cosα.

Yn=1/2(d-2t)cosα when ≤α n ≤ 9? When 9 <: Yn=1/2dcosα when α n ≤ 18? Where Yn—— refers to the coordinate value from the equal point of the circumferential length of the expansion diagram to the curve;

r—— radius of auxiliary circle; D—— outer diameter of circular tube; T-plate thickness; α n-auxiliary circle bisecting angle; For pipes with a diameter of 3mm, n can be selected as 16. α1=36°/16=22.5° 、α2=45°、α3=67.5°、α4=9°、α5=112.5°、α6=135°、α7=157.5°、 α8=18°?

Steps for setting out the Arabian Circle:

1. Draw the side view and the top view according to the actual size, and then divide the 1/4 arc on the top view into three parts. Then connect the separated points (1, 2, 3, 4) with the F point by straight lines (A, B, C, D). (Steps correspond to Figure 1-1 and Figure 1-2)?

2. Draw a straight line again, take a point I, measure the height dimension and mark a point J on the straight line with the point I as the starting point. Then draw a line perpendicular to it through point I, measure the length of straight line A and mark a point K on the line with point I as the starting point. Then measure the length of straight line B and mark a point L on the straight line with point I as the starting point. Connect two points of K J with straight line E, and then connect two points of L J with straight line F. (Steps correspond to Figure 1-3)?

3.

① Draw a P Q straight line with the length of one side of the square head, find the center point O of the P Q straight line and draw a line perpendicular to it. ?

② Draw an arc on the vertical intersection line with point Q as the center and straight line E as the radius (hereinafter referred to as Qe arc) to intersect at point 7, and connect the two points of 7 Q with a straight line. ?

③ Draw an arc with point Q as the center and straight line F as the radius (hereinafter referred to as Qf arc). Then measure the chord length between point 1 and point 2 in the top view (hereinafter referred to as 1 ~ 2 chord length) as the radius, draw an arc with point 7 as the center and intersect with point 6, and connect the two points of 6 Q with a straight line. ?

④ Draw an arc with point 6 as the center and chord length of 1 ~ 2 as the radius to intersect with Qf arc at point 5, and connect the two points of 5 Q with a straight line. ?

⑤ Draw an arc with point 5 as the center and chord length of 1 ~ 2 as the radius to intersect Qe arc at point 4, and connect the two points of 4 Q with a straight line. ?

⑥ Draw an arc with point Q as the center and point P as the radius, then draw an arc with point 4 as the center and point Q as the radius to intersect with point S, and connect the two points of Q S with a straight line. Then connect point 4 with point s with a straight line. ?

⑦ Draw an arc with point S as the center and point 4 as the radius (hereinafter referred to as S4 arc), and then draw an arc with point S as the center and straight line F as the radius (hereinafter referred to as Sf arc). ?

⑧ Draw an arc with point 4 as the center and chord length of 1 ~ 2 as the radius and intersect Sf arc at point 3, and connect the two points of 3 S with a straight line. ?

pet-name ruby draw an arc with point 3 as the center and chord length of 1 ~ 2 as the radius and intersect Sf arc at point 2, and connect two points of 2 S with a straight line. ?

⑩ Draw an arc with point 2 as the center and chord length of 1 ~ 2 as the radius to intersect S4 arc at point 1, and connect 1 S two points with a straight line. ?

4. Draw an arc with point 4 as the center and point O as the radius (hereinafter referred to as O4 arc), and then draw an arc with point S as the center and the length of two points O and Q as the radius (that is, 1/2 side length) to intersect with O4 arc at point T. Connect two points of S T with a straight line, and then connect point 1 with point t with a straight line.

5. Connect 1 2 3 4 5 6 7 with line segments in turn to get the 1/2 expansion diagram.

6. If you want to develop the picture completely, you can draw the other half continuously according to the above steps (steps correspond to 1-5)?

Extended information:

1. Because most pipe fittings are used for welding, in order to improve the welding quality, the ends are all turned into grooves with a certain angle and a certain edge. This requirement is also strict, and the thickness of the edge, the angle and the deviation range are stipulated. The surface quality and mechanical properties are basically the same as those of pipes. For the convenience of welding, the steel grade of pipe fittings and connected pipes is the same.

2, that is, all pipe fittings should undergo surface treatment, and the iron scales on the inner and outer surfaces should be sprayed off by shot blasting, and then coated with anticorrosive paint. This is for export needs, moreover, in order to facilitate transportation and prevent corrosion and oxidation at home, we must do this work.

3. It is the requirement for packaging. For small pipe fittings, if exported, it is necessary to make wooden boxes, about 1 cubic meter. It is stipulated that the number of elbows in this box should not exceed about one ton. This standard allows suits, that is, large sets are small, but the total weight should generally not exceed one ton.

for large y, it needs a single package, and for 24 ",it needs a single package. The other is the packaging mark, which indicates the size, steel number, batch number, manufacturer's trademark, etc.

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