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• source:metmac;
• Time:08/27/2021

Circular arc transition rectangular elbow material cutting   Line drawing:

The unfolded drawing adopts the triangle method to stake out, and each board is divided into several triangles for calculation and stake out. The output data is calculated according to the inner edge of the rectangle, and the material can be loaded and unloaded directly on the plate according to the data. When welding, it is welded on the outside. For details, please refer to the unfolding diagram to stake out according to the following method:

1 The drawing method of the front and rear panels:

(1). Draw an arbitrary straight line segment, the length is equal to La(1).

(2) According to the figure, draw an arc and intersect at one point with the two ends of the La(1) line segment as the center, and Lb(1) and m1 as the radius. Then use the intersection point and the left end point of the La(1) line segment as the center of the circle, and La(2) and m2 as the radius to draw the arc to intersect at another point, and draw each intersection point in the order of the figure. Connect each intersection to get the expanded view of the side panel.

(3). Because the upper and lower openings of the side plates are not necessarily in the same plane, sometimes it is necessary to bend in or out along the blanking line to be accurately spliced. The specific method is determined by the workers on the spot.

2 The drawing method of unfolding the upper and lower curved board:

(1). Draw an arbitrary straight line segment, the length is equal to w1.

(2). Draw the center line perpendicular to the w1 line through the midpoint of the w1 line, measure the length of sl1 (sl2) on the center line, and draw the w2 line parallel to the w1 line symmetrically through the taken point.

(3) Connect the two ends of w1 and w2 according to the figure to get the expanded view of the upper and lower curved plates. When assembling, the upper and lower curved plates must be respectively curled according to the upper and lower arcs of the side plates before assembling. The specific method is determined by the workers on site.

6. If you select ‘Add Side’ in the side selection, the basic shape of the expanded image will not change, the width will be wider than the original, and the height will increase by wt2. Please pay attention to the distinction when blanking.

2. Rectangular duct tube can be eccentrically deviated and right-angled elbow material cutting.    Cutting method for marking:

In the unfolded picture, the two sides of the board adopt the triangle method to stake out, and each board is divided into several triangles for calculation and stake out. The output data is calculated according to the inner edge of the rectangle, and the material can be loaded and unloaded directly on the plate according to the data. When welding, it is welded on the outside. For details, please refer to the unfolding diagram to stake out according to the following method:

1 The drawing method of unfolding the side panel: (The front side panel is an example, and the cutting method of the rear side panel is the same)

(1). Draw an arbitrary straight line segment, the length is equal to La(1).
(2) According to the figure, draw an arc and intersect at one point with the two ends of the La(1) line segment as the center, and Lb(1) and mp1 as the radius. Then use the intersection point and the left end point of the La(1) line segment as the center of the circle, and La(2) and mp2 as the radius respectively to draw the arc to intersect at another point, and draw each intersection point in the order of the figure. After connecting each intersection, draw a rectangle with length Lx and height h2 perpendicular to the La(n+1) line to obtain the expanded view of the side plate.
(3). Because the upper and lower openings of the side plates are not necessarily in the same plane, sometimes it is necessary to bend in or out along the blanking line to be accurately spliced. The specific method is determined by the workers on the spot.

2 The drawing method of unfolding the upper and lower curved board:
(1). Draw two parallel straight line segments, the distance is equal to sl1 (sl2), the length is w1, w2, and the center deviation of the two lines is w;
(2) Take the upper left point as the center of the circle (a<>
(3). Connect each end point according to the figure to get the expanded view of the upper and lower curved plates. When assembling, the upper and lower curved plates must be respectively curled according to the upper and lower arcs of the side plates before assembling. The specific method is determined by the workers on site.

3. Rectangular variable diameter two-way three-way material cutting     Stakeout method:
1. The lower mouth of this component is a horizontal rectangle, and the upper mouth is divided into two rectangular mouths with an inclination angle to the horizontal plane. The inclination and radius of the two upper mouths can take any value within a certain range, and the upper mouth and the lower mouth are transitioned by arc , The outer arcs of the two rectangular openings naturally intersect at one point. The length and width of the lower rectangular opening can be any value. The length and width of the two nozzles must be less than or equal to the length and width of the main pipe opening. Each rectangular opening can add a straight pipe section. Three links.
2. In the schematic diagram, L and w are the length and width of the inner side of the lower rectangular opening, L1, w1 are the length and width of the inner side of the upper right rectangular opening, L2, w2 are the length and width of the inner side of the upper left rectangular opening, R1, R2 are The turning radius of the inner side of the right and left branch pipes, a1 and a2 are the deflection angles of the right and left corners, h1 is the height of the straight pipe section of the main pipe, lp1 and lp2 are the lengths of the straight pipe sections of the right and left two branches, and b is the thickness of the plate. Requirements L>=L1, L2>0, w>=w1, w2>0, h1, lp1, lp2>=0, R1, R2, b>0, a1, a2 must be greater than the angle of the intersection and less than or equal to 90, If the input parameters do not meet the basic requirements of the component, please re-enter the parameters according to the prompts.
3. When the widths of the tee links, namely W, W1, and W2 are not equal, the components are processed by unilateral closing. The radius of the front plate elbow in the expanded drawing is calculated by the gradual change of the inner arc, and the outer radius By increasing the corresponding width of the inner circle radius, the turning angle is the same as the input angle. In this way, when the width and angle of the two branch pipes are the same, and the width of the main pipe is not much different, the error is very small. However, if the width and angle of the two branch pipes differ greatly, and the width of the main pipe differs greatly, there will be a length error of more than 1%. Therefore, it is required that the width, radius, and angle of the two branch pipes should be as consistent as possible when designing the tee, and the width of the main pipe should not be too far apart to ensure the accuracy of the cutting.
4. The unfolded drawing is drawn directly by the method of straight line and arc intersecting and tangent. All dimensions are cut according to the inner diameter of the component. If the edge addition function is used, the unfolded size already includes the edged size, and the user can follow the relevant positioning The size can be cut according to the drawing, and no detailed description will be given here.

4. Rectangular reducing four cross     The expanded drawing is drawn directly by the method of straight line and arc intersecting and tangent. All dimensions are cut according to the inner diameter of the component. If the edge addition function is used, the expanded size already includes the edged size, and the user can press according to the relevant positioning size.

5 Rectangular equal diameter M-shaped elbow material cutting off   R2 in the expanded diagram is calculated based on the value of R1, that is, R2=R1+h. The expanded diagram is drawn directly using a straight line and arc tangent method. All dimensions are cut according to the inner diameter of the component. If the edge addition function is used , The expanded size already includes the size of the border, the user can download the material according to the picture according to the relevant positioning size 