What are the factors that affect the minimum bend radius?

Affects the minimum bend radius.

The main factors are:

Mechanical properties of the material.

The better the plasticity of the material, the greater the allowable deformation degree of the outer fiber, the smaller the allowable minimum bending radius; If the plasticity is poor, the minimum bending radius becomes larger. Plate.

The state also has a great influence on the bend radius, with hard or cold-work hardened materials having a large minimum bending radius allowed.

Bend line direction. When the direction of the bending line is perpendicular to the direction of the fiber, the minimum bending radius is small. When the two are parallel, the minimum bend radius is large.

Sheet surface quality and side quality. When the surface and side quality of the plate is poor, it is easy to produce stress concentration.

and reduced plasticity cause premature failure of the material, so a large bending radius should be used. If the sheet metal is not deburred, the burr side (direction) can be placed on the punch side, which can also improve the bending deformation forming limit and reduce the possibility of cracks on the outside of the part.

The magnitude of the bending angle. When the bending angle is small, the deformation area is not large, so the deformation degree of the middle section of the fillet can also be reduced, and the corresponding relative bending radius can be smaller. The smaller the bending center angle, the more the deformation of the middle section of the fillet is reduced, so the minimum bend radius can be smaller.

Effect of sheet width. When the wide plate is bent, the outside of the material is due to the friction with the die.

If it is large, the possibility of the material flowing in the opposite direction along the width of the plate is small, and the possibility of outer cracks is also greater, and the relative bending radius should be larger.

Bending die clearance. The small gap also makes it difficult for the fibers to flow on the outside of the material, which also makes the bending radius smaller.

The relationship between the radius of the circular curve and the degree of curvature: the radius of the curve = times the diameter.

The radius of curvature is mainly used to describe the degree to which a curve changes at a certain point.

For example, the curvature on a circle is the same everywhere, so the radius of curvature is the radius of the circle; The straight line is not curved, and the radius of the circle tangent to the straight line at that point can be arbitrarily large, so the straight line has no radius of curvature, and the larger the radius of the circle, the smaller the shape. The less bend, the more like a straight line. Therefore, the larger the radius of curvature, the smaller the curvature and vice versa.

Railway. Because the complex curve will increase the difficulty of survey and design, construction, maintenance and repair, and reduce the stability of train operation and the comfort of passengers, the complex curve should not be set up in new railways. Under difficult conditions, in order to reduce the reconstruction project, the complex curve can be retained for the reconstruction of the existing line; The second line in parallel with it can also be used if there is sufficient technical and economic basis. In a circular curve section, in order to overcome the centrifugal force generated by the train running on the curve.

There are many factors that affect the value of the minimum relative bending radius of the sheet, the main ones are:

1) The mechanical properties and heat treatment status of the material. The mechanical properties and heat treatment state of the material have a great influence on the value of the minimum relative bending radius, and the material with good plasticity is allowed to have a smaller bending radius. Therefore, in the actual production, the materials are made hard and sold cold, and their plasticity is improved by heat treatment methods to obtain a smaller bending radius and increase the degree of bending deformation; Or for metal materials with low plasticity, the method of heating bending is used to improve the degree of bending deformation.

2) The bending center angle of the bending part The bending center angle is the central angle corresponding to the arc of the rounded deformation area of the bent part. Theoretically, the curved deformation area is limited to the fillet area, and the straight-edged part does not participate in the deformation. However, due to the mutual tension of the materials, the straight edge close to the fillet also participates in the deformation, expands the range of combustion in the bending deformation zone, disperses the bending strain concentrated in the fillet part, and slows down the tensile state of the outer surface of the deformation zone, so that the reduction is conducive to reducing the value of the minimum bending radius.

3) The metal sheet used for stamping in the direction of the bending line is generally cold-rolled steel plate, and the sheet material is also fibrous. Sheets exhibit different mechanical properties in the transverse, longitudinal and thickness directions. Generally speaking, the tensile strength of the steel plate in the longitudinal direction (rolling direction) is better than that in the transverse direction (width direction), so the bending line is perpendicular to the rolling direction, and the bending line is parallel to the rolling direction, the allowable minimum bending radius is larger.

4) The quality of the surface and side of the sheet metal affects the blank used for bending is generally obtained by punching or cutting, and the defects such as burrs, cracks and cold work hardening on the shear surface of the material, as well as scratches and cracks on the surface, will cause stress concentration during bending, so that the material is easy to crack. Therefore, when the sheet with poor surface quality and cross-sectional quality is bent, the value of the minimum relative bending radius is larger. (5) The relative width of the bent part is the greater the relative width of the bent part, the greater the flow resistance of the material along the width direction.

Therefore, the relative bending radius of the narrow plate beam with a small relative width can be smaller.

a.Material strength.

b.Workpiece width.

c.Which part thickness is carried by the worker.

d.Bending the radius of slow cultivation.

Zhengchun Fufu true answer: ABCD

Summary. Hello dear, glad to answer for you! Causes the bending radius of the bending part to increase The bending radius increases.

The bending angle changes. The main factors influencing rebound. Mechanical properties of the material.

The higher the yield point of the material, the smaller the elastic modulus and the greater the flexural elastic jumpback.

Hello dear, glad to answer for you! The original cluster that causes the bending radius of the bending seepage to become larger due to the increase in the bending radius. The bending angle changes.

The main factors that affect the rebound. Mechanical properties of the material. The higher the yield point of the material, the smaller the elastic modulus and the greater the flexural elastic jumpback.

Hello dear, glad to answer for you! Bending is that it is not straight. It can be divided into deformation bending and spatial bending. When the rod is subjected to an external force perpendicular to the axis of the rod or a force couple in the plane of the axis, the axis of the rod changes from a straight line per mu to a curve.

The minimum bending radius that can be bent without damage to the material.

The minimum bend radius is defined as the minimum bend radius at which the hose operates without damage or significant loss of life.

The bending radius of the hose in operation should be checked to ensure proper hose use.

The hose bend radius should detect the inside surface of the bent section as follows:

Recommended minimum bend radius.

This can be found in the hose information or in the ** table, and for the minimum bend radius not listed, please consult the customer service manual.

The minimum bend radius for all dimensions is drawn on the gauge.

To determine the size of the bend radius, place the gauge on the inside of the bend of the hose, find the best fit curve, and read it.

If the inside bend radius is not available, you can use the outer bend radius, but you must subtract the outside diameter of the hose from the measured data.

The radius of curvature of this question is 2v 2 roots and 3g under the root

Vector decomposition of acceleration and combined with centripetal acceleration company, the specific method is as follows:

The radius of the number of bent hand holes is generally not less than the (bib) times of the diameter of the trembling finger.

Correct answer: 6