How to calculate the force that the weld can bear
Calculation formula
(reinforcement replacement calculation formula
checking calculation of bending capacity (strength):
the basic calculation formula of normal section bending capacity of single reinforcement rectangular section flexural member is:
m ≤ Mu = FYAs (Ho FYAs / 2a1fcb)
weld form
(1) according to different weld joint forms, it can be divided into two types There are five kinds of weld, including butt weld, fillet weld, plug weld, groove weld and end weld
1) butt weld. The welding seam between the groove surfaces of the weldment or between the groove surface of one part and the surface of another part
(2) fillet weld. The weld seam welded along the intersection line of two orthogonal or near orthogonal parts3). The weld that forms the end joint
4) plug weld. Two parts are overlapped, one of which has a round hole, and the weld formed by welding two plates in the round hole is not plug welding if only the angle constant seam is welded in the hole
5) groove weld. The two plates are overlapped, one of which has a long hole, and the weld of the two plates is welded in the long hole
if this kind of welding seam is automatic welding, considering the influence of stress, the stress performance is about 90 ~ 96% of the original (some brittle metals have slightly lower resistance to external force)
Calculation formula
calculation formula of reinforcement replacement
checking calculation of flexural capacity (strength):
the basic calculation formula of flexural capacity of normal section of single reinforcement rectangular section flexural member is:
m ≤ Mu = FYAs (Ho FYAs / 2a1fcb
when the concrete strength grade exceeds C50, the, A1 is the section strength of 1.0
steel bar after replacement:
fy2as2 (ho2-fy2as2 / 2fcb) ≥ fy1as1 (ho1-fy1as1 / 2fcb)
extended data
when welding, the physical quantities (such as welding current, arc voltage, welding speed, line energy, etc.) selected to ensure welding quality are called welding process parameters. The influence of process parameters on the weld shape is as follows:
(1) when other conditions remain unchanged, with the increase of welding current, the weld thickness and reinforcement increase, while the weld width almost remains unchanged (or slightly increases)
(2) when other conditions remain unchanged, the arc voltage increases, the weld width increases significantly, while the weld thickness and reinforcement decrease slightly.
(3) when other conditions remain unchanged, the weld width, weld thickness and reinforcement decrease with the increase of welding speed
welding current, arc voltage and welding speed are the three main welding process parameters. When selecting, we should consider the appropriate cooperation among these three parameters to get a good shape and meet the requirements of the weld
1. The weld thickness can be used as the plate thickness
The thickness of Q345B steel is 6-16mm, and the temperature is 170Mpa within 200 ℃. It can be substituted into the calculation When the force is less than P > 3 and 10N = 1kg, two plates with the same thickness are made of steel. It is known that the length is 100 mm, the thickness is 8 mm, and the thickness of steel is 1[ δ t] It is 167mpa The solution is derived from the formula F σ= ----- ≤[ σ T] get l δ 1 F ≤ L δ one σ T = 133.6 (KN) L-100 mm δ 1—8mm δ T-167mpa A: the weld can bear 133.6 (KN) tensile force
MPa It represents the maximum ability of a metal material to resist failure under tension. The calculation formula is:
0 σ= FB / so
where: FB -- the maximum force on the specimen when it is pulled to break, n (Newton); So -- original cross-sectional area of sample, mm & # 178
tensile strength (RM) refers to the maximum stress value of the material before breaking. When the steel yield to a certain extent, e to the rearrangement of internal grains, its resistance to deformation increases again. At this time, although the deformation develops rapidly, it can only increase with the increase of stress until the stress reaches the maximum. After that, the ability of steel to resist deformation is obviously reced, and a large plastic deformation occurs at the weakest point, where the cross section of the specimen shrinks rapidly, necking phenomenon occurs, and finally fracture occurs. The maximum stress value of steel before tensile fracture is called strength limit or tensile strength
unit: n / (kg force per unit area)
in China, the universal material testing machine is widely used to measure the tensile / compressive strength of materials
for brittle materials and plastic materials without necking, the highest tensile load is the fracture load, so the tensile strength also represents the fracture resistance. For necking plastic materials, the tensile strength represents the resistance to the maximum uniform deformation and the ultimate bearing capacity of the material under static tension
for parts such as wire rope, tensile strength is a significant performance index. Tensile strength is easy to measure and has good reprocibility. It has a certain relationship with other mechanical properties such as fatigue limit and hardness. Therefore, it is also used as one of the conventional mechanical properties to evaluate proct quality and process specification
selv calculated!