How many patterns are there for rebar What are the thread specifications?

According to the shape of the transverse rib, the rebar has three patterns: herringbone, spiral and crescent-shaped.

Rebar is a common name for hot-rolled ribbed steel bar, which belongs to small section steel and is mainly used for the skeleton of reinforced concrete building components. In use, it is required to have a certain mechanical strength, bending deformation performance and process welding performance. The raw material billets for the production of rebar are carbon structural steel or low-alloy structural steel that has been sedatively smelted, and the finished steel bars are delivered in hot-rolled, normalized or hot-rolled condition.

Threaded reinforcement is ribbed reinforcement, and ribbed reinforcement includes threaded reinforcement. Rebar with ribbed surface, usually with 2 longitudinal ribs and transverse ribs evenly spaced along the length. There are three types of transverse ribs: spiral, herringbone, and crescent.

Due to the action of the rib, it has a greater bonding capacity with concrete, so it can better withstand the action of external force.

There are two commonly used classification methods for types of rebar: one is to classify by geometric shape, according to the cross-sectional shape of the transverse rib and the spacing of the rib is different for classification or classification, such as the British standard (BS4449), the rebar is divided into type, type. This classification mainly reflects the gripping performance of the rebar.

The second is to classify (grade) by performance, for example, in China's standard (G B1499), rebar is divided into 3 grades according to the strength level (yield point tensile strength); In the Japanese Industrial Standard (JI SG3112), rebar is divided into 5 types according to its comprehensive properties; The British Standard (BS4461) also specifies a number of grades for rebar performance tests. In addition, rebar can also be classified according to use, such as ordinary steel bar for reinforced concrete and stressed steel bar for heat treatment of concrete. Main Applications:

It is widely used in the construction of civil engineering such as houses, bridges, roads, etc.

I know of three types: herringbone, spiral, and crescent-shaped patterns. Welding requirements vary.

Here is a spec sheet of some common standard sizes for metric threads:

1. The thread diameter is, and the pitch per millimeter is.

2. The thread diameter is 2mm, and the pitch per millimeter is.

3. The diameter of the threaded trousers is and the pitch per millimeter is.

4. The thread diameter is 3mm, and the pitch per millimeter is.

5. The thread diameter is 4mm, and the pitch per millimeter is.

6. The thread diameter is 5mm, and the pitch per millimeter is.

7. M6X1: The thread diameter is 6mm, and the pitch per millimeter is 1mm.

8. The thread diameter is 8mm, and the pitch per millimeter is.

9. The thread diameter is 10mm, and the pitch per millimeter is.

10. The thread diameter is 12mm, and the pitch per millimeter is.

The three elements of the thread:

1. Number of threads: The number of spirals forming threads is called the number of threads. There are single threads and multi-threads, and the multi-threads are evenly distributed within the profile perpendicular to the axis.

2. Pitch and guide spine sales:

The distance between adjacent teeth in the axial direction of two points on the mid-diameter line is called the pitch. On the same spiral line, the distance between the two adjacent teeth corresponding to the axial direction of the two points on the middle diameter of the Hu trace is called the lead. The relationship between the number of lines n, the pitch p, and the lead s is: s=n p.

3. Rotation direction: Looking along the axis direction, the thread that rotates clockwise becomes the right-handed thread, and the thread that rotates counterclockwise is called the left-handed thread. If the thread is vertically viewed, the visible part of the thread rising to the left is a left-handed thread, and the visible part rising to the right is a right-handed thread<>

Threads are divided into triangular threads, rectangular threads, trapezoidal threads, and zigzag threads according to their cross-sectional shape (tooth shape).

Among them, the triangular thread is mainly used for the connection (see Threaded Connection), and the rectangular, trapezoidal and sawtam threads are mainly used for transmission. The threads distributed on the outer surface of the parent are called external threads, and those on the inner surface of the matrix are called internal threads.

The thread formed on the cylindrical matrix is called the cylindrical thread, and the thread formed by the return on the conical matrix is called the tapered thread.

The main investigation is the mechanical properties such as tensile strength, as long as the tensile strength and other mechanical properties can be used any material.

Grade A3, Q235, Q195 and other low-carbon steels.

All materials from class Q235 are acceptable and do not require heat treatment.

Grade: Thread diameter below 16mm, 35 quenched and tempered heat destroys the beam.

More than 16mm, 45 and low-carbon gold and steel quenching and tempering treatment Of course, medium carbon alloy steel is better, but it is a waste of materials. Such as 10b21

Grade: Medium carbon alloy steel, quenched and tempered, heat treatment, 35crmo, 40cr, etc.

Is the material of the pattern plate the same as the rebar The difference is: the relationship between the snail pattern steel and the pattern steel is the relationship between the inclusion and the inclusion of the limb. Rebar, also known as secondary steel bar, is mainly composed of 16mn, which is widely used in concrete structures; Patterned steel includes Lishan rebar, slub steel and patterned plates, among which slub steel is also known as high-quality carbon alloy steel, which is widely used in prestressed concrete structural components; The pattern plate is mainly low carbon steel, which is generally used for trenches and well pool covers, and has a good anti-skid function.