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Production principle of steel bar connection sleeve


Steel bar rolling straight thread connection method

1. Scope of application

The equal-strength threaded joints (rolling) of steel bars are suitable for all concrete structural projects with seismic fortification and non-seismic fortification, especially for important structures that require full use of the strength and ductility of steel bars.

1.1 thick diameter, different diameter steel connection.

1.2 Connection of bent steel bars and super long horizontal steel bars.

1.3 Butt joint of reinforcement cage.

1.4 The butt joint between two fixed steel bars.

1.5 Connection of steel structure and reinforcement. When the shaped steel column intersects with the main reinforcement of the beam, the reinforcement can be connected with the nut welded on the steel plate.

2. Process principle

The principle of the straight thread connection of steel bars is as follows: the end of the steel bar is pressed into a circle by a roller, and the thread and the sleeve are threaded to form a mechanical joint of the steel bar at one time.

There are six types of straight thread joint connections: (reduced diameter type, flared type will not be introduced here)

2.1 The possible free rotation of type I connection (standard type joint) use. The reason for using iron bars is opposite each other to lock the endpoint strength of the bridge piece. Willing to choose standard sleeve or reduced diameter connecting sleeve.

2.2 Type II connection (extended joint)

It is used in occasions where the steel bars are too long and dense, and it is inconvenient to rotate.

The connecting sleeve is fully screwed into the lengthened thread of a steel bar in advance, and then screwed back into the end thread of the connected steel bar, and the connecting piece can be locked by rotating the steel bar half a turn, and a standard connecting sleeve can be selected.

2.3 Type III connection (locking female connector)

It is used for the mutual docking of reinforcement cages such as bent steel bars, bridges, cast-in-situ piles, etc. that cannot be rotated at all.

Screw the lock nut and the connecting sleeve into the extension thread in advance, and then screw it into the end thread of the other steel bar, and lock the connecting sleeve with the lock nut. Standard or flared connection sleeve and lock nut can be selected

2.4 Type IV connection (positive and negative screw connection)

It is used in occasions where the steel bar cannot be rotated at all and the internal force of the steel bar is required to be adjusted, such as construction joints, post-casting belts, etc.

Connecting sleeve with positive and negative wire

It is used in occasions where the steel bar cannot be rotated at all and the internal force of the steel bar is required to be adjusted, such as construction joints, post-casting belts, etc.

The connecting sleeve has positive and negative thread buckles, which can loosen or tighten two steel bars in one screwing direction. The connecting sleeve with positive and negative thread buckles should be used first.

3. Construction sequence

3.1 Rebar end cutting.

3.2 The end of the steel bar is rounded.

3.3 Roll the thread while pressing the circle.

3.4 Use the connecting sleeve to butt the steel bars.

4. Operation points

4.1 The end of the steel bar should be straightened before cutting. The end face of the cut should be perpendicular to the axis of the steel bar.

4.2 Water-soluble cutting coolant shall be used for cooling the rolling head of the rolling mill, and oil coolant shall not be used for threading. The thread pattern of the steel bar and the thread pattern of the connecting sleeve should be intact. If there are any irregularities on the surface of the thread pattern, it should be removed. See Table 1, Table 2, and Table 3 for the technical parameters of the end thread and the sleeve.

Table 1 Dimensions of steel bar end thread rolling processing (mm)

Nominal diameter of threaded steel bar Φ14 Φ16 Φ18 Φ20 Φ22 Φ25 Φ28 Φ32 Φ36 Φ40

Table 2 Connection sleeve specifications and dimensions (mm)

Nominal diameter of threaded steel bar Φ14Φ16 Φ18 Φ20 Φ22 Φ25 Φ28 Φ32 Φ36 Φ40

Thread outer diameter 21.5 25 27 30 32 37 41 47 53.5 59

Socket length 38 42 4752 57 60 67 75 85 90

Table 3 Connecting sleeve thread specifications and dimensions (mm)

Nominal diameter of threaded steel bar Φ14 Φ16 Φ18 20 Φ22 Φ25 Φ28 Φ32 Φ36 Φ40

Pitch 2.0 2.5 3.0 3.5

Tooth angle 75 60

4.3 After passing the self-inspection, the steel wire head should be put on the protective cover or the connecting sleeve connected with it immediately, and the plastic protective cover should be installed on the other end of the connecting sleeve for protection.

4.4 When installing, first install one end of the connecting sleeve on the end of the basic steel bar and tighten it in place with a pipe wrench, then guide the centering clamp to clamp the connecting sleeve, center the steel bar to be connected through the center hole of the guiding clamp, and screw it Tighten into place in the nipple to complete the connection. Remove the tools for inspection at any time, correct the unqualified ones immediately, and paint the inspected symbol on the socket if it is qualified.

5. Materials and equipment

5.1 The steel bars used for pier thickness shall meet the requirements of the national standard "Hot Rolled Ribbed Steel Bars for Reinforced Concrete" (GB1499) and "Reinforced Concrete with Waste Heat Treatment Steel Bars" (GB13014).

5.2 The casing and lock nut should be made of high-quality carbon structural steel or alloy structural steel, and the material shield should meet the requirements of GB699.

5.3 Equipment: cutting machine, rolling mill, common wrench. See Table 4 for the basic parameters of the GYS ?40 threading machine.

Table 4 Basic parameters of rolling mill

Item unit parameter value

Applicable to the nominal diameter of the processed steel bar mm Φ18, Φ20, Φ22, Φ25, Φ28, Φ32, Φ36, Φ40

Applicable processed steel bars comply with GB1499

Speed r/min 41, 28

Clamping operating torque Nm ≤30

Tractor operating moment Nm ≤30

Motor power KW 3

Power supply 380V 50HZ

Dimensions (1 table) mm 1100×600×1200

Machine weight kg 400

Shanghai Hufeng Machinery Co., Ltd. specializes in the production of steel bar joints, steel bar straight thread sleeves, and steel bar connectors. It has complete qualifications, and its tensile strength has reached the national first-class standard. Welcome to consult and negotiate.