The main performance and characteristics of weldable sleeve connection
1. Reliable connection quality and fast construction speed;
2. The quality of welded joints meets the industry standard "General Technical Specifications for Mechanical Connection of Reinforced Bars" JGJ107-2010 medium and high level------Class I joint performance requirements.
General requirements
1. Weldability The sleeve is welded with low-carbon alloy structural steel 20Cr material with good weldability to ensure the reliability of its welding quality. Its geometric dimensions and welding technical parameters refer to the welding sleeve technical parameters and sleeve welding technical parameter instructions respectively.
2. It is required that trained welding technicians hold certificates to perform welding operations in accordance with the welding seam design book, welding process qualification and inspection plan.
Welding process
1. Remove the plastic protective cover on the sleeve;
2. Spot weld one end of the large chamfer to the steel column. During welding, 2 points should be welded symmetrically, and the gap between the sleeve and the steel column should be about 2mm
Carry out welding along the chamfer of the short sleeve for one week to the specified welding seam requirements (see Figure 2);
4. After the welding is completed, the construction personnel should check the appearance quality of the welds one by one;
5. Requirements for weld appearance quality
(1) Check whether there are air holes, slag inclusions, cracks, arc craters, welding spots, etc., and repair welding in time if any defects are found;
(2) The shape of the weld seam should be uniform, full, and excessively smooth, and the difference between the height of the weld seam surface should not exceed 2mm within any 25mm length of the weld seam;
(3) The size of the welding leg should meet the requirements, and the deviation is 0~3mm.
6. Appearance quality inspection method
(1) Beat the weld with a small metal hammer to check whether there are air holes or slag inclusions, cracks, arc craters, welding tumors, etc., and repair welding in time if defects are found;
(2) Use a caliper to measure whether the height of the weld seam meets the requirements, and visually inspect whether the weld seam is full without any lack of meat, the shape of the weld seam should be uniform, and the weld seam should be smoothly transitioned.
Connection process
1. Remove the protective cap of the steel bar on the head of the steel bar;
2. Screw the qualified wire head into the short sleeve;
3. Tighten the steel bars with a wrench, and the tightening torque should not be less than the requirements of "Technical Specifications for Stripped Rib Rolled Straight Thread Connections of Steel Bars" Q/JY16-20140.
Inspection
1. According to the requirements of JGJ107-2010 in the "General Technical Specifications for Mechanical Connection of Reinforced Bars", carry out torque inspection on the screwed steel bar joints.
2. Carry out visual inspection of the weld seam, the weld seam should be connected and full, and the shape and height of the weld seam should meet the requirements.
The welded joints that pass the self-inspection shall be inspected randomly by the on-site quality inspector. Under the same construction conditions, the joints of the same grade, type, and specification of the same batch of materials shall be used for inspection and acceptance of 500 inspection batches produced in connection with each other. , less than 500 are counted as one inspection lot.
For each inspection batch of welded joints, randomly select 15% and no less than 10 of the engineering structures under construction to inspect their appearance quality.
The passing rate of random inspection of welded joints on site shall not be less than 95%. When the passing rate of sampling inspection is less than 95%, another same number of welded joints shall be selected for re-inspection. When the total passing rate of the two inspections is not less than 95%, the batch of products is qualified. If the qualified rate is still less than 95%, all joints shall be inspected one by one, and the unqualified welds detected shall be reinforced.
3. Unidirectional tensile test
(1) Process inspection: Before construction, the process inspection of short sleeve welding should be carried out, and the inspection requirements should be in accordance with "General Technical Specifications for Mechanical Connection of Reinforced Bars" JGJ107-2010.
(2) During the construction process, a unidirectional tensile test shall be carried out on the welded joints of the weldable sleeve. For each specification, 500 joints shall be used as an inspection batch for inspection and acceptance. Under the same welding conditions, three test pieces shall be tested for unidirectional tensile testing. Tensile test, the strength of the specimen should meet the performance requirements of grade I joints in JGJ107-2010 "General Technical Specifications for Mechanical Connection of Reinforced Bars".
(3) Requirements for the test piece: the test piece shall be welded on the steel plate with a short sleeve. Steel plate size: 200*200mm for steel plates above 32mm, 150*150mm for steel plates below 28mm; the thickness of the steel plate should be the thickness of the actual steel column profile; the material of the steel plate is the same as the steel column; the steel plate can be replaced by a steel column profile or profile.
1. Reliable connection quality and fast construction speed;
2. The quality of welded joints meets the industry standard "General Technical Specifications for Mechanical Connection of Reinforced Bars" JGJ107-2010 medium and high level------Class I joint performance requirements.
General requirements
1. Weldability The sleeve is welded with low-carbon alloy structural steel 20Cr material with good weldability to ensure the reliability of its welding quality. Its geometric dimensions and welding technical parameters refer to the welding sleeve technical parameters and sleeve welding technical parameter instructions respectively.
2. It is required that trained welding technicians hold certificates to perform welding operations in accordance with the welding seam design book, welding process qualification and inspection plan.
Welding process
1. Remove the plastic protective cover on the sleeve;
2. Spot weld one end of the large chamfer to the steel column. During welding, 2 points should be welded symmetrically, and the gap between the sleeve and the steel column should be about 2mm
Carry out welding along the chamfer of the short sleeve for one week to the specified welding seam requirements (see Figure 2);
4. After the welding is completed, the construction personnel should check the appearance quality of the welds one by one;
5. Requirements for weld appearance quality
(1) Check whether there are air holes, slag inclusions, cracks, arc craters, welding spots, etc., and repair welding in time if any defects are found;
(2) The shape of the weld seam should be uniform, full, and excessively smooth, and the difference between the height of the weld seam surface should not exceed 2mm within any 25mm length of the weld seam;
(3) The size of the welding leg should meet the requirements, and the deviation is 0~3mm.
6. Appearance quality inspection method
(1) Beat the weld with a small metal hammer to check whether there are air holes or slag inclusions, cracks, arc craters, welding tumors, etc., and repair welding in time if defects are found;
(2) Use a caliper to measure whether the height of the weld seam meets the requirements, and visually inspect whether the weld seam is full without any lack of meat, the shape of the weld seam should be uniform, and the weld seam should be smoothly transitioned.
Connection process
1. Remove the protective cap of the steel bar on the head of the steel bar;
2. Screw the qualified wire head into the short sleeve;
3. Tighten the steel bars with a wrench, and the tightening torque should not be less than the requirements of "Technical Specifications for Stripped Rib Rolled Straight Thread Connections of Steel Bars" Q/JY16-20140.
Inspection
1. According to the requirements of JGJ107-2010 in the "General Technical Specifications for Mechanical Connection of Reinforced Bars", carry out torque inspection on the screwed steel bar joints.
2. Carry out visual inspection of the weld seam, the weld seam should be connected and full, and the shape and height of the weld seam should meet the requirements.
The welded joints that pass the self-inspection shall be inspected randomly by the on-site quality inspector. Under the same construction conditions, the joints of the same grade, type, and specification of the same batch of materials shall be used for inspection and acceptance of 500 inspection batches produced in connection with each other. , less than 500 are counted as one inspection lot.
For each inspection batch of welded joints, randomly select 15% and no less than 10 of the engineering structures under construction to inspect their appearance quality.
The passing rate of random inspection of welded joints on site shall not be less than 95%. When the passing rate of sampling inspection is less than 95%, another same number of welded joints shall be selected for re-inspection. When the total passing rate of the two inspections is not less than 95%, the batch of products is qualified. If the qualified rate is still less than 95%, all joints shall be inspected one by one, and the unqualified welds detected shall be reinforced.
3. Unidirectional tensile test
(1) Process inspection: Before construction, the process inspection of short sleeve welding should be carried out, and the inspection requirements should be in accordance with "General Technical Specifications for Mechanical Connection of Reinforced Bars" JGJ107-2010.
(2) During the construction process, a unidirectional tensile test shall be carried out on the welded joints of the weldable sleeve. For each specification, 500 joints shall be used as an inspection batch for inspection and acceptance. Under the same welding conditions, three test pieces shall be tested for unidirectional tensile testing. Tensile test, the strength of the specimen should meet the performance requirements of grade I joints in JGJ107-2010 "General Technical Specifications for Mechanical Connection of Reinforced Bars".
(3) Requirements for the test piece: the test piece shall be welded on the steel plate with a short sleeve. Steel plate size: 200*200mm for steel plates above 32mm, 150*150mm for steel plates below 28mm; the thickness of the steel plate should be the thickness of the actual steel column profile; the material of the steel plate is the same as the steel column; the steel plate can be replaced by a steel column profile or profile.