A hot dip galvanized pipe
| A Youfa hot dip galvanized steel pipe needs to go through 36 processes and 203 quality control points | ||||
| Youfa people always adhere to the principle of product quality no small matter, zero tolerance attitude to quality problems has been deep bone. From supplier selection, material selection, production to quality inspection and packaging, we strictly control the quality and try our best to meet the needs of customers | ||||
| Process | Control test items | Control the detection effect | Control and test links | Control inspection content |
| 1 | Selection of manufacturers | Ensure raw material manufacturer qualification and product quality | Raw material manufacturer evaluation | Comprehensive evaluation of quality, reputation and other aspects from well-known large domestic suppliers, raw material procurement to achieve "quality selection of raw materials" |
| Selection of the raw material | The raw material of welded pipe production directly affects the quality of welded pipe | Scar check | Avoid "tongue" or "scale", bonded, irregularly shaped raised metal sheets on the surface of the coil | |
| Crack detection | Avoid open tip bottom cracks on the surface of coil plate | |||
| Bubble check | Avoid small holes in the smooth inner wall of circular plate with irregular distribution and different sizes on the surface or inside of coil plate | |||
| Inspection of surface slag inclusion | Avoid non-metallic slag on the surface of the coil | |||
| Pitting check | Avoid small, irregular shaped pits and local rough surface on the surface of coil plate | |||
| Cut to check | Avoid straight and thin groove marks on the surface of coil plate | |||
| Scratch check | Avoid slight scratches on the surface of the coil that are straight or curved | |||
| Indentation check | Avoid the surface of the coil plate with different shapes, sizes, discontinuous dents | |||
| Roller check | To avoid the pressure roller damage, the surface of the plate periodically appear raised or depressed marks | |||
| Rusty spot check | Avoid yellow, yellow-green, or brown spots on the surface of the coil | |||
| Scale inspection | Avoid excessive area of red metal oxide layer on the surface of coil | |||
| Gone with the wind song check | Avoid bending in the longitudinal and horizontal direction of the coil | |||
| The waves to check | Avoid the bending shape of the full length or part of the coil along the rolling direction of the horizontal surface undulating and regular distribution of the protruding (wave peak) and concave (wave trough) | |||
| Groove check | Avoid the simultaneous curved bending of the coil along both lateral sides | |||
| Thickness check | Avoid uneven longitudinal and transverse thickness of coil | |||
| Burr inspection | Avoid sharp, thin flying spurs on both sides of the width of the coil | |||
| Folding check | To avoid creases or laps that cause sharp bending of the coil | |||
| The width of the test | Prevent width and uniformity not procurement requirements | |||
| thickness detection | To prevent the thickness and uniformity procurement requirements, and to achieve the "wall thickness assurance standard" | |||
| component analysis | Analyze C, Si, Mn, P and S according to standard, and compare the results with the incoming material list | |||
| mechanical test | The transverse or longitudinal tensile test of the coil | |||
| 2 | Raw material charging | Put in the coil plate, ensure that the coil plate, into the cage before the preparation | appearance inspection | Confirm the steel strip specification, wall thickness, material, measurement siz e, and put into production after qualified inspection |
| 3 | Steel pipe forming | Roller leveling To change the coil form from rough to fine (coil into a round tube)The raw material is centered with the roll | Roller leveling Molding quality inspection | Because the coil plate in the cage storage will appear bending, through the five rollers can be relatively flat To ensure the evenness and symmetry of the opening Angle of the welding seam, the opening Angle can be adjusted according to the pipe diameter. |
| 4 | High-frequency welding | Weld the coil in the shape of a cylinder firmly | Welding quality inspection | Adopt highly efficient and intelligent automatic solid-state high-frequency welding equipment to implement precise pressure welding to ensure the overall welding quality of steel pipe products. |
| 5 | Weld scraping scar | Cut and grind the remaining height of external weld | appearance inspection | Prevent the phenomenon of swiveling seam, free mouth and welding joint dislocation;Requires no corrugation of the weld and no weld nodules on both sides.If customers need, we can implement internal weld burr on line removal. |
| 6 | Steel tube sizing | Adjust outer diameter and unroundness of welded pipe | Outer diameter inspection | Within the range required by the customer |
| NDT(nondestructive testing) | Inspect the defects on the surface and inside of the weld that may affect the quality of the steel pipe | Adjust the instrument before testing | online testing by NDT | |
| 7 | Flying saw cutting | Setting cutting of butt-welded pipe | Pipe inspection | When the steel pipe is moving at high speed, the flying saw machine with the function of following tracking can cut the steel pipe in continuous motion |
| 8 | Pipe end keep | Dealing with the burr of the pipe mouth | Pipe inspection | Ensure that the pipe end is smooth and without burr, and ensure that each steel pipe can achieve the "net effect of straight pipe". |
| 9 | The pickling steel pipe | Remove sundries such as oxide scale generated on the surface of steel pipe | The concentration of the acid | Real-time monitoring, strict control of acid concentration and pickling time and other process parameters, fast and efficient removal of iron oxide and other impurities on the surface of the steel pipe, to ensure the quality of hot dip galvanized steel pipe |
| 10 | Hot-dip galvanizing | Rust protection | High stability, environmental protection hot spread galvanizing equipment | Each hot dip galvanized steel pipe production line have those equipment.On-line monitoring of zinc liquid temperature, zinc immersion time, internal and external blowing pressure and other important process parameters.Ensure the uniformity, consistency and stability of zinc layer |
| 11 | Passivation | Passivation process | real-time monitoring of passivation process | Each production team strictly control, real-time monitoring of passivation process key quality control points to ensure the effect of passivation film |
| 12 | Product packaging | Packed in accordance with the specified number of steel pipes per piece | Packing belt inspection | The packing of steel pipe is hexagonal. Automatic baler ensures that each steel pipe is neatly packed and beautiful |
Manufacture Procedures
Every piece of steel pipe can be traced to its source. YF-MES produces a lifetime unique identifier for each product, which can be traced back to the raw material manufacturer, production team, production date, material, wall thickness and zinc content.
- ERW steel pipe
- Hot-dipped galvanized pipe
- Hot-dipped galvanized square tube
- Oil and Gas pipe
- Ringlock scaffolding system
- Square/Rectangular tube
Electrical Resistance Welded Pipe Manufacture Procedures
Hot-Dipped Galvanized Steel Pipe Manufacture Procedures
Hot-Dipped Square/Rectangular Welding Steel Pipe Manufacture Procedures
Oil And Gas Pipeline Manufacture Procedures
Ringlock Scaffolding System(Ringlock Standard) Manufacture Procedures
Square/Rectangular Welding Steel Pipe Manufacture Procedures
