Technological Process of Production and Quality Control in Procedures

ANSHAN THE THIRD STEEL ROLLING CO., LTD.

Production Process Chart

1. Material: After material was transported into our factory, we must have an inspection of weight, geometry size, chemical constituents according to ASSZ.ZY-02 the cargo inspection rules of billet. To the qualified billets, we will divide them into different standard and marked them by the material and specifications. (Two QC staffs will be responsible to the inspection and supervision)
2. Blanking: According to customers' demand, we'll choose the related specification to arrange the preparation of rolling, at the same time; we'll make the inspection according to the file of YB/T002-91 the permitted deviation of billet, measurement, appearance and weight for the first time rolling. The surface of the billet couldn't have slag and folding. Scratch, bump and pit are permitted to have. But they can't be more than the tolerance. If there are such defects which should be dealt with, the billet can't have welded part. Once found, they will be considered as waste.
3. Furnace: The billet is put into furnace by steel pushing machine. During the process of putting the billet into the furnace, they should be placed neatly; there should be no inclusions between billets. When receiving the putting signal, we must check seriously, and then we can drive the car. When receiving the stopping signal, we must stop immediately. The billet should comply with the number of the furnace; casting and ladle. The same one can't be interrupted. Once the signal is changed, we must set the separated mark (brick, iron etc.). The reheated steel should go with their original number.
4. Heating: The released temperature must be controlled from 1200℃ to 1500℃. The released temperature is tested by skill assessment measurement. Then the billet will come into the process of average temperature. Report the side temperature making the billet have the treatment among to the average. (Three QC staffs are going to work in 24 hours who will be divided into three parts to have the inspection and supervision)
5. Rolling: Choose the different roller to roll, according to different types of products. Roughing mill adopts Up-pressure to roll. There are three types of roller diameters 430mm for the top roller; 425mm for the mid-roller and 420mm for the bottom roller and total difference between min and max is more than 10mm. The middle rolling machine and finishing rolling machine should adopt almost the same rollers. The max difference should be less than 3 mm. The max value of difference between the two neighbor rollers is 8mm. Any preparation work should be done before the roller changing. Before using the rollers, the people should check the rolling track and gauge. The rollers can't be used if any defect exists as follows.
(1) There is direction, transverse direction crack in the surface.
(2) The trachoma
(3) Be unqualified to prick the slot demission or there be no a hardness tier.
(4) Grave roller neckwear.
(5) The petal wears roller head plum away or hurts till 1/2 insufficient C three QC from Quality Control Department in three shifts to supervise and inspect in 24 hours (every hours).
6. Cutting in Certain Length: The certain length should be adopted to cut according to the different customer's requirement. The saw bit should be installed firmly. The pressure pieces should be tightened strongly. Safety cover should be solid reliably. Respond to every part bolt, if safety device reliable, affirm errorless but begin examining hot saw machine detailed before starting up. When the effectuation saw is eager, the fixed length is accurate. Straight on the head necessary finished product excision, ensures that the corresponding standard demands.(Three QC from Quality Control Department in three shift to supervise and inspect in 24 hours).
7. Cooling: After cutting, the steel should go to cooling machine to do the cooling treatment. Before going into the machine, the steel should be straightened and nicely put. The max of steed temperature is 250 ℃ if the steel goes into the machine( 3QC from QCD in three shift to supervise in 24 hours).
8. Alignment: After cooling, the different aligning machine should be chosen for the steel to align to meet the requirement of straightness. The size of the steel to be aligned should no more than the maximum of capacity of the machine.
Before the trial run all of the connecting equipments and the safety cover should be in good condition and any problem happened should be solved in time. (3QC from QCD in 3 shifts to supervise in 24 hours)
9. Holes drilling and shooting: Drill and shoot holes on the drilling and shooting machine according to the requirement of customers. (3 QC from QCD in 3 shifts to supervise in 24 hours)
10. Testing and Checking: According to the roles mentioned by the customers, the chemical mechanical and dimensional test should be all up to standard. Being checked in batch, the max of batch is 300T (The light rail should be less than 200T). The smelting No, the size and dimensions should be the same in every batch, should be checked again. If any parameter is not up to the standard, this batch of product can't be delivered. But if these products are reclassified, the testing can be made again.
(1) Sampling and chemical Analysis
One sample should be chosen from every smelting No. for the chemical analysis of C. Mn. Si. P .S. The testing method should meet the requirement GB223.68-89, GB222-84.
(2) Tensile property
According to the rules GB2975-1998, we select correspond samples. We choose two for the property (), and choose other two samples of the same size for the craft test. The test is made on the 60T tensile machine whose grade is WE-60t, the test is made under the rules of GB700-88, YB (T) 65-87, YB (T) 24-86.
(3) The appearance size test
PLs refer to GB706-88, 222-3
The length is tested by tape measure
The sample position is more than 500mm from the end.
Check up tool: caliper, sample (made according to the correspond rules), ruler, micrometer.
The quality of surface is checked by sight, fulfill the rules of correspond standard.
(4) Ultrasonic quality inspection
The product is checked by QC specialist of quantity department on the Ultrasonic quality line, if there is any defect, it is selling.
11. Packing: pack the goods according to the rules GB2101-89.
For the packing material, we can choose hot rolling coil strip or reinforcing steel bar, for the packing of middle type production, must use the hot rolling material of more than 6.5mm.
The steel must be packing on the base frame, the lines should be perpendicular with the vertical, A packing unit can't be loose, is not allowed to be more than 2.5T. And the goods on the top should be put reasonable and clearly. (To be checked and monitored by a QC specialist in the quality department)

Raw Material