9245 جودة مواصفات الورقة

Hot rolled steels for manufacturing of line pipes for European onshore natural gas transmission

1. This grade is in development progress and orders are subjected to negotiation.
2. Elements not mentioned in this table shall not be added intentionally without purchaser's approval except for elements which may be added for deoxidation and finishing of the heat. In Erdemir practice for this grade max 60ppm Ca is added in order to inclusion modification.
3. For each reduction of 0.01% below the maximum carbon content an increase of 0.05% manganese above the specified maximum value is permitted with a maximum increase of 0.2%.
4. For product analysis if C % ≤ 0.12 then C equivalent formula, CE pcm % = C+(Si/30)+(Mn/20)+(Cu/20)+(Ni/60)+(Cr/20)+(Mo/15)+(V/10)+5B is applied. If B % < 0.0005 then B value shall not be taken into account in the formula given above and shall be accepted 0 (zero). For product analysis if C % > 0.12 then C equivalent formula, CEııw % = C+(Mn/6)+(Cr+Mo+V)/5+(Ni+Cu)/15 is applied. Carbon equivalent related to heat analysis is indicated in test certificate and also it is guaranteed in product analysis as an Erdemir practice.
5. Al/N≥ 2.
6. Unless otherwise specified, B is not added.

1. In Erdemir practice, test values apply to transverse specimens taken from the coil, although these test values apply to transverse specimens taken from the pipe body.
2. Rt0,5/Rm values aimed on hot band.
3. Rt0,5/Rm values aimed on hot band.
4. For impact test values are based on Table G.1 from related standart.
5. Impact test is not carried out under 6.00 mm thickness. For thicknesses in the range of T ≥ 6.00, CVN impact energy values are guaranteed as specifed in standart without applying CVN impact test, however CVN impact test may be performed "optionally" to meet CVN absorbed energy requirements of customer in case of negotiation. % Shear fracture area is not measured under 6.00mm thicknesses. For thicknesses equal or over 6.00mm, calculation of average shear fracture area is done "optionally" for pipes with diameter (D) ≤ 508mm. If pipe diameter (D) > 508mm or not specified calculation of average shear fracture area is not performed.
6. % Shear fracture are values are guaranteed subject to negotiation with performing DWTT providing % shear fracture area is equal or greater than 85% at 0ºC in all thickness, results are released as separated from test report.
7. There are some discrepansies (increase or decrease) between the test results, according to taken specimens from coil or pipe depending on diameter, type and direction of test taken from pipe. Therefore we advise our customers to consider this issue and determine the most suitable grade for their intended production accordingly. Mechanical properties which are specified in the above table for hot rolled bands are only guaranteed on the sample taken perpendicular to the rolling direction.