Certificates

WYJ048-2006 

1, general provisions

Build100000 cubic meters of oil floating roof used 12 MnNiVR (including 12 MnNiVR-SR) quenching and tempering high strength steel plate, besides shall meet GB19189-2003 "pressure vessel with the quality high strength steel plate" the basic requirement, still must conform to the relevant provisions of the technical conditions, when both requirement not consistent, to which the stricter standard. The technology conditions of all the standard reference, which shall be is the latest version.

2、referencedtechnical specifications1）GB19189     《With the pressure vessel of high strength steel plate》

2）GB/T709     《Hot-rolled steel plate and steel with size, shape, weight and allow deviation》

3）GB/T222       《Chemical analyses of the steel with specimen sampling method and finished product chemical composition allow deviation》

4）GB/T2975    《Steel and steel products mechanical test sampling location and samples preparation》

5）JB4730       《Nondestructive Testing of Pressure equipments

》

6）GB6397      《Metal tensile test sample》

7）GB/228       《Metal tensile test method》

8）GB/229       《metal charpy impact test method》

9）GB/232       《Metal bending test method》

10）JB4744-2000  《Steel pressure vessel products welding test plate mechanics performance of the test》

11）JB4708-2000  《Steel pressure vessel welding procedure qualification》

12）JB/T4709-2000《Welding specification for steel pressure vessels

》

3、chemical composition

12MnNiVR(include 12MnNiVR-SR)The chemical composition of the steel plate (melting analysis) should be in accordance with table 1.

Table 1  Chemical composition (melting analysis)

 

C	Si	Mn	P	S	Mo	V	Ni	Cr
0.06～0.14	0.15～0.40	1.20～1.60	≤0.020	≤0.010	≤0.30	0.02～0.06	≤0.40	≤0.30

note：1）Welding crack sensitive coefficient（Pcm）≤0.24。

Pcm(%)=C+Si/30+Mn/20+Cu/20+ Ni/60+Cr/20+ Mo/15+V/10+5B％

2）carbon equivalent（Ceq）≤0.44。

Ceq(%)=C+Mn/6+Si/24+Ni/40+Cr/5+Mo/4+V/14

3）Allow the other outside the watch add micro alloying elements. But the steel plate must be noted in the quality certificate。

4）Product analysis and melting analysis of deviation should be consistent with the provisions of the GB / 222。

4、The mechanical properties and the process performance

4.1 for 32 mm thickness and 28 mm 12 MnNiVR (including 12 MnNiVR-SR) steel, steel plate should be according to the finished product to tensile test, cold bending test and impact test one piece by another ; Other 12 MnNiVR steel rolling steel plate tensile test by the cold bending test and impact test one after another. The axis of the sample direction should be verticalthe rolling direction, Gap pay-off axisof charpy v impact test direction should verticalthe rolling surface of steel plate. sampling location According to the sampling location table 4 regulation, test results should comply with the provisions of the table 2.

Table 2  mechanical property

 

mechanical property		12MnNiVR （include 12MnNiVR-SR）
tensile strength  Rm(N/mm2)		610～730
Yield Rel(N/mm2)		≥490
elongation  A(%)		≥17
yield ratio（note 1）		≤0.91
cold impact test		b=2a  180°d=3a
Charpy impact test energy note 2）	Three average（J）	≥80
	Single minimum（J）	≥56
	Test temperature（℃）	-20
	Sample size and shape	2mmVtype

 

Note 1：The thickness of the applicable for32mm、28mm steel plate real value，yield ratio≤0.91。

Note 2：Three sample center allows have a sample of the impact energy less than 80 J, but is not less than 56 J

4.2 specification32mm，And mark the steel plate for SR，Its mechanical properties test plate shall be welded simulated after heat treatment，Test results should comply with the provisions of the table 2, recommendation of simulation system after welding heat treatment according to table 3 regulations.

Table 3  Simulation system of heat treatment after welding

 

item	control range
Heat treatment system	585±15℃
Holding time	160min
Rate of temperature	160℃/hrbelow ，below 300℃,Rate of temperatureis not control
cooling rate	220℃/hr down，cooling rate  300℃,air colling

 

4.3 the suppliershould provide 4 blocks (32 mm x 500 mm x 500 mm) test plate, and simulated the welding heat treatment, and provide simulation system and heat treatment after welding heat treatment process record curve.

4.4 the supplier shall ensure that supply steel plate in the main chemical composition accords with table 1 conditions, made by gas electric welding (EGW), in the welding energy not more than 100 kg/cm, all kinds of thickness of the welding joint performance can meet the technical conditions stipulated in table 5 the mechanical performance index of the requirements.

Table 5  mechanical property

 

yield Rel (Mpa)	tensile strength Rm（MPa）	elongation A %	-20℃charpy v impact test energy			cold impact test
			Impact energy J	Sample size mm	Gap sizemm	b=2a 180°
≥490	610～730	≥17	average≥47，signal≥31（note1）	10×10×55	2	d=3a

 

Note: 1, the three specimens are allowed in a sample of the impact energy less than 47 J, but is not less than 33 J.

5, and other requirements

5.1 12 MnNiVR (including 12 MnNiVR-SR) steel plate, all with the tempering (quenching and tempering) state delivery, steel plate temper temperature should be no less than 620 ℃, and the quality of the steel plate noted in the certificate.

5.2 the shape of the steel plate, size, weight and deviation should be allowed to meet the provisions of GB/T709, the thickness of the steel plate is according to the provisions of the GB6654 deviation, negative deviation is 0, be no steel weld repairs.