About Q345R Detailed introduction

What is the Q345R steelplate？

 Q345R steel plate grade representation method notes:                       

   The English letter "Q" represents the yield strength of the material, the number "345" indicates the value of the yield strength, and the English letter "R" represents the pressure vessel. Letter Q and R are the first letter of Chinese phonetic alphabet.                                                 

   Chinese reading Q345 Rong.                                                 

   Vessel Pressure translated into Chinese as: 压力容器(ya li rong qi),  Vessel(压力，ya li） Pressure （容器,rong qi）   

1.According to the steel rolling process(AS ROLLED)

Hot rolled 

General thickness range  ：4mm~40mm

General width range： 1500mm~4000mm

Normalizing heat treatment

General thickness range  ：40mm~80mm

General width range： 1500mm~4000mm

2.Impact test temperature 

Sample size: A=10*10*55; B=10*7.5*55; C=10*5.0*55; （measuring unit: mm）

Temperature：usually to 0℃

3.Flaw detection standard (Ultrasonic testing standards)

Current standard：NB / T 47013.3—2015

Previous standards:     JB / T 4730.3-2005 、GB / T2970-2004  

Ultrasonic testing level：Ⅰ 、Ⅱ、Ⅲ

4. Size, shape, weight, allowable deviation

4-1、The thickness of the steel plate license deviation shall comply with GB/T 709-2006,of B type deviation.

4-2、According to the requirements of customers can supply in accordance with GB/T 709-2006, of C deviation of steel sheet.

                                                           Table 5

5. Chemical composition：

                                      Table 1

5-1、

(a)    After the supply and demand both sides agreement, and indicate in the contract, 

the lower limit of C content range can not make the request. 

  (b)    In the case of not specified can not make the request.  

5-2、Thickness greater than 60 mm, C content can be up to 0.22%.

5-3、Q345R plates can be added in the niobium(Nb), vanadium(V), titanium(Ti), its content should be fill in in the certificate of quality, the amount of the above three elements content is not more than 0.12%.

5-4、As residual element chromium(Cr), nickel(Ni), copper(Cu) content should not greater than 0.3%, molybdenum content should be not greater than 0.08%, the total content of these elements should be not greater than 0.7%. If the supplier can guarantee can be analyzed.

6. Mechanical properties and process performance：

                                                             Table 2

6-1、Plate tensile test, charpy v-notch impact test and bending test results should comply with the provisions of the table 2.

6-2、Greater than 60 mm thickness steel plate, the supply and demand both sides agreement, and indicate in the contract, can not do the bending test.

6-3、According to the requirements of the demand side, the Q345R steel plate can be - 20 ℃ impact test, instead of in the table 2 0 ℃ impact test, the impact absorbing energy values should comply with the provisions of the table 2.

6-4、Charpy (v-notch) impact absorbing energy, calculated at three style of arithmetic mean, allowing one style of a single value is lower than the amounts given in table 2, but shall not be less than 70% of the specified value.

6-5、For thickness < 12 mm steel plate, charpy v-notch impact test should use auxiliary style, > 8 mm ~ < 12 mm steel plate auxiliary style size 10mm* 7.5mm*55mm , the test results shall be no less than 75% of specified value in table 2; 6 ~ 8 mm steel plate between the auxiliary pattern size to 10 mm * 5mm*55 mm, , the test results shall be not less than 50%, Less than 6 mm thickness steel plate does not need the impact test.

6-6、According to the requirements of the buyer, for more than 20 mm thickness steel plate can be high temperature tensile test, the test temperature should be indicated in the contract. The provisions of the high temperature plastic elongation strength RP0.2 or lower yield strength REL values comply with the provisions of the table 3.

 6-7、Table of high temperature mechanical properties 

                                                            Table 3

7. Manufacturing technology standard：

Current standard：GB 713-2014

Previous standards:     GB 713-2008 

8.Weight calculation method of the Q345R steel plate：

Length  values * width values * thickness values (need plus the added value of the thickness of the thickness of numerical） * density（7.85）

Boiler and pressure vessel steel plate thickness added value table

                                                              Table 4

If you measure the actual thickness as a result, containing less than the thickness of the thickness of the added value of (table 4), please follow the standards of GB/T 709-2006 (table 5) negative deviation standard range.

Important  Note: thickness of 10 mm, width is 2000 mm steel plate. Although theoretical calculation of the thickness of 10.35, as long as your measurement result is greater than or equal to 9.7 mm, also as a negative deviation in permission scope.

Don't have concerns, it is not what we in the fraud.

Typically, Q345R 10 mm thickness steel plate, measuring thickness can reach more than 10 mm, but can't rule out there sometimes will be less than 10 mm.

For example: the size of 20mm * 2000mm * 10000mm , the weight calculation is: (20+0.45) *2*10*7.85=3211【Unit:Kg】

Note: Under the condition of different thickness and width, the thickness added value is different.

9. Inspection certificate template：

Please click on this URL   http://www.ceheco.com/html/zhibaoshu/351