What Are Our Concerns About Bearings（59）

Q1：How does forging (monitored by both forging temperature and post forging cooling) affect the post forging hardness of forgings?  

A:The forging temperature must be controlled within the standard forging range, the faster the cooling speed, the higher the hardness, the greater the brittleness, generally slow cooling, and then heat treatment to obtain the required hardness.

Q2:What is ASTM A105 GR.2 standard material?

A:It is a carbon steel forgings material for pipe components in ASTM standard, the standard number is ASTM A105, but Gr.2 is incorrectly written and should be marked as 300LB or 3000LB, not Gr.2.  

Q3:20R steel plate and billet production standard No.  What is the manufacturing standard number of 20# billet?  

A:The standard for 20R is GB 6654-1996 steel plate for pressure vessels  

20# steel has a number of standards: non forgings: GBT 699-1999 high quality carbon structural steel  

Forgings: CARBON steel and low alloy steel forgings for JB 4726-2000 pressure vessels.

Q4:Do profiles need to be normalized?  If you want to be in rough processing can also be tempered ah? Forgings: normalizing, roughing, tempering?  

A:Profiles can be normalized, but general profiles are not heat treated.  It depends on the nature of the material.  If the heat treatment is carried out, it is generally handled when it comes out of the steel mill.  

Forgings, want to see what material, what standard is used, can carry out the corresponding heat treatment.  

Quenching and tempering is a kind of heat treatment.  Heat treatment of materials shall be carried out according to corresponding standards and design requirements.  Rather than heat treatment in general.  

Q5:What is marine ring forgings DNV detection standard？

A:DNV is the Norwegian Classification Society, they just authenticate your test, they can’t test themselves, the test is based on custom standards.

Q6:In the valve, what material is F52, what characteristics is it? Is it casting or forging? What material should the valve stem be?  

A:Duplex stainless steel, forging grade.  The material selection of stainless steel valve stem is usually not less than the body material, encounter such special material, in the case of strength to meet the requirements, generally choose the same material with the body.  

Q7: How to do stainless steel 1Cr18Ni9 forgings flaw detection grain coarse?

A:Grain size is a characteristic of forgings themselves, so many flaw detection standards have application restrictions, which cannot be changed.

However, if quality control is needed, you can optimize from the selection of detection surface (such as single-side detection to double-side detection), detection frequency (using a probe of less than 0.5mhz), large probe diameter, changing the coupling status, etc., and the evaluation method should try to choose the bottom wave (if any) attenuation and other methods.

The penetration test can also be used for evaluation.

Q8:How to detect the remanence of large forging gear? How do I get rid of it?

A:General remanence size is more customer and standard requirements.  Gears are generally 3~5GS.  Demagnetization generally in large magnetic particle inspection machine with demagnetization device, demagnetization magnetic particle inspection machine is generally used to detect the attenuation method.  Of course, there are far from the method, and so on, according to the size, shape and weight of the workpiece.  

Q9:What electrode with Q245R+16Mn ⅱ forgings welding?

A:Q245R belongs to carbon structural steel, 16Mn ⅱ is the new standard Q345 belongs to alloy structural steel, welding electrode according to 16Mn ⅱ selection.  

J502(E5003) electrode for WELDING Q245R+16Mn ⅱ forgings  

Q10:What material is industrial valve,A582*M34? What’s the price?

A：A pressure of 800 pounds should equal 14mpa.  

Body material A105 is ASTM standard number, A stands for common carbon structural steel.  Standard name: Carbon steel forgings for pipe parts.  Because this standard only provides a carbon steel forgings, A105 also counts as a forged carbon steel brand.  A105 is also a material code, belongs to special steel, is a cold forged steel.  A105 is a low carbon steel forgings, similar to 20 steel.

Q11:What are the mechanical properties of A105?

A:A105 is the American ASTM standard number, and A stands for ordinary carbon structural steel.  Standard name: Carbon steel forgings for pipe parts.  Because this standard only provides a carbon steel forgings, A105 also counts as a forged carbon steel brand.  A105 is also a material code, belongs to special steel, is a cold forged steel.  A105 is a low carbon steel forgings, similar to 20 steel.  Its standard has two, one is the American standard “ASTM A105/A105M pipe components for carbon steel forgings”, the second is the Chinese standard “GB/T12228-2006 general valve carbon steel forgings technical conditions”.  

 Composition C:≤ 0.35Si :≤ 0.35Mn: 0.6-1.05s :≤ 0.050P :≤0.040, mechanical properties between 20 forged steel and 16Mn forged steel. 

 Note: In the pipeline system, A105 can replace No. 20 in general, but No. 20 cannot completely replace A105, because the strength difference is still large.  However, A105 is less resistant to SCC than No.20.  

Q12:Dingxi 15MnV round steel; How much is 15MnV forgings a ton?

A:15MnV round steel price;  15MnV steel plate manufacturer 15MnV round steel mechanical properties;  15MnV steel plate chemical composition – 1392013711815MnV round steel specifications;  15MnV steel standard 15MnV round steel weight algorithm;  15MnV steel plate cutting and selling  

Q13:Why must large forgings be free forged?

A:The main reason is that the largest forging hammer in China is only 16 tons, and the equipment standard for large forgings is too low.  

General large die forgings in China mainly rely on imports, mias in Russia has a too 50 tons of air hammer, can forge 5 meters long Marine crankshaft, but because of his equipment is relatively old, forging accuracy is not high!

There is also a method of splint hammer forging, which can be more accurate, so the general large forgings use free forging  

Q14:There is a 400X700 carbon steel forgings, which requires 1.6 holes for ultrasonic flaw detection, so what type of probe should be used?  

A:If you use the test block method, you have to use the standard test block to do, if you use φ 1 flat bottom hole to do, even if the workpiece detection with scanning sensitivity, can be detected, with φ 20,2.5 frequency of flaw detection, butt weld see you use what standard to detect, there are φ 1\ φ 2\ φ 3 test block, DAC curve, in detection,35 hope to use two probes K2\K  1. Double-sided and bilateral scanning was performed  

Q15:What is the inspection content and method of alloy steel forgings for ASME SA-336/SA-336M high temperature pressure parts?  

A:General detection of steel forgings, first material appearance detection, 1: no cracks;  2: clear label (material standard + manufacturer’s label + size);  In the certificate testing, material element analysis, hardness, mechanical properties, V-port impact value, X-ray, heat treatment, material standard (year number, etc.) and so on.