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About SUS304-WPA,WPB

keyword
SUS304WPA
SUS304-WPB
SUS304-WPA
SUS304L

Question 素人君

There are materials named SUS304-WPA, WPB. Is the base material of this before the drawing process the ordinary SUS304? There are also 304-W1 and W2 materials, are these also made of SUS304? Does calling WPA, WPB, W1, W2 mean that SUS304, whose characteristics have changed due to the drawing process, are standardized separately? If so, SUS304 has various components such as SUS304L, M, H, etc., but do materials such as SUS304L-WPB, SUS304H-WPA also exist? And are they all standardized by JIS? I am very sorry to trouble you with so many basic questions, but it would be appreciated it if you could let me know. Thank you.
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Answer Tokai Spring

Thank you for your inquiry, Spring Newbie! !

① There are materials named SUS304-WPA, WPB. Is the base material of this before the drawing process the ordinary SUS304?
Answer: Yes, the base material is SUS304.

② There are also 304-W1 and W2 materials, are these also made of SUS304?
Answer: We haven’t used 304-W1 and W2 because they are not spring materials … (& gt; _ & lt;).

③ Does calling WPA, WPB, W1, W2 mean that SUS304, whose characteristics have changed due to the drawing process, are standardized separately?
Answer: SUS304-WPA and WPB are standardized by distinguishing SUS304 whose characteristics have changed due to the cold drawing process.

④ SUS304 has various components such as SUS304L, M, H, etc., but do materials such as SUS304L-WPB, SUS304H-WPA also exist? And are they all standardized by JIS?
Answer: Unfortunately they do not exist and are not standardized.

Once again, thank you for your inquiry.

Answer Anonymous

Please tell me the difference between SUS304-WPA and WPB.

Answer Tokai Spring

Dear Spring Newbie,
The difference between SUS304-WPA and SUS304-WPB is the difference in tensile strength. As for the material, after going through solid solution strengthening, the strength of the material is increased by wire drawing. To be more specific, WPA has a material strength smaller than WPB, and the value varies depending on the material diameter. (Refer to JIS G4314 for details.) WPB is commonly used to produce springs, while WPA is not widely distributed. In the case of SUS, the design allowable stress of spring is lower than that of piano wire, so if you want a high strength material, you will have to choose WPB. Besides, material manufacturers are likely to produce a lot of materials that are in high demand, so in my opinion, there is little WPA distribution. When we make a design proposal with SUS304 material, we often propose with SUS304-WPB, depending on the material diameter.
Once again, thank you for your inquiry!

Answer Eric Marfil

what is the difference of SUS304 WPB and SUS304 CSP?
are they the same?

Answer Tokai Spring

Dear Eric,

Thank you for your question!
SUS304-WPB is a stainless steel wire for springs specified in JIS G4314, one of the Japanese JIS standards.
SUS304-CSP is a stainless steel strip for springs specified in JIS G4313.

Both are for producing springs, however, the biggest difference is the shape of the material. SUS304-WPB is wire material and SUS304-CSP is plate or strip material.
The mechanical properties of them are also different. For more details, please check each JIS standard.

We hope it helps.

Best regards,
Tokai Spring’s Support Team

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