Stainless Steel CF8, CF8M, CF3, CF3M Butterfly Valve Material Introduction

Date: Nov 18, 2022 3,239 views Source: VALTEC China Valve Manufacture CO.,LTD

Stainless steel butterfly valve materials are mainly divided into 304, 316, 304L, 316L and other stainless steel materials. However, the material on the valve body does often appear CF8, CF8M, CF3, CF3M and so on.

There are many customers because it is written on the contract that it is a butterfly valve: DN50, 304, 20 sets. But when the goods arrived at the scene, it was found that there was no digital material such as 304 on the valve. Customers will have questions and ask why there is no 304 mark on the valve. The material element of 304 appears only in the “Valve Product Quality Certificate”. Here I will explain to you the difference between CF8 and 304.

CF8 is a standard material drafted by ASTM A351 for stainless steel casting materials (American Society for Testing and Materials). It is a standard name for material casting. 304 is also a name introduced by the United States, and the Japanese name for this is SUS304. 304 is forged or forged material. Such as steel pipes, steel plates, forgings, forgings.

CF8 and 304 are called 0Cr18Ni9 in China, and SUS304 in Japan. However, due to the continuous progress of the country, the standards of materials are constantly in line with international standards. As we see now. CF8, 304, 0Cr18Ni9 materials are almost close. Therefore, according to custom and easy to remember, whether it is casting, forging, forging, we call it 304. The mechanical properties and chemical composition are almost the same. But strictly speaking, the stainless steel valve should still be called CF8.

CF8, CF8M, CF3, CF3M are stainless steel castings in the American Standard ASTM A351 standard.

Stainless steel butterfly valve FAQ

ASTM A351 CF8 Stainless Steel?

ASTM A351 CF8 is the equivalent investment cast alloy of AISI 304 stainless steel, which belongs to austenitic stainless steel that presents good strength and ductility. As the chemical composition of CF8 includes approximately 18% chromium and 8% nickel by weight, it is also known as 18/8 stainless steel.

ASTM A351 CF8M Stainless Steel?

ASTM A351 CF8M is an upgraded austentic stainless steel alloy of CF8, which contains molybdenum element. The equivalent cast stainless steel alloy is AISI 316 stainless steel. Compared to CF8 stainless steel, The presence of molybdenum in CF8M increases the corrosion resistance and the resistance to pitting by chlorides.

What does CF8M Mean?

Introduction of Cf8m stainless steel, The number ‘8’ means the carbon content in the alloy and ‘M’ stands for Molybdenum.

What Does CF3M Mean?

C – The first letter means the service it is intedted to be used in corrosion resistant service. Meanwhile it may also means casting purpose because the F letter in F316 means forge process.
F – The second letter indicates the approximate location of the alloy on the iron-chromium-nickel (FeCrNi) ternary diagram.
3 – The only digits means the maximum allowed carton content in units of 0.01%. For example, CF3M has a maximum of 0.03% carbon content.
M – Molybdenum element contained in CF3M material.

What Does CF3 Mean?

C – The first letter means the service it is intedted to be used in corrosion resistant service. Meanwhile it may also means casting purpose because the F letter in F316 means forge process.
F – The second letter indicates the approximate location of the alloy on the iron-chromium-nickel (FeCrNi) ternary diagram.
3 – The only digits means the maximum allowed carton content in units of 0.01%. For example, CF3 has a maximum of 0.03% carbon content.
Note: Without M letter in CF3, this means there is no Molybdenum element contained in CF3 material.

Is CF8 as same as SS 304?

Stainless Steel SA-351 CF8 is the cast equivalent of Type 304 Stainless Steel. Part of a range of austenitic chromium-nickel alloys that provide good strength and ductility. They are also known as 18/8 stainless due to their chemical composition. It includes approximately 18% chromium and 8% nickel by weight.

Is CF8M as same as SS 316?

Stainless Steel SA-351 CF8M is a molybdenum bearing modification of CF8 Austenitic Steel alloy. It is the cast equivalent of wrought AISI 316 stainless steel. The presence of molybdenum increases the general corrosion resistance and the resistance to pitting by chlorides.

What is the difference between cf8m and SS316?

They are defined by different standards. Their chemistry and property are a little different too. CF8M is defined in ASMT A351, ASMT A743 and ASTM A744. It is for casting purposes only. SS316 is defined in ASTM A240 and ASTM A276. It’s for plate, sheet, strip or stainless steel bars.

What is the difference between CF8 stainless steel casting and CF8M?

CF8M stainless steel casting contains 2% to 3% molybdenum. CF8 stainless steel casting does not have. So CF8M cost is more.

Summary

CF8M is equivalent to China’s ZG0Cr17Ni12Mo2. Corresponds to 316 stainless steel.
CF8 is equivalent to China’s ZG0Cr18Ni9. Corresponds to 304 stainless steel.
CF3 is equivalent to 304L
CF3M is equivalent to 316L

Please feel free to contact VALTECCN butterfly valve suppliers and manufacturers for purchase requests or price inquiries regarding CF8(304), CF8M(316), CF3(304L), CF3M(316L) stainless steel butterfly valves!

Learn More: Stainless Steel Butterfly Valve