1. **Difference between 105C and 106C:**
- **105C** and **106C** are likely shorthand references to ASTM A105 (carbon steel forgings) and ASTM A106 (seamless carbon steel pipe for high-temperature service). The "C" in A106C refers to Grade C, which has higher tensile strength than Grades A and B.
2. **Difference between ASTM 105 and ASTM 106:**
- **ASTM A105** is a specification for carbon steel forgings used in piping components (flanges, fittings, valves).
- **ASTM A106** covers seamless carbon steel pipes designed for high-temperature service (e.g., boilers, refineries).
3. **Difference between ASTM A106 and SA106:**
- **ASTM A106** and **SA106** are technically the same; "SA" denotes inclusion in the ASME Boiler and Pressure Vessel Code (BPVC). SA106 is the ASME-adopted version of ASTM A106, with identical requirements unless modified by ASME.
4. **What is SA210 material?**
- **SA210** is an ASME standard for seamless medium-carbon steel pipes used in boilers and superheaters. Common grades include A210A-1 (similar to AISI C-Mn steel) and A210C (higher strength).
5. **ASTM standard for Schedule 40 steel pipe:**
- Schedule 40 pipes can be made to multiple ASTM standards, but common ones include:
- **ASTM A53** (welded/seamless, general use)
- **ASTM A106** (seamless, high-temperature)
- **ASTM A312** (stainless steel, for corrosion resistance)
- The "Schedule 40" dimension standard is governed by **ASME B36.10M** (carbon/alloy steel) or **B36.19M** (stainless steel).
