哈萨克斯坦采购需求：碳钢管、钢管、钢管、碳管、碳管、ERW钢管

I'm looking to source both round and rectangular steel pipes for an upcoming project. Please provide your specifications, including available sizes, material grades, and any relevant certifications. Additionally, I'd appreciate details on the minimum order quantities and your standard lead times for production and delivery. Furthermore, if you have any value-added services, such as custom cutting or finishing options, please include that information as well. Understanding the pricing structure for different order volumes would also be helpful. Looking forward to your prompt response so we can potentially move forward quickly.