1. Question: For the same size and grade, how does the cost of ERW compare to Seamless pipe?
Answer: Generally, ERW pipe is significantly more cost-effective than seamless pipe for the same specifications. The manufacturing process for seamless (like piercing a solid billet) is more energy and material-intensive. ERW starts with a flat sheet, which results in more uniform wall thickness and less waste, leading to a lower final product cost. For sizes above 6 inches, the cost advantage of ERW over seamless becomes even more pronounced.
2. Question: Is the weld in an ERW pipe considered a weak point compared to a seamless pipe?
Answer: With modern manufacturing technology, the answer is no. Decades ago, ERW seams were considered potential weak points. However, with today's high-frequency welding, post-weld heat treatment, and advanced 100% ultrasonic inspection, the weld seam is just as strong and ductile as the base metal. In fact, for many applications, the weld zone can be tougher than the base metal due to the refined grain structure. Destructive testing almost always shows the pipe failing in the parent metal, not the weld.
3. Question: What is the maximum pressure rating for your ERW pipes?
Answer: The pressure rating depends on three factors: the material grade (yield strength), the wall thickness, and the outer diameter. It is calculated using formulas from standards like ASME B31.3 (Process Piping) or B31.8 (Gas Transmission). For example, an API 5L X52 pipe with a specific wall thickness may have a working pressure of 1,500 PSI or more. We highly recommend you provide your design pressure and temperature, and our engineers can calculate the exact required wall thickness (Schedule) for your project.
4. Question: What is your policy on claims if the pipes arrive damaged or do not meet the specifications?
Answer: Customer satisfaction is our priority. We have a clear and fair claims policy. Upon arrival, you should inspect the goods immediately. If there is visible shipping damage, it must be noted on the Bill of Lading. For quality claims (e.g., failing to meet a test standard), we require that you contact us within 14 days of receipt. We will review the Mill Test Certificates, and if necessary, we can agree to send a representative or a third-party inspector to verify the claim. If the claim is valid, we will offer a replacement, a credit, or a negotiated settlement as per the Incoterms agreed upon.
5. Question: Do you provide any welding recommendations or technical support for using your pipes in the field?
Answer: Yes, we provide after-sales technical support. We can share our recommended Welding Procedure Specifications (WPS) for our various pipe grades to help you achieve sound field welds. Our technical team is available to answer questions via email or video call regarding fit-up, welding parameters, or post-weld heat treatment requirements to ensure your project's success.
