FAQ - Frequently Asked Questions | Carbonpipe
Frequently Asked Questions
Common questions from carbon fiber buyers — answered by our factory team.
1. Are you a factory or a trading company?
We are a factory. WHYUCHUANG Carbon Fiber Technology Co., Ltd. is located in Huancui District, Weihai City, Shandong Province, China. We manufacture roll-wrapped and pultruded carbon fiber tubes, rods, sheets, strips, and square tubes in-house since 2013. You buy directly at factory prices.
2. What is the minimum order quantity?
For standard in-stock products, the minimum order is 1 piece. For custom sizes and specifications, the minimum order quantity depends on the specific dimensions — small-diameter tubes (under 10mm) can be ordered in lower quantities, while larger or non-standard sizes may require a higher minimum. Contact us with your dimensions for a quote.
3. How long does delivery take?
In-stock products ship within 24-48 hours. Custom orders typically take 5-15 business days depending on complexity. International delivery via DHL, FedEx, UPS, or air/sea freight takes 5-12 business days to most countries.
4. How do you handle quality control?
Every batch is tested for tensile strength, dimensional accuracy (within ±0.1mm), wall uniformity, surface finish, and straightness before shipping. We reject anything that does not meet specification.
5. Can you cut tubes to custom lengths?
Yes. We cut to your exact specifications at no extra cost. Just specify the length in your order or in the custom order form.
6. What payment methods do you accept?
We accept PayPal for orders. For larger B2B orders, bank transfer (T/T) is also available. Contact us for details.
7. What is your return policy?
If a product is defective or not as described, contact us within 14 days of delivery for a replacement or refund. See our Refund Policy page for details.
8. Do you offer technical support?
Yes. Our engineering team can help you select the right tube, rod, or sheet for your project. Email us at wh59ok@gmail.com or call 86 0631 5128666 (Mon-Fri, 9:00-18:00 GMT+8).
9. Can you produce custom carbon fiber parts?
Yes. We offer custom manufacturing for non-standard sizes, special weaves, and specific applications. Use our custom order form to submit your requirements, and we will reply within 24 hours.
10. Is carbon fiber safe to work with at home?
Carbon fiber itself is safe, but the dust from cutting and sanding is conductive and can irritate skin and lungs. Always wear a respirator (N95 or better), gloves, and long sleeves. Vacuum the dust instead of blowing it around.
11. What tolerances can you hold on tube diameters?
Our standard tolerance is ±0.1mm on outer diameter for roll-wrapped tubes and ±0.05mm for pultruded products. Wall thickness is held within ±0.1mm. For critical aerospace or medical applications, tighter tolerances are available on request — just let us know your requirement in the custom order form.
12. Can I get a sample before placing a bulk order?
Yes. We regularly send samples to customers before bulk orders. For standard in-stock sizes, you can simply order 1 piece from the website — there is no minimum. For custom samples, we charge a small sample fee that is fully refundable when you place a production order.
13. Do you offer quantity discounts?
Yes. Pricing is tiered — the more you order, the lower the unit price. As a factory, we can offer better rates than traders because there is no middleman. Contact us with your target quantity and we will send a volume quote, usually within the same business day.
14. How are your products packaged for shipping?
Tubes are individually wrapped in protective film, bundled with foam padding at the ends, and packed in reinforced cartons or wooden crates for larger diameters. We use rigid packaging to prevent bending and surface scratches during international transit. Breakage in transit is extremely rare, and if it happens we replace it free of charge.
15. What resin system do you use?
We primarily use high-grade epoxy resin systems. Standard products use 3K twill weave prepreg with epoxy for roll-wrapped tubes, and epoxy resin with T300-grade carbon fiber for pultruded products. Epoxy gives the best balance of strength, toughness, and UV resistance. If you need specific certifications (e.g. flame retardant, marine-grade), contact us and we will match the right system to your application.
16. Can you produce custom colors or surface finishes?
We offer matte, glossy, and plain-weave surface finishes as standard. Custom colors are possible for some product lines using colored resin or surface films. For most structural applications we recommend keeping the natural carbon finish — it has the best UV stability. If you need a specific look, send us a photo of what you want to achieve.
17. How do I measure and select the right tube size?
Measure the outer diameter (OD) with a caliper at the tube end. For a bearing fit, measure the bearing's inner bore and choose a tube OD slightly smaller. For push-fit joints, choose the tube OD that matches the mating part. If you are replacing an existing part, measure both the OD and the wall thickness. When in doubt, contact us — our engineers help customers select the right size every day, and we will reply within 24 hours.
18. Do you ship worldwide? Who pays customs and duties?
Yes, we ship worldwide via DHL, FedEx, UPS, and air or sea freight. Duties and import taxes vary by country and are quoted separately based on the destination country's rate — we will clarify all costs before you pay, so there are never surprise charges.