Introduction: Clear Communication Means Better Fasteners
Sourcing bolts, nuts, washers, or custom fasteners from Chinese manufacturers can be a cost-effective and efficient solution. However, miscommunication about technical specifications is one of the most common causes of production delays, quality issues, and failed inspections.
Language barriers, differences in standards, or vague RFQs (Requests for Quotation) can result in components that don’t meet your expectations—or worse, don’t function in your end product.
This guide offers practical advice for global importers on how to clearly and effectively communicate fastener specifications to Chinese suppliers.
1. Use International Standards to Define the Product
Start by specifying internationally recognized standards like:
- DIN / ISO for European buyers
- ASME / ANSI for North American buyers
- AS standards for Australia and New Zealand
Example:
Instead of saying “hex bolt,” say:
DIN 933, M12 x 80, Class 8.8, Zinc Plated, 100 pcs
This tells the supplier:
- The exact standard and dimension
- The material and strength class
- The surface coating
- The quantity
Vague descriptions like “M12 bolt, 80mm” leave room for interpretation and errors.
2. Include Drawings Whenever Possible
Technical drawings are the most effective way to reduce ambiguity. Even a simple 2D PDF with labeled dimensions can eliminate confusion.
Make sure the drawing includes:
- Thread type (e.g., M12 x 1.75 or 1/2″-13 UNC)
- Tolerances
- Material type (e.g., carbon steel, stainless 304/316)
- Coating or finish
- Heat treatment (if applicable)
If a 3D model is available (STEP, IGS, etc.), provide it alongside the 2D drawing. This helps factories with CNC programming or mold design.
3. Clarify Thread Type and Class of Fit
Many issues arise from thread mismatches between metric and imperial systems. Always specify:
- Metric or Imperial (UNC, UNF, BSW, etc.)
- Thread pitch (especially for fine or unusual threads)
- Class of fit (6g, 6H for metric; 2A/2B for imperial)
When in doubt, write it like this:
M10 x 1.25, right-hand thread, Class 6g
Or for imperial:
3/8”-16 UNC, Class 2A
Avoid using only local terminology or assuming the supplier will interpret your intent correctly.
4. Be Precise About Material and Mechanical Properties
Simply writing “steel” or “stainless” isn’t enough.
Instead, use:
- Carbon steel Grade 8.8 / 10.9
- Stainless steel A2-70 (304) or A4-80 (316)
- Brass C360 or aluminum 6061
If your application involves load-bearing, heat, or corrosion, material specification becomes critical.
Also state if certifications are required:
- Material Certificate (EN 10204 3.1)
- Tensile test reports
- Salt spray or hardness results
5. Explain the Surface Treatment Clearly
Surface treatment can affect corrosion resistance, tolerance, and compliance. Common types include:
- Zinc plating (white, yellow, black)
- Hot-dip galvanizing (HDG)
- Dacromet / Geomet
- Black oxide
- Passivation for stainless steel
Example specification:
Zinc plated, trivalent chromium, 8 μm minimum, ROHS compliant
Avoid generic terms like “coated” or “galvanized” without further detail, as they are interpreted differently in China.
6. Use Photos or Physical Samples to Reinforce Specs
Sometimes, a clear photo or an old sample says more than a thousand words. If you’re replicating a part, sending the sample to your supplier can greatly improve accuracy.
Tips:
- Mark critical dimensions on the photo
- Include a ruler or caliper in the image for scale
- Provide packaging photos if you have labeling or pallet requirements
Suppliers in China are very familiar with reverse engineering samples. Just be sure to still provide the technical specs so there’s no guesswork.
7. Translate Where Needed, But Keep It Simple
Most export-oriented Chinese suppliers understand English, but keep your language technical and direct.
Instead of saying:
“Can you make bolts kind of like these but a bit longer and stronger?”
Say:
“DIN 931, M10 x 100mm, Class 10.9, zinc plated, 1000 pcs, ROHS compliant.”
Avoid slang or idioms. Use bullet points and structured formats for your RFQs or emails.
8. Confirm All Specs in the PI (Proforma Invoice)
Before confirming your order, ensure that the Proforma Invoice (PI) includes:
- The exact fastener specification
- Drawing or part code reference
- Quantity per size and packaging method
- Delivery time and Incoterms
- Any required certifications
This document becomes your contractual reference in case of disputes, so it must reflect your technical requirements.
9. Build a Standardized RFQ Template
Create a reusable RFQ form for all your fastener orders. Include fields for:
- Part number
- Standard (DIN/ISO/ANSI)
- Material and grade
- Finish/coating
- Quantity per size
- Drawing reference or sample ID
- Certifications needed
Share this format with your supplier and request they use the same for future communication. It ensures consistency across orders.
Conclusion: Clarity Reduces Cost and Improves Quality
Communicating clearly and professionally with your Chinese fastener supplier isn’t just about avoiding mistakes—it’s about building long-term, efficient, and trust-based cooperation.
By providing standards, drawings, specific terminology, and structured documentation, you minimize the risk of misunderstandings and ensure the final product meets your expectations.
Need a fastener supplier that understands global standards and communicates clearly?
Contact Jiaxing Linkworld Fasteners today. Our team has over 20 years of experience working with technical drawings and complex international requirements. Submit a Quick Inquiry and get a detailed reply within 24 hours.