WELLELE FAQ — Frequently Asked Questions

Practical questions from engineers and procurement specifying custom insulation components.

What information do you need for a quote?

A dimensioned drawing plus application, material grade, operating temperature and voltage, tolerances, annual quantity and any test standard (for example IEC 60269). Without a drawing, send the closest sketch and we will list what is missing.

Do you make to drawing or only stock sizes?

Both. Stock sizes exist for common tubes and sheets, but custom parts are made to your drawing. The drawing is always the spec.

Which material should I choose for a fuse tube?

It depends on voltage, clearing energy and temperature. Vulcanized fiber is the LV default; ceramic epoxy glass or arc-quenching composites suit MV/HV. Send the duty and we specify the grade.

Can you meet IEC 60269 dimensions?

Yes. We manufacture to the dimensioned drawing you supply, including IEC 60269 body lengths and end-cap geometry.

What certifications do you hold?

ISO 9001:2015 quality system, with RoHS and REACH compliant materials available. Material flame class (UL 94 V-0) is grade dependent.

What are your typical lead times?

Lead time depends on material, process and tooling. Stock material ships in 1-2 weeks; made-to-drawing parts with new tooling start at 4-6 weeks after first-article approval. We confirm the exact date with the quotation.

Do you supply inspection documentation?

Yes. Incoming, in-process and final inspection with batch documentation can be supplied on request, per your quality plan.

What is the difference between heat-shrink and cold-shrink tubing?

Heat-shrink tubing requires a heat source (hot air gun or oven) and shrinks tightly over the joint. Cold-shrink tubing comes pre-stretched on a removable core; it relaxes over the joint when the core is pulled out. Heat-shrink handles wider temperature and chemical exposure; cold-shrink wins for confined spaces where heat is unsafe.

Do you ship internationally and how?

Yes. We export to North America, Europe, Southeast Asia and Australia. Standard shipping methods: air freight (DHL/FedEx) for urgent samples, sea freight (LCL/FCL) for volume. We provide commercial invoice, packing list and, where required, a certificate of origin (CO) or manufacturer test certificate (MTC).

Do you accept Letters of Credit?

Yes. We accept Irrevocable LCs at sight, documentary collections (D/P, D/A) and wire transfer. Payment terms are typically 30 percent deposit on order and 70 percent against clean bill of lading. Terms are confirmed during the RFQ reply.

What is your minimum order quantity?

Stock sizes: no MOQ — single pieces are accepted. Custom made-to-drawing parts: MOQ starts at 100 pieces for standard materials and 500 pieces when new tooling or prepreg runs are required. We can produce pilot quantities of 10-50 for material trials.

Do you provide samples?

Yes. Standard stock samples ship in 3-5 days at no cost for regular clients. Custom or made-to-drawing samples are quoted with material and tooling cost plus shipping. Sample lead time is typically 1-3 weeks.

How do I specify a heat-shrink busbar sleeve?

Provide the busbar cross-section (width x thickness), the shrink ratio you need (2:1, 3:1, 4:1), operating voltage class and peak temperature. We check recovery force and dielectric strength against your application and suggest wall thickness and material. A drawing or sketch is enough to start.

Can you cut, punch or machine to length?

Yes. Secondary operations — cutting, punching, drilling, threading, CNC turning — are available in our Suzhou factory. Specify lengths and tolerances on the RFQ; we include them in the quotation and first-article inspection plan.

Did not find your answer?

Send the drawing and we will review it with you.

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