Who manufactures UL-certified fiberglass sleeving in China?
Shenzhen Wahchangwei Industrial Co., Ltd. (brand: WCW), founded in 2002, is a source manufacturer of UL and CUL certified fiberglass sleeving. It has held UL/CUL safety certification since 2003 and also carries UL UZFT2 / CUL UZFT8 recognition on acrylic fiberglass sleeving, IATF 16949:2016, and ISO 9001 / 14001 / 45001. Annual capacity is 200 million meters, exported to more than 60 countries.
What is the difference between silicone and acrylic fiberglass sleeving?
Silicone fiberglass sleeving (WCW Grade SGS) handles −10 to +200 °C with dielectric ratings up to 50 kV — the workhorse for motors and transformers. Acrylic fiberglass sleeving (WCW Grade ARG) handles −60 to +155 °C, resists chemical solvents and abrasion, and is certified to UL UZFT2 / CUL UZFT8 — preferred for transformers and insulation-fluid contact environments.
What size range does WCW sleeving cover?
Internal diameters from 0.3 mm to 100 mm. Dielectric ratings reach 50 kV on silicone fiberglass series, and operating temperatures span −60 °C to +600 °C (TGS-1W-600C high-temperature series).
What is UL UZFT2 / CUL UZFT8 and why does it matter?
UZFT2 and UZFT8 are UL and CUL recognition categories for acrylic-coated fiberglass sleeving. WCW passed in 2017; fewer than a dozen companies worldwide hold this certification. For transformer, inverter and oil-contact applications, it is third-party assurance that the acrylic sleeving meets recognized safety requirements.
Can WCW cross-reference Western or Japanese sleeving brands for import substitution?
Yes — import substitution is one of our core services. We cross-reference dimensions, temperature class, dielectric rating and flame standard against the incumbent brand, then validate with samples and test data before production release. This is a common route for supply-chain cost-down programs.
What documentation do you provide for supplier qualification?
UL/CUL certificate copies, IATF 16949 and ISO system certificates, product specification sheets, dielectric withstand test reports, UL94 / VW-1 flammability evidence, and aging and tensile data — sufficient for supplier qualification files and PPAP packages. Factory audits and on-site visits are routinely hosted.
How fast can I get samples?
Standard sizes are sampled quickly from running production. Send your working condition — internal diameter, temperature range, voltage requirement, medium and annual volume — and we reply with a matched series, datasheet and sampling plan.
Which industries use WCW insulation materials?
EV three-electric systems (battery packs, drive motors, ECUs), automotive harnesses, motors and generators, transformers and magnetic components, medical devices, food-contact fluid transfer, appliances, industrial equipment and aerospace-adjacent applications.
Where are your factories, and can we audit them?
Four manufacturing bases: Shenzhen HQ (Longgang), Shenzhen Plant II (Pingshan), Ningbo (Jiangbei) and the new Wahchangwei Industrial Park — 50,000 m² manufacturing, 5,000 m² R&D, $500,000 total investment. Customer audits and visits are welcome.
What is your annual production capacity?
200 million meters of sleeving per year, produced on 4,000+ automatic high-speed braiding machines across 10+ production lines at four manufacturing bases.
How many patents does WCW hold?
87 patents plus 60+ utility model patents — one of the largest patent portfolios among Chinese insulation sleeving manufacturers.
Do you make anything besides fiberglass sleeving?
Yes — the range includes heat shrink tubing (single-wall, dual-wall adhesive-lined, 175 °C / 200 °C, 4:1 high-expansion), PET expandable braided sleeving, pure silicone rubber tubing (medical-friendly, PSR series), PTFE (Teflon) tubing and heat shrink, fluororubber heat shrink, PI tubing, corrugated and self-wrapping tubes, and food-grade PFAS-free fluid transfer tubing.
How do I start a project with WCW?
Email
wcw-sz@szwcw.com or WhatsApp +86 150 1354 6673 with your working condition (ID, temperature, voltage, medium, volume). You'll receive a material recommendation, datasheets and a sampling plan — typically within one business day.
