About Changzhou Joyruns Steel Tube Co., Ltd - Heat Exchangers Supplier in China

Based in China, Changzhou Joyruns Steel Tube Co., Ltd lists eight active products across several metal tubing categories. The catalogue covers heat exchanger tubes, CNC machine spare parts, steel coils, titanium, aluminium and stainless steel tubes, as well as double‑wall coated bundles. Products are classified under HS code families 7304, 7306, 7403, 7608, 8108 and related sections, reflecting carbon steel, alloy steel, copper, zinc and titanium materials. The supplier’s portfolio includes both standard pipe dimensions and specialised heat‑exchanger geometries. Export listings show a focus on raw tube forms rather than assembled fittings.

The precision tube entry specifies carbon steel grades E235, E255 or ST37 and is recorded under HS code 7306.36. Heat‑exchanger carbon tubes comply with ASTM A179 and A192 specifications, while the double‑wall zinc‑coated Bundy tube (4.76 × 0.6 mm) uses low‑carbon SPCC/SPCD steel under HS code 7306.30. Titanium tubes are offered in CP Ti Grade 1 and Grade 2 per ASTM B338 and fall under HS code 8108.90. Aluminium tubes of the 1000 series (1050, 1060, 1070) are listed with HS code 7608.10, and stainless steel tubes correspond to ASTM A312 grades 304/304L/316/316L under HS code 7304.11. A double‑wall copper‑coated Bundy tube is catalogued with HS code 7403.21, indicating a copper‑plated low‑carbon steel construction.

Product Range and Specialties of Changzhou Joyruns Steel Tube Co., Ltd

The catalogue presents carbon steel precision tubes, zinc‑coated and copper‑coated double‑wall Bundy tubes, titanium tubes, aluminium 1000‑series tubes, and austenitic stainless steel tubes. In the steel tube market, carbon steel grades such as E235/E255 (equivalent to EN 10025 S235JR) are common for structural and mechanical applications, while ASTM A179/A192 tubes are typical for high‑temperature heat exchangers. Titanium tubes supplied to ASTM B338 Grade 1 and 2 are standard for aerospace and chemical processing due to corrosion resistance. Aluminium 1050‑1070 grades are widely used where high conductivity and low strength are acceptable, and stainless steel 304/316 grades meet the 1.4301/1.4401 specifications for corrosion‑resistant piping. Buyers often request material certificates, dimensional tolerances (±0.05 mm), wall‑thickness tolerances, and surface finish grades such as mill finish or polished.

Trade and Export Information - Changzhou Joyruns Steel Tube Co., Ltd

China is a leading exporter of metal tubes, with the majority of shipments directed to automotive, HVAC, oil‑&‑gas and renewable‑energy sectors in Europe, North America and Southeast Asia. HS codes 7304 - 7306 cover carbon and alloy steel tubes, 7403 addresses copper‑plated steel, 7608 includes aluminium tubing, and 8108 pertains to titanium products; customs inspections routinely verify material declarations and compliance with CIQ regulations. Typical certifications requested by importers include ISO 9001 quality management, mill test reports (MTR) and, where applicable, ASTM or EN conformity certificates. Standard packaging involves wooden crates or bulk drums with moisture‑resistant liners, sized for 20‑ft or 40‑ft containers, and Incoterms such as FOB Changzhou or CIF destination are commonly negotiated. Export documentation from China also requires a commercial invoice, packing list, certificate of origin and, for certain grades, a hazardous‑material declaration.

Sourcing from Changzhou Joyruns Steel Tube Co., Ltd - Buyer Guidance

Prospective buyers should request the latest mill test report for each tube grade to confirm chemical composition and mechanical properties such as tensile strength and elongation. For heat‑exchanger tubes, obtaining an ASTM compliance certificate and a dimensional inspection report (outside diameter, wall thickness, straightness) is standard practice. Samples of the double‑wall coated bundles should be examined for coating adhesion and thickness, typically measured in microns. Verification of the correct HS code and material description on the commercial invoice helps avoid customs delays. Prior to placing a bulk order, confirming packaging details, container loading plan and lead time - often 30‑45 days for stainless and titanium tubes - is advisable.

What material grades are available for the precision carbon steel tube?

The precision tube is offered in carbon steel grades E235, E255 or ST37, which correspond to EN 10025 S235JR specifications and are listed under HS code 7306.36.

Which standards apply to the heat‑exchanger carbon tubes?

Heat‑exchanger carbon tubes are produced to ASTM A179 and A192 requirements, covering dimensions, wall‑thickness tolerance and high‑temperature performance.

What are the dimensions and coating of the double‑wall Bundy tubes?

Both the zinc‑coated and copper‑coated Bundy tubes have an outer diameter of 4.76 mm and wall thickness of 0.6 mm; the zinc version uses SPCC/SPCD low‑carbon steel (HS 7306.30) and the copper‑coated version uses a copper plating on low‑carbon steel (HS 7403.21).

Which titanium grades are supplied and under what HS code?

Titanium tubes are supplied in commercially pure Grade 1 and Grade 2 per ASTM B338 and are classified under HS code 8108.90.

What aluminium alloy series are offered and what is the typical HS code?

The aluminium tubes are from the 1000 series - grades 1050, 1060 and 1070 - and are recorded under HS code 7608.10.

What stainless steel grades are available for the ASTM A312 tube?

Stainless steel tubes conform to ASTM A312 and include grades 304, 304L, 316 and 316L, with the HS code 7304.11 indicating austenitic stainless steel pipe.

What documentation should a buyer request before ordering?

Buyers should ask for the mill test report, relevant ASTM or EN certification, coating thickness verification (for coated bundles), and a full commercial invoice that lists the correct HS code and material description.