EN10139 DC04 7.94MM*0.9MM Double-wall zinc-coated Seamless steel tubing in coil

We supply steel tubes of many sizes with fine accuracies, made from low carbon steel strips.

Zinc galvanized double-wall steel tube has better corrosion protection than non-galvanized double-wall steel tube which is copper brazed

Bundy tube, sometimes called Bundy pipe, is the type of double-walled low-carbon steel tube manufactured by rolling a copper-coated steel strip through 720 degrees and resistance brazing the overlapped seam in a process called Bundywelding.

We offer single wall electro-welded steel tube, also known as single wall Bundy tube. Mostly it's coated with copper for automotive use. Also, it can be plated with zinc for automotive and condenser use, or coated with PVF for automotive use, as an economic alternative for double-wall welded steel tube.

Chemical Composition

Mechanical Properties

SINGLE WALL STEEL TUBING OD & WT TOLERANCE

All the tube diameters can be available plain, zinc-coated or copper coated.

PLAIN TUBE

Plain tube is supplied with its outside surface slightly oiled to improve the resistance to oxidation. Tube shall be kept in dry storages, away from air drafts, humidity or any other corrosive agents

ELECTROLYTIC BOTH SIDE COPPER COATING

The steel strip from which the tube is made shall be copper coated on both sides with a copper layer ≥2µm. The area along the welding seam, on the outside surface is not coated because of the scarfing operation to remove the excessive bead.

HOT DIP ZINC COATING

Tube outside surface can be coated with a layer of zinc whose weight is ≥ 70 grams per square meter determined by UNI EN ISO 1460/97. This coating the tube withstands to > 72 h in salt spray fog test before showing red rust (according to UNI ISO 9227).

WORKING SHOP

Laboratory Testing Equipment

PACKING