CRA Clad & Lined Steel Pipe

Note:
Base materials of the CRA clad or lined steel pipes include seamless or welded line pipes of API 5L Grade B, X42, X46, X52, X56, X60, X65, X70 and X80. In other circumstances, the base metal can also be provided as ASTM A106 Gr.B, ASTM A333 Gr.6, ASTM A335 Cr-Mo alloy steels (P5, P11, P22, P9, P91), etc.

The CRA cladding or lining material covers an extensive range of stainless steels and nonferrous alloys: SS 304/304L, SS 316/316L, SS 317/317L, Duplex 2205 (S31803), 2506 (S31804), 2507 (S32750), S32740, Alloy 254 SMO (S31254), 904L (N08904); Incoloy alloy 825 (N08825), Inconel alloy 625 (N06625), Hastelloy C-276 (N10276), Inconel alloy 59 (N06059), Alloy 31 (N08031), AL6NX (N08367), Alloy 20 (N08020), Monel alloy 400 (N04400); Titanium Grade 2, 5, 7, 9, 12; zirconium R60702; and some copper alloys.

Generally, CRA clad or lined pipes shall be manufactured as per API 5LD. The base material (steel pipe) conforms to API 5L, ASTM A106, ASTM A333, ASTM A335, etc. The cladding material shall conform to ASTM A240, A263, A264, A265, B898, B424, B443, B619, B622, B675, B265, B551.

Pipe diameter range: Ф50mm-Ф1800mm
Liner wall thickness: 0.5mm-3.5mm
Length: ≤15m

Manufacturing process of CRA Clad & Lined Steel Pipe
The CRA clad steel pipe is a bimetallic pipe composed of an internal (and in some cases external) CRA layer that is metallurgically bonded to the backing steel. The cladding may be bonded by hot rolling, coextrusion, weld overlay, explosion bonding, powder metallurgy, or some other process that produces a metallurgical bond. The CRA lined steel pipe consists of a carbon steel or alloy steel pipe with an internal or external CRA liner. The CRA liner is affixed or tightly fitted to the base-metal pipe full length by expansion, compression cold forming, or some other means. The CRA liner may be a tube or pipe inserted into a steel pipe, a plate or sheet rolled into a cylinder by expanding the liner and/ or shrinking the base pipe, or by some other applicable processes. The clad process results in a quite firm metallurgical bonding at the interface of the backing steel and the CRA layer. The mechanical bonding formed by the lining process is relatively “loose” in a lined pipe. Although the clad pipe exhibits better mechanical performance, its cost is relatively higher.

Pipe end treatment
Before clad pipe
The base pipe is rounded to ensure the quality of the on-site welding counterpart, and prevent the misalignment of the counterpart and root welding carburizing and ironizing

Clad pipe
Digital underwater deflagration composite technology, fully maintained hydraulic composite technology

After clad pipe
Pipe end surfacing + inner wall boring and milling to ensure welding progress