Long‑distance transmission pipelines (spiral‑weld pipes and longitudinally submerged‑arc welded pipes) operate under the harshest service conditions on Earth (extreme cold, high pressure, and corrosion). Steel pipe materials are continuously upgraded to high‑strength steels (API 5L X60, X70 and even X80). The core pain point is: while guaranteeing the multi‑wire high‑speed welding efficiency of pipe mills, it is mandatory to strictly maintain deep‑cryogenic impact energy from ‑40°C to ‑60°C (e.g., above 27J or even 50J), and expensive alloying elements must never be burnt out.
Our pipeline‑grade sintered fluxes adopt high‑purity mineral raw materials with precisely controlled basicity. On one hand, high basicity ensures extremely low weld metal oxygen content, greatly improving impact toughness. On the other hand, its neutral metallurgical reaction never burns out key strengthening elements such as Molybdenum (Mo) and Nickel (Ni) in welding wires, securing stable yield strength for high‑grade pipeline steels.
In the tender for API 5L X70M PSL2 high‑strength pipeline steel for North Africa (e.g., national‑level projects in Algeria), we adopted special pipeline welding wires containing 0.52% molybdenum alloy combined with high‑purity pipeline‑grade sintered fluxes. Outstanding impact energy of 51J was stably achieved under extreme cold conditions of ‑50°C, fully exceeding the access thresholds of top‑tier international engineering projects.
X52 / X60 Grade Pipelines:
GJ‑101Q (fluorine‑basic type dedicated for pipelines) + EM12K / EM13K (For steel plates with scale, high‑silicon EM13K provides excellent porosity resistance).
X70 Grade High‑Strength Pipelines:
GJ‑101Q or GJ‑107 (aluminate‑basic type) + EA2 (S2Mo) or S3Ni1Mo alloy welding wires, ensuring ultimate safety margin.
Copyright © 2026 by Jinan Gujin Welding Materials Co,. Ltd. All Rights Reserved
