Manufacturing Process of Cement Mortar Lined Anti-Corrosion Steel Pipes

Cement mortar lined steel pipe is widely used in municipal water supply, sewage treatment and long-distance water transmission projects due to its excellent anti-corrosion performance and long service life. The cement mortar lining inside the pipe effectively isolates the steel substrate from direct contact with water, preventing electrochemical corrosion and biological erosion, and significantly extending the pipeline's service life.

The production process of cement mortar lined steel pipe includes several key steps, each of which directly affects the quality and durability of the finished product.

1.Steel Pipe Pretreatment

First, the steel pipe is inspected and cleaned to remove rust, welding slag, oil stains and debris from the inner wall. The inner surface is then blasted to achieve Sa2.5 cleanliness, creating a rough texture to ensure strong adhesion between the mortar and the steel pipe.

2.Cement Mortar Preparation

High-quality Portland cement and clean sand are mixed in a precise ratio (usually 1:2 to 1:3) with water and additives. The mixture is stirred to form a homogeneous, flowable mortar with good workability and strength.

3.Centrifugal Lining Process

The prepared mortar is injected into the steel pipe, which is then placed on a centrifugal machine and rotated at high speed. Centrifugal force evenly distributes the mortar against the inner wall, forming a dense, uniform lining layer with a consistent thickness of 6–12mm. The surface is then smoothed to reduce water flow resistance.

4.Curing and Drying

The lined steel pipe is cured under controlled temperature and humidity conditions for at least 7 days to allow the cement to fully hydrate and develop strength. After curing, the pipe is air-dried to prevent cracking caused by uneven moisture evaporation.

5.Quality Inspection and Finishing

Finished pipes undergo strict quality checks, including visual inspection, thickness testing, adhesion testing and port sealing. Only pipes that pass all inspections are marked, packaged and ready for delivery.

With a mature production process and strict quality control, cement mortar lined steel pipes provide a reliable, cost-effective solution for water transmission projects worldwide.