Home > About Us> Tech & Service

Steel pipe internal stratification

The tube is generally believed that non-metallic inclusions in the steel tube will destroy the continuity and compactness, severe inclusions will lead to appear the steel pipe delamination phenomena. Another thought is hydrogen induced cracking, namely due to hydrogen accumulation caused by metal steel internal gas pressure is too high, the formation of white spots in the round tube, crack extension occurs in the rolling process, and ultimately form a layered defects. In addition, the stress exceeds the strength of two rolls of plastic rotary piercing uneven deformation can also cause delamination.

the control measures of steel pipe internal stratification are:
1, Improved plastic toughness of tube billet
Improve the cleanliness of molten steel, reducing harmful inclusions; increase the proportion of the slab crystal axis, to reduce the center segregation and center porosity; using reasonable cooling system to avoid cracks appeared in the interior slab; billet or rolling slab to be taken offline slow cooling process, reducing internal stress, thus ensuring the microstructure and mechanical properties of steel billet and finished products meet the technical standards.
2, Reasonable control heating temperature
By measuring thermoplastic curve to choose the best heating temperature. Also note that there is enough heating tube holding time, to reduce the pipe plastic deformation resistance and improve toughness.
3, Reduce the roll speed
Speed ​​is a key parameter roll piercing process, in the roll speed from low to high variations in the process, there is a critical stratification began the roll speed. At lower roll speed, easy to form a tube cavity; higher roll speed, and capillary tube formation of layered defects easily. In order to eliminate delamination defects and capillary tube, roll speed should be reduced to the critical stratification began following the roll speed.

Welcome to Sunny Steel Enterprise Ltd.

Sunny Steel provide a wide range of steel products as Steel pipes, Seamless tube and seamless pipes, Alloy pipes, Pipe fittings, Composite steel pipe used in the industry, construction etc.

English Inglés SpanishEspañol
Recommended products
Pipe fittings
Pipe fittings are used to connect pipes.
Welded steel pipes Weld steel pipes
We produce an extensive selection of weld steel pipe
Welded steel pipes Anti corrosion pipe
Anti-corrosio pipe is processed through the preservation
Ceramic-Lined Pipes
from a single spool piece to complete piping systems.
Pipe flanges
Pipe flange are a method of connecting pipes, valves.
Pipe Fitting Accessories
We are passionate in Stub Ends, Bolt Sets, Fasteners
Sunny Steel Blog

About Sunny Steel

Our team are highly trained and experienced in servicing and producing all types of steel supplies. Whether you've got a large construction project, or need parts for industrial machinery, our team of steel fabrication consultants will ensure that your project is provided with the parts you need, when you need them.

Oline Customer Service : Chat with QQ Skype Me??

Contact us

Tech& Service