Reduction of Nb Steel Surface Cracks and Prevention Measures

Date: 2023-07-24

Reduction of Nb Steel Surface Cracks and Prevention Measures Transverse cracks will affect the finished product rate just after rolling. Increase billet cleanup time, both great harm. The slab temperature is brittle zone of 700-900 ℃. The reason the lower surface cracks is 1050-1100 ℃, transverse cracks on the surface of the reason is the billet surface by a large segment straightening straightening stress. Niobium nitride in the austenite grain boundaries reduces the binding force, the grain boundary precipitation. At this point in the curved section slab junction arc poor, resulting in a lower surface cracks. Vertical cracks and chemical composition, mold cooling water temperature, mold equipment, the chemical composition of the slag, continuous casting machine precision secondary cooling system related. Related prevention measures: 1. Control steel composition. Try to prevent wC is 0.12% -0.16% D36 steel carbon content in the smelting process control method according to the upper limit. Can effectively reduce the cracks. Peritectic reaction zone. 2. Control crystallization temperature constant mold temperature, mold temperature changes effective way to improve is to increase the mold cooling water preheating device. Suppressing the occurrence of cracks when the weather changes. Can also be used after every stop pouring and pouring time is not open when the water temperature is below 20 ℃ mold mold cooling water, to ensure that the temperature of the casting mold fashion. 3. Adjust the crystallization process parameters to adjust the amount of water the size of the mold, according to different copper thickness. By adjusting the amount of water to ensure that the different stages of the same mold cooling intensity. 4. To improve the secondary cooling system, improving the straightening zone temperature, by optimizing the secondary cooling system. Prevent brittle zone billet straightening, can better reduce the likelihood of slab transverse cracks. 5. Strand by strand appearance cleanup and removal of the slab scarfing corner, is an effective means to clean up the slab billet final quality assurance. We can improve the final quality of the slab. Post time: Jul-24-2023

Prev : Precision Tube length Measurement Method
Next : Deformation Strengthening of High-pressure Alloy Pipe
Tags : efw pipe , galvanized steel water pipes , octg casing , oil pipe

News

Latest news list

How to Choose Stainless Seamless Steel Pipe for High-Temperature Applications

High-temperature piping requires more than simply selecting a stainless steel grade,As temperature increases,material strength,corrosion behavior,thermal expansion,pressure resistance,and long-term stability become increasingly important,For this reason,stainless seamless steel pipe should be selected against the complete service condition rather than temperature alone,
How Stainless Seamless Steel Pipe Is Manufactured: From Billet to Finished Pipe

Stainless seamless steel pipe is used in chemical processing,oil and gas,power generation,water treatment,food processing,and other applications where material performance and pressure integrity matter,But a finished pipe does not become reliable simply because it is made from stainless steel,Its quality is built through material control,forming,heat treatment,dimensional control,inspection,and traceability,Understanding how stainless seamless steel pipe is manufactured gives engineers and technical buyers a better way to evaluate suppliers beyond price,surface appearance,or a product catalogue,
LSAW Steel Pipe Maintenance: Extend Pipeline Service Life

Installing a properly specified LSAW steel pipe does not eliminate the need for pipeline maintenance,Once a pipeline enters service,corrosion,coating deterioration,mechanical loading,ground movement,operating changes,and environmental exposure can gradually affect its condition,For large-diameter pipelines,a practical maintenance program should focus on identifying changes early and taking corrective action before a manageable condition develops into an integrity problem,The objective is not simply to inspect the pipe,It is to understand the condition of the complete pipeline system and respond based on evidence,
How LSAW Steel Pipe Performs in High-Pressure Pipeline Systems

High-pressure pipeline systems place demanding requirements on pipe material,dimensions,weld integrity,inspection,and operating conditions,For large-diameter pipelines,LSAW steel pipe can be an effective solution because its manufacturing process allows large outside diameters and substantial wall thicknesses to be produced from steel plate,However,selecting LSAW steel pipe for pressure service is not simply a matter of choosing a thicker wall,The pipe specification needs to match the actual design pressure,temperature,fluid,diameter,applicable code,and service environment,
How to Prevent LSAW Steel Pipe Corrosion in Water and Buried Pipeline Systems

LSAW steel pipe is widely used for large-diameter water transmission,buried pipelines,and other infrastructure projects where strength,dimensional control,and long-term service reliability are important,However,pipe strength alone does not prevent corrosion,For buried or water pipeline systems,corrosion protection should be considered from material selection and coating through transportation,field welding,installation,and long-term inspection,A coating system should also be selected according to the actual operating environment rather than simply by initial cost,