The "water ripple" defect appears on the surface of the medium and thick 304 stainless steel plate. How to control it?
In the production of 304 stainless steel plates, due to incomplete descaling of the 304 stainless steel plates, the oxide scale is pressed into the steel plates during rolling and straightening. After being removed by shot blasting, the appearance of Thickness 0.3-120mm 304l hairline finish stainless steel sheet will appear as Regular flake or irregular strip defects are called "water ripples". Studies have shown that the main reasons for the occurrence of "water ripple" defects are incomplete removal of oxide scale from 304 stainless steel plates, poor overlapping of high-pressure water nozzles, low roller hardness, and excessive pressure on the pre-straightener. The relevant control methods are:


1. Thickness 0.3-120mm 304l hairline finish stainless steel sheet reduces slab heating temperature

The method of lowering the heating temperature reduces the temperature of the steel coming out of the heating furnace from the previous 1190 ℃ to 1160 ℃. This method reduces the probability of the "water ripple" defect of the 304 stainless steel plate to a certain extent. The severity of the water ripple defect is dropped.


2. Thickness 0.3-120mm 304l hairline finish stainless steel sheet optimized phosphorus removal process

In order to compensate for the occurrence of band-shaped "water ripples" in 304 stainless steel strips caused by poor overlapping of high-pressure water nozzles, the pre-machine descaling system is used to descale the steel plates rolled from the back of the machine to the front of the machine. To a certain extent Reduces the occurrence of band-like "water ripples". At the same time, the descaling system was modified and a post-machine descaling system was added to further eliminate the occurrence of band-like "water ripple" defects in 304 stainless steel strips.


3. Thickness 0.3-120mm 304l hairline finish stainless steel sheet uses high hardness rollers

High-chromium iron rolls are used. The roll surface hardness is about 75 HL on the Leeb hardness scale, which is 10 HL higher than the original high-nickel-chromium rolls. Observe the conditions after use of the rolls. After dismounting, the roll surface is smooth. Thickness 0.3-120mm 304l hairline finish The stainless steel sheet is covered with a fine oxide film. The surface of the rolled steel sheet is smooth and clean, and the occurrence rate of "water ripple" defects is greatly reduced.