Coating standard: container steel surface treatment and inspection JH / T e02-2008

Core tips: 1 Scope This standard specifies the process, requirements, inspection standards and methods of steel surface treatment of general steel container steel 2 Normative references The terms in the following documents become the terms of this standard by reference to this standard For dated references, subsequent amendments (excluding Corrigendum) or revisions are not applicable to this standard However, parties to agreements based on this standard are encouraged to study the availability of the latest versions of these documents All without date Which is the price of Dajin diatom mud Recommended brief introduction: which is the price of Dajin diatom mud? How to buy genuine diatom mud? Guangdong diatom mud agent suggests placing a basin of cold water in the air conditioning room, so that the diatom mud wall can breathe effectively The feature of the breathing wall is obvious When the indoor air is dry, the diatom mud wall will release the absorbed water quickly Put it out to help regulate the indoor dry humidity It is suggested to place a basin of cold water in the air conditioning room, so that the wall of diatom mud can breathe effectively The feature of the wall that can breathe is obvious When the indoor air is relatively dry, the wall of diatom mud will absorb the water Coating home news: 1 Scope this standard specifies the process, requirements, inspection standards and methods of steel surface treatment of general container steel 2 Normative references the clauses in the following documents become the clauses of this standard through the reference of this standard For dated references, subsequent amendments (excluding Corrigendum) or revisions are not applicable to this standard However, parties to agreements based on this standard are encouraged to study the availability of the latest versions of these documents For undated references, the latest edition is applicable to this standard IS0 8501-1 preparation of steel substrates before application of paints - Visual assessment of surface cleanliness - Part 1: rust grades and rust removal grades of uncoated steel substrates and steel substrates after overall removal of previous coatings IS0 8502-3 preparation of steel substrates before application - Tests for assessment of surface cleanliness - Part 3: assessment of dust on steel substrates before application (pressure sensitive tape method) IS0 8503-1, preparation of steel substrates before application of paints - surface roughness characteristics of blast cleaned steel substrates - Part 1: specifications and definitions of ISO surface profile comparators for blast cleaned surfaces (ISO 8503-2), preparation of steel substrates before application of paints - surface roughness characteristics of blast cleaned steel substrates - Part 2: comparison of grading methods for blast cleaned surfaces (ISO) 8503-4, steel surface treatment before coating - surface roughness characteristics of spray cleaned steel - Part 4: calibration method of surface profile comparator, determination method of surface profile and method of stylus instrument - 3 General requirements for steel surface treatment - quality of steel surface treatment directly affects coating The surface impurities will lead to premature failure of the coating, and the surface roughness will affect the adhesion between the coating and the steel surface The general requirements for steel surface treatment are: A sand blasting cleanliness grade is sa212 b The surface dust level shall not be higher than 3 c The surface roughness is rz25-5o μ M 4 The surface treatment process is based on the characteristics of the container production process The steel surface of the container is pre coated in the workshop The steel plate is automatically shot blasted before forming and assembling, and then coated with a shop primer of about 10 μ M After the steel plate forming, assembly and final assembly are completed, the secondary sandblasting is carried out, and then the whole container painting process is started 4.1 raw material inspection: inspect the original condition of raw materials to see if there is rust, oxide scale and other pollutants According to ISO 8501-1, the corrosion grade of raw materials is divided into four grades: A, B, C and D grade C and D steels are not suitable for use If the steel is seriously rusted or a large number of stubborn attachments remain, it shall be scrapped 4.2 before entering the flat shot blasting machine, all the steel materials for oil removal must be cleaned of oil stain to ensure that there is no visible oil and dirt on the surface 4.3 shot blasting is the most effective and commonly used method for container steel pretreatment, and automatic shot blasting is usually used In order to achieve a certain surface quality, attention should be paid to: A select the appropriate abrasive and the appropriate abrasive ratio Commonly used abrasives are: water chestnut sand, steel shot, steel wire section, etc b Change Abrasives frequently to maintain a certain particle size c Remove the fine particles, rust and dust from the abrasives d Compressed air and abrasives shall be free from water, oil and other pollution After shot blasting, the surface cleanliness of steel is sa212, and the surface roughness is rz25 ~ 50 μ M Dust and other residues shall be removed by high-pressure air purging or vacuum cleaning before painting shop primer 4.4 shop primer coating and drying shop primer are the first protective coating after steel surface treatment The interval between shot blasting and coating shall not exceed 4 hours If it exceeds, shot blasting shall be carried out again If the drying conditions and ventilation conditions are not conducive to the rapid drying of the primer, in order to prevent paint sticking, it can be properly dried 4.5 when forming, assembling and assembling steel plates, attention shall be paid not to make the surface which has been surface treated and pre primed polluted again, and proper measures shall be taken to prevent dust and moisture when stacking in the workshop 4.6 after a large number of secondary sandblasting welding, there will be welding fume, spatter and paint around the weld Burn and other defects, the weld itself is too rough to paint, and there will be oil pollution and dust pollution in the construction process Therefore, after the completion of the general assembly, the steel around the weld and the part with surface defects shall be cleaned for the second time, and the manual sandblasting method is usually used in the sandblasting room Before sandblasting, the welding and gas cutting defects must be cleaned and repaired by appropriate methods, such as spatter, uneven weld, sand hole, air hole, incomplete penetration, etc the uneven weld shall be polished, trimmed and sharp corners removed by hand tools After sandblasting, the dust and oil stain on the surface shall be removed The dust shall be removed by compressed air blowing or vacuum cleaning The oil stain shall be cleaned by organic solvent 4.7 after the inspection and repair of the secondary sandblasting, the defects of the spraying surface, especially the weld defects, shall be inspected and repaired again In addition to routine observation of weld defects, light leakage inspection shall also be carried out Methods: enter the box, close the door for observation; mark the parts with light leakage and repair them before painting For some areas that do not meet the requirements of surface pretreatment, iron brush and hand tools can be used for repairing Local defects shall reach the surface cleanliness ST3 level after being repaired by hand grinding wheel 5 Inspection of surface treatment 5.1 the inspection of steel surface cleanliness shall be carried out in accordance with ISO 8501-1 Under moderate lighting conditions, the normal vision shall be observed directly without the aid of a magnifying glass Surfaces conforming to sa212 shall be free from visible grease and dirt, scale, rust, paint coating and foreign matter Any remaining trace shall be only a slight spot or stripe Please refer to photos a SA2 12 and B SA2 12 in the comparison standard 5.2 refer to ISO 8502-3 for the inspection of the dust on the steel surface, and use the method of pasting transparent adhesive tape to inspect The steps are: A select a test area b Take a piece of colorless transparent tape with a width of 25-30mm and a length of no less than 50mm, and stick it to the test area with fingers (not nails) c Slowly remove the tape and put it on the white paper for auxiliary reference d Compare the tape with the reference sample of iso8502-3, which is not darker than grade 3 5.3 the inspection of steel surface roughness shall be carried out according to the provisions of IS0 8503-1, IS0 8503-2 and IS0 8503-4, and the comparative sample block method or instrument measurement method shall be adopted Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,