7 Major Problems of Steel Structure Anti-corrosion Coating

Base surface cleaning → primer coating → top coat coating. (Try to choose automatic equipment such as: shot blasting machine sand blasting machine sand blasting room automatic sand blasting machine and other mechanical equipment; can effectively improve the adhesion of the product surface).

I. Base surface cleaning

(1) Check whether the steel structure production and installation are accepted before painting. Remove rust, weld spatter, oil, dust and so on from the parts to be painted before painting (weld sand blasting machine).

(2) In order to ensure the quality of painting, use automatic sand blasting machine-automatic sand blasting room-automatic shot blasting and rust removing machine to remove rust. The descaling method is to use the pressure of the compressor, continuous impact with the steel components of the surface of the rigid shot, the steel surface of the rust, oil and other debris cleaned up, revealing the metal steel color of a descaling method. This method is a high efficiency, thorough rust removal, more advanced rust removal process.

II. Primer coating

(1) Mixing and antirust paint, controlling the viscosity, consistency and thinness of the paint, and mixing sufficiently when blending, so that the paint color and viscosity are consistent.

(2) When spraying the first layer of primer, the direction of painting should be consistent and the rubbing should be neat.

(3) Spray paint when the bottom of the use of hard moving, short moments away from the principle of preventing too much spray paint and flow down.

(4) to be the first dry, and then spray the second, the second spray direction and the first direction perpendicular to the direction, which will make the film thickness uniform.

(5) after spraying on the components according to the original number labeling, major components also need to mark the weight, center of gravity position and positioning mark.

III. Top coat painting

(1) Painting materials should be according to the design requirements, shall not change varieties, and should pay attention to the nature of the bottom and top coatings compatible.

(2) The top coating should be carried out only after the site installation is finished, and the dust and other debris on the surface of the steel structure should be treated before the top coating is applied.

(3) Topcoat modulation need to choose the same color of topcoat, blending thinners appropriate, topcoat should be fully stirred before use, to maintain uniformity of color, its working viscosity, consistency should ensure that the coating does not fall, do not show the brush pattern.

(4) The top coat should be stirred continuously during the painting process, and the painting method is the same as the direction primer.

Ⅳ. Coating inspection and acceptance

(1) post-coating inspection, should be painted color consistency, bright and shiny color, not Zoupi, not pimples.

(2) surface coating construction and construction, the coated work to protect against flying dust and other debris.

(3) the determination of the thickness of the paint film coating, with the corner of the paint film thickness gauge to determine the thickness of the paint film, paint film thickness gauge general determination of the thickness of 3 points, take the average value.

V. Finished product protection

(1) After the steel structure is painted, it should be isolated by temporary enclosure, and it is forbidden to step on it and damage the coating.

(2) After the steel structure is painted, in case of gale or rain within 4 hours, it should be covered to prevent dust and moisture from sticking and affecting the adhesion of the coating.

(3) When the components need to be transported after painting, attention should be paid to prevent bumping and dragging on the ground, which may damage the coating.

VI. Should pay attention to the quality of the problem

(1) The construction drawings indicate that the parts that are not painted and the installation of weld joints in the range of 30~50mm wide, should not be painted. The friction surface of high-strength bolt connection shall not be painted within the range.

(2) Coating operation temperature should be between 5 ~ 38 ℃ is appropriate, when the temperature is lower than 5 ℃, select the appropriate low-temperature coating material coating. When the temperature is higher than 40 ℃, stop coating operations, or after treatment and then coating operations.

(3) When the air humidity is greater than 85% or the surface of the component has condensation, shall not carry out the coating operation, or after treatment and then carry out the coating operation.

(4) Before the steel structure is made, the hidden parts on the members and the parts of the structural interlayer which are difficult to be descaled are descaled in advance and coated in advance.

VII. Safety issues to be noted

(1) Workers who take part in steel structure production and painting should be familiar with the safety and technical operation regulations of this work type, and it is strictly forbidden to operate after drinking, meanwhile, open fire is strictly forbidden at the construction site and fire-fighting equipment is equipped according to the regulations.

(2) All kinds of machines must be used and maintained according to the instruction manual, and the machines with manned machine fixing requirements must be opened by a special person. Non-licensed personnel shall not be operated casually, and overloading of all kinds of machineries is strictly prohibited.

(3) the stacking and assembling of steel components, must be firmly fixed card, move over the pry bar point to be padded stable, rolling or sliding, the front may not stand people.

(4) sand blasting machine to remove rust, nozzle joints firmly, not allowed to people, nozzle clogging, should be shut down to eliminate the pressure before repair or replacement.

(5) sand blasting room rust removal to achieve non-pollution; automatic recycling; individually equipped with a filter cartridge dust removal system workers operating in the automatic sand blasting room can be 5-10 times more efficient than outdoor operation, which is now the main purpose of many manufacturers to choose the sand blasting room!