Quality management of construction engineering of metal surface with mixed color paint
1. According to the standard:
"Unified Standard for Construction Quality Acceptance of Construction Engineering" GB50300-2001
"Code for Construction Quality Acceptance of Architectural Decoration Projects" GB50210-2001
2. Construction preparation
2.1 Material requirements
2.1.1 Coatings: varnish, varnish, lead oil, blended paint (magnetic blended paint, oily blended paint), varnish, alkyd varnish, alkyd enamel, antirust paint (red lead antirust paint, iron red anti-rust paint), etc.
2.1.2 Filling materials: gypsum, big white, floor yellow, laterite, black smoke, cellulose, etc.
2.1.3 Thinner: gasoline, kerosene, alkyd thinner, rosin, alcohol, etc.
2.1.4 Drying agent: cobalt drying agent and other liquid materials.
2.2 Main machines and tools:
2.2.1 Oil brush, knife, ox horn board, oil paintbrush, digging tool (a tool for brushing the upper and lower openings of doors and windows that are not easy to paint), copper wire basket, sandpaper, emery cloth, putty board, steel scraper, squeegee , small oil barrels, oil spoons, half-sized barrels, buckets, wire pliers, small hammers, wire brushes, high stools and scaffolding boards, safety belts, etc.
2.3 Operating conditions:
2.3.1 The construction environment should be well ventilated, the wet work has been completed and has a certain strength, and the environment is relatively dry.
2.3.2 Before large-scale construction, a model room should be made in advance, and the team can be organized to carry out large-scale construction after passing the inspection and appraisal of the relevant quality department.
2.3.3 Steel doors, windows and metal surfaces should be inspected before construction, and those that are deformed and unqualified should be replaced.
2.3.4 The handover inspection should be carefully carried out before operation, and the residual problems should be properly dealt with.
2.3.5 Before painting the finishing paint, all the glass needs to be installed.
3. Operation process
3.1 Process flow:
The above is the process flow of the intermediate practice of applying mixed color paint coatings on steel doors, windows and metal surfaces. If it is an ordinary mixed-color paint project, the method and process are basically the same. The difference is that except for one less paint, only the putty is found, and the putty is not satisfied. If it is a high-grade mixed color paint coating project, the method is basically the same as the process. The difference is that it is necessary to add a second pass of full putty scraping, polishing and brushing. After the third pass of paint, add water sandpaper to polish, wipe with a damp cloth, The fourth coat of paint can be used as a high-grade mixed color paint paint project.
3.2 Base treatment: cleaning, derusting, sanding paper. First, clean the floating soil, mortar, etc. on the steel doors, windows and metal surfaces. For steel doors, windows or metal surfaces that have been painted with anti-rust paint but have rust spots, use a spatula to remove the underlying anti-rust paint, then use a wire brush and emery cloth to effectively polish it, and then apply another layer of anti-rust paint. After the anti-rust paint dries completely , Scrape and smooth the trachoma, pits, missing edges, joints, etc. on steel doors and windows or metal surfaces with gypsum putty (the weight ratio of metal surface putty is gypsum powder 20, cooked tung oil 5, oily putty or alkyd putty 10. Primer 7, appropriate amount of water. The putty should be adjusted so that it is not soft, not hard, no honeycomb, and it is advisable not to fall when picking wires). After the putty is completely dry, sand it with No. 1 sandpaper, and wipe off the powder on the surface with a damp cloth after sanding the sandpaper.
3.3 Putty scraping: Use a knife or a squeegee to scrape the plaster putty on the steel doors, windows or metal surfaces (the mix ratio is the same as above), and it is required to scrape thinly, cleanly, evenly and without flying thorns. After the putty is dry, sand it with No. 1 sandpaper, pay attention to protecting the edges and corners, and it is required to achieve a smooth surface, straight lines and corners, and uniformity.
3.4 Brush the first coat of paint:
3.4.1 Brushing lead oil (or alkyd matte blending paint): lead oil is made of colored lead oil, varnish, clear oil and gasoline. The mixing ratio is the same as before. dry agent. The consistency of the oil should be suitable for covering the bottom, not flowing, and not showing brush marks, and the color of the lead oil should conform to the color of the model. When brushing the lead oil, start painting from the left side of the upper part of the frame. When brushing the oil on the frame side, do not brush to the wall. Pay attention to the color separation inside and outside, the thickness should be uniform, and the brush pattern should be smooth. After finishing the bright sub, brush the lower half of the frame. When brushing the window sashes, if there are two windows, the left one should be painted first and then the right one; if there are three windows, the middle one should be painted last. After the outside of the window sash is completely brushed, hook it with a stile hook and then brush the inside.
When brushing the door, first brush the gloss, then brush the door frame and the back of the door leaf. After brushing, use a wooden wedge to fix the lower opening of the door leaf. of paint wiped clean. It is necessary to focus on checking the corners of the line and the yin and yang corners for defects such as falling, missing brushes, wrapping edges, and bottoming out, and should be trimmed in time to achieve consistent color.
3.4.2 Apply putty: After the paint is completely dry, apply plaster putty to the shrinkage or incomplete part of the bottom putty. The requirements are the same as before.
3.4.3 Abrasive paper: After the putty is completely dry, sand it with No. 1 sandpaper. The requirements are the same as before. After grinding, wipe off the powder with a damp cloth.
3.4.4 Glass installation: see glass installation process standard for details.
3.5 Brush the second coat of paint:
3.5.1 Applying lead oil: Same as before.
3.5.2 Wipe glass and sandpaper: Use a damp cloth to wipe clean the inside and outside of the glass. Be careful not to damage the putty surface and splayed corners. The sandpaper should be lightly sanded with No. 1 sandpaper or old sandpaper, the method is the same as before, but be careful not to wear through the primer, and protect the edges and corners. The sandpaper should be cleaned after grinding, and the ground powder should be wiped clean with a damp cloth.
3.6 Apply the last blended paint: the oiling method is the same as before. However, due to the high viscosity of the blended paint, it is necessary to brush more and more when painting, and the oil should be full, not flow or drop, uniform in brightness, and consistent in color. When brushing oil on glass putty, wait for the putty to reach a certain strength before proceeding. The brushing action should be quick, the brush should be light, and the oil should be uniform, so as not to damage the smooth surface of the putty, and the eight-character line should be seen. After brushing the paint, it is necessary to check it carefully immediately. If there is any defect, it should be repaired in time. Finally, use stiletto hooks or wooden wedges to open and fix the doors and windows.
3.7 Winter construction: Winter construction of indoor paint and coating projects should be carried out under heating conditions, and the room temperature should be kept balanced. Generally, the ambient temperature of paint construction should not be lower than +10°C, and the relative temperature should be 60%, and sudden changes should not be allowed. At the same time, special personnel should be assigned to measure temperature and open and close doors and windows to facilitate ventilation and remove moisture.
4. Quality standards
Quality inspection standard for solvent-based paint finishing engineering
Item sequence Inspection items Allowable deviation or allowable value (mm) Inspection method Main control item 1 Coating quality Article 10.3.2 Check product qualification certificate, performance test report and entry acceptance record 2 Color, gloss, pattern Article 10.3 .3 Observation and inspection 3 Comprehensive quality of finishing Article 10.3.4 Observation and hand-touch inspection 4 Base treatment Article 10.3.5 Observation and hand-touch inspection: inspection of construction records - general item 1 Connection with other materials and equipment The interface should be clear Article 10.3.8 Observation and inspection 2 Colored paint finishing quality The color is uniform and uniform in ordinary finishing Observation and hand touch inspection Advanced finishing is uniform and smooth Gloss is uniform and smooth Ordinary finishing gloss is basically uniform and smooth without hand feeling Advanced finishing gloss is uniform and smooth Brush pattern Ordinary finish Brush pattern smooth Advanced finish Brushless finish Wrapped concealed wrinkled leather Ordinary finish is not allowed Advanced finish No decorative line, color separation line Straightness Ordinary finish 2 Advanced finish 1 3 Varnish finish Quality and color Ordinary finish is basically the same Observation and hand touch inspection Advanced coating is uniform and consistent Wood grain Ordinary coating brown eye leveling, wood grain is clear Advanced coating brown eye leveling, wood grain clear gloss, smooth Ordinary coating gloss is basically uniform and smooth without hand feeling Advanced coating gloss is uniform and smooth brush Texture Ordinary Finishing Brushless Texture Advanced Finishing Brushless Texture Wrapped Edges, Falling, and Wrinkled Skin Not Allowed Where Common Finishing Is Obvious
5. Finished product protection
5.1 Clean up the surrounding environment before painting to prevent dust from flying and affecting the quality of the paint.
5.2 After each coat of paint, the doors and windows should be hooked with stiles or fixed with wooden wedges to prevent the paint from sticking to the fan frame from affecting the quality and appearance, and at the same time prevent the door and window glass from being damaged.
5.3 Immediately after brushing the oil, wipe off the paint dripping on the ground or window sill and polluting the wall and hardware.
5.4 After the paint and coating project is completed, special personnel should be assigned to take care of and manage it, and no touching is allowed.
6. Quality problems that should be paid attention to
6.1 Missing paint and anti-rust: Anti-rust generally occurs in steel doors, windows and metal surfaces. The anti-rust paint is broken; the third is that the steel doors and windows or metal surfaces have not been carefully inspected before installation, and the rust removal paint and anti-rust paint have not been repaired. The latter is the main quality problem we should pay attention to.
Missing brushes mostly occur on the upper and lower heads of steel doors and windows and the hinge facets, as well as the upper and lower ends of door and window frames and seam strips. The main reason is that the installation of the inner door leaf is not well coordinated with the oiler, so it often happens that the door leaf is installed without painting the paint, and the oiler cannot paint it afterwards (unless the door leaf hinge is removed and repainted); there is also a steel screen door. And the steel screen window, the yarn is stretched without pre-painting the lead oil of the color separation, and the check is not strict, etc., often there is a phenomenon of less paint. Other missed brushing problems are mainly caused by the operator's carelessness.
6.2 Lack of putty, lack of sandpaper: generally occurs in hinge grooves, upper and lower risers, tenon joints and nail holes, cracks, knots and incomplete edges, etc. The main reason is that the operator did not carefully follow the process regulations to operate.
6.3 Flowing and wrapping: There are two main reasons: one is that the paint is too thin, the paint film is too thick or the ambient temperature is high, the paint is slow to dry, etc., which are easy to cause flow. The second is due to improper operation sequence and technique, especially at the edge color separation of doors and windows, if the oil volume is large and the operation is not careful, it is easy to cause flow and wrap.
6.4 Obvious brush marks: mainly due to the small size of the oil brush or the unsoaked oil brush, resulting in hard bristles. Apply a suitable brush and soften the oil brush with thinner before use.
6.5 Wrinkles: mainly caused by poor paint quality, uneven blending, fast solvent volatilization or high temperature, and adding drier.
6.6 Hardware pollution: In addition to careful operation and timely cleaning of small hardware and other contaminated parts, door locks, handles, and latches should be installed as much as possible (but the position and door lock holes can be drilled in advance) to ensure that the hardware is clean and beautiful.
6.7 Backlighting: due to uneven oil absorption speed or uneven surface of steel doors, windows and metal roofs, plus indoor humidity or primer not dry and excessive thinner, etc., local backlighting phenomenon of tarnished paint surface may occur.
7. Quality records
7.1 Factory certificate of paint and other materials.
7.2 The project quality inspection and evaluation form for this sub-item.