Common Problems and Solutions of Hot-melt Coating
The main role of the road markings are the implementation of lane road, through the drawn lines on the road traffic signs to guide different types of vehicles at different speeds along a designated route prevails so as to improve road transport capacity and reduce traffic The purpose of the accident; instructions and notices to the driver through the traffic markings to predict road conditions and clarify their use and access roads of the rights and obligations and methods; for law-abiding and law enforcement to provide a legal basis.
Highway marking paint mainly using the following categories: solvent-based coatings, heat-based coatings, hot melt coating (also known as melt coatings), two-component coatings, water-based paint and other types.
The highway construction, used for traffic engineering in the road marking paint material requirements of high performance. First requires drying time is short, simple operation, in order to reduce traffic interference; Second, the demand against the reflective ability, bright, reflective high, in order to have a good day and night visibility; third, it has good slip resistance and wear resistance in order to ensure road safety and marking life. The hot-melt-type reflective coating of its features is a quick-drying, drying time for 1-3min. The synthetic resin will be colored pigments, physical pigments, reflective materials, combined with the road surface, with strong adhesion, stable performance, color, degree of brightness and reflective characteristics of a long time, and it has good wear resistance and slip resistance. Therefore, highway construction in China road marking materials, mainly in hot melt coatings and hot melt vibration reflective coating.
On the highway construction, road marking, we often encounter the problem of some kind or another. I am through learning and practice and in the long-term highway construction has accumulated some experience, the following hot-melt coating on the construction of several common problems and solutions with you to look at exploring:
Discoloration issues
1. Melting temperature is a too high or hot-melt process of burning the bottom of the kettle. The solution would be to strictly control the temperature, the operation carried out before the end of hot-melt tank cleaning.
2. The substandard quality of the product itself is likely to paint deterioration. Number of products in the professional inspection prior to the construction sector should be tested, qualified only after the construction of the use of.
Night reflective ineffective problem
1. issue a poorly reflective at night. Construction, the wind was being blown towards the larger glass beads; Spreader machine rocking tilt causes uneven surface scattering glass bead spreading. The solution is to install the windscreen glass Bo Sabu machine and make a coating operation of preparatory work, to master the speed of construction progress.
2. Premixed and surface impurity scattering glass beads too much into the circle rate is low, particle size distribution is poor, coating liquid does not meet the technical requirements, inadequate viscosity, softening point is too low and other reasons, will result in the phenomenon of night-time reflective ineffective. These are all products of inferior quality. Should be used in the construction of qualified products.
Crack problem
1. Winter construction, coating case of cold-shrink, resulting in stress, this stress concentration at one point, easy to crack; the emergence of cracks due to the cold season and coatings and construction related to the performance, but also related to the situation with the road surface. In particular, the newly paved road with fragile cement mortar layer, or conservation of film, easy to crack. How to prevent cracks due to cold, we should first select the appropriate construction season, try to avoid the cold winter marking construction. At the same time pay attention to the rational use of a hot-melt coating, different seasons and their corresponding paint selection ratio. Newly laid cement road surface, curing time should be 2 weeks or more, the road on the conservation of fragile plaster layer or film, road marking should be cleaned up before construction.
2. Subgrade reflection cracks cracks.
Roadbed material generated by expansion or contraction cracks, or cracks due to uneven subsidence caused road markings such as cracks. Under normal circumstances can not be avoided, can enhance the quality of roadbed construction.
3. Road softened produced cracks in some places in summer temperature of 40 ℃ or above, high-temperature asphalt pavement under the hot sun can reach 60 ℃ or above, asphalt softened, while the coating is relatively hard, at the wheel impact load that may arise under the soft-road crack. Produce soft pavement cracks is the direct cause of the soft and hard surface coatings and the extent does not match the shock loads generated, should be an appropriate adjustment formula can ease.
4. The coating is a coating of surface crack after construction, the surface irregular mesh cracks, this crack depth shallow, but often a basis for further development as the aging of cracking, so that coating damage. To prevent coating the surface of dry, we should start a good selection of compatible resins and additives to start, pay attention to the temperature control of the construction.
5. Due to the aging S-line cracks. Surface of the coating material degradation and natural weathering, so that marking cracks, aging marking paint cracks but also because long-term exposure on the road to withstand sun and rain, spring, summer autumn and winter, temperature difference between day and night and seasonal temperature changes, subjected to ultraviolet light role, subject to cyclical expansion and contraction arising. Cracks generated due to aging can only start from the selection of suitable coating to prevent premature aging coating, in the standard line of construction, strict control of temperature, to ensure the quality of pre-construction surface treatment to prevent foaming.
6. Microporous and bubbling Because of the hole in the air, water or dry the next Paint, in the coating under high temperature caused by expansion or vaporization. Expanding the gas bubble is caused by coating from the top, the porous coating is the expansion of gases, leaving behind holes pierced, so that coating the more common defects. Wet pavement porous and increase the chances of blistering, it is because the road is full of water or moisture in porous, high-temperature coating so that the water left in the micro-gasification and expansion of micro-bubbles formed, the next Paint contains some of low boiling point components, easy to dry when the residue in the cavity was dry in the next Paint when the temperature coating, the play to the rapid gasification of the material expansion, the formation of micro-bubbles under the paint by. Microporous, marking not only affect the appearance of blistering but also reduced the coating and the surface area of reality and seriously affect the paint adhesion and longevity. Therefore, opt for a variety of good fluidity of paint. To ensure dry and full sunshine after the rain has to go through before construction. Choose dry the next Paint fast, strictly control the temperature should pay attention to the construction with the ambient temperature.
Skin peeling off from the problem
1. Pavement breaks in the skin from the phenomenon. Adjustable coating formulations to increase the bond strength and flexibility
2. Road sweeper does not clean, not thorough, or not to use the next Paint. The construction procedure should be strictly in accordance with the construction to ensure construction quality
3. Under the Paint coating for a prolonged period without drawing a line (or sandstorm weather, construction) and easy to glue dust, can cause skin marking off date; the next Paint painting immediately after drying marking.
4. S-line coating moisture level of impact by road, the road there is water, or more humid must take measures to dry and after construction. To ensure that road construction should be dry, in exceptional circumstances, must meet deadlines, can be dried by artificial means;
5. Ambient temperature is below 5 ℃, the construction quality and unstable, prone to peeling off, melting temperature are too low, will seriously affect the standard line and the cohesive force of the road; if not handled under the Paint, the environment should the temperature at 10 ℃ the above construction is better. Paint coating to the surface temperature should not be less than the instantaneous 180 ℃; construction should be considered a winter's day from 10 am to 3 pm during the environmental temperature is not too low.
6. Paint melting inadequate mixing inequality. Construction of paint should be fully melted, stir well, and aging full post before being coated;
7. Cement road surface paint by the inappropriate choice of a new road paved with concrete and brittle due to surface layer of large and there is basic, easy-off from skin.
Should use permeable concrete pavement under the Paint treatment can improve adhesion strength. The new poured cement pavement careful cleaning.
Wear resistance problem
1. Road marking wear and traffic volume are directly related to the size. Traffic is heavy, large vehicles are more frequent lane changing sections, the general wear and tear on the fast road marking. In addition, the roads are sand and gravel over the dirt there, it will speed up the marking of the wear and tear. Marking wear resistance and paint itself, is the regulation of production formula, adding some wear fillers such as quartz sand.
Hot melt marking to ensure a longer life, we must choose according to different climatic conditions, paint formulations, buy quality and reliable performance and stable raw material. In the melting process in the strict control of temperature, stirring evenly, in the construction process, master the marking of construction speed, to ensure the uniformity of thickness to keep the road clean.
S-line deformation and tooth edge
1. Is mainly tire indentation and scar. We should choose suitable viscosity and good fluidity of high-quality paint. Strengthen the construction management, coating completely dry open traffic.
2. Coating the surface of vertical stripes, due to hot-melt coating in the heat generated in the process of local burning may also be mixed with a foreign body. In addition, the paint bucket or paint defects notch cinder attachment, it will also result in vertical stripes. Surface in poor conditions will directly affect the quality of marking the appearance affect the reflective effect at night. This first paint should she surface with a lateral stripe is due to paint bucket slot vibration, coating viscosity is too large road causes of inequality. Should master the construction of temperature, hopper tank scraper timely inspection and processing. Thoroughly cleaning the road, the construction carts should avoid fighting tank shock.tart heating and melting, strict temperature control, does not allow for burning, and foreign matter mixed. The pre-construction deal with slot machines and the Big Dipper to conduct a thorough inspection and cleaning, so that in a normal state.