1. Why does thermoplastic paint produce lumps after melting?

Lumps and caking of thermoplastic paint during melting are very common in field construction. The main reasons include uneven heating, insufficient stirring and damp paint raw materials. If the heating temperature is too low, the paint cannot be fully fused, and residual solid particles will form small lumps. If the paint is stored in a humid environment for a long time, the moisture inside will cause partial agglomeration after heating.

In addition, long-time high temperature standing without stirring will cause local resin carbonization, forming hard black particles. These lumps will block the discharging gap of the marking machine, resulting in intermittent lines and uneven marking thickness. It is recommended to keep constant temperature stirring during melting, and store thermoplastic paint in a dry and ventilated warehouse.

2. Why does the road marking machine discharge paint intermittently?

Intermittent discharging of the road marking machine is mostly caused by machine blockage and unstable paint fluidity. Impurities, old paint residues and coked particles in the hopper will block the discharging scraper, making the paint unable to flow out smoothly. Meanwhile, if the thermoplastic paint viscosity is too high due to low temperature, the fluidity becomes poor, which will also cause discontinuous discharging.

Before construction, workers need to clean the hopper, filter and scraper thoroughly. Adjust the paint temperature to 180℃-220℃ to ensure uniform fluidity. If the machine still discharges unsteadily, check whether the walking wheel is stuck or the propelling speed is unstable.

3. Why are the painted lines wavy and not straight?

Wavy and distorted marking lines are mainly caused by unstable manual operation and equipment failure. Unstable pushing speed and shaking body of the hand-push marking machine will directly lead to irregular lines. In addition, worn guide wheels and unbalanced machine body will cause left and right deviation during walking.

Many construction teams do not pop baseline before construction and rely on visual judgment, which is the main cause of long-distance line deviation. To ensure straight and smooth lines, it is necessary to draw a reference line in advance, check the flexibility of the walking wheels before construction, and keep uniform walking speed during operation.

4. Why do new markings have poor reflective effect?

Poor night reflection of thermoplastic markings is not only related to glass beads, but also closely related to paint melting and machine construction. If the paint temperature is too high, the surface glass beads will sink completely and cannot form reflection points. If the temperature is too low, the beads cannot be embedded firmly and will fall off soon.

Unstable machine speed will also affect the artificial spreading time of glass beads. Only when the beads are spread within 2-4 seconds after the paint is formed can the best embedding depth and reflection effect be achieved. Using qualified thermoplastic paint with standard pre-mixed beads and high-quality drop-on beads can effectively guarantee long-term retroreflectivity.

5. Can the marking machine work normally in low temperature weather?

Low temperature weather will affect both thermoplastic paint performance and marking machine working state. When the temperature is lower than 5℃, the molten paint cools and solidifies instantly after being discharged, resulting in insufficient adhesion and easy cracking. At the same time, the mechanical flexibility of the marking machine will decrease in low temperature, and the walking resistance will increase, which may cause unsmooth discharging.

It is not recommended to carry out marking construction in ultra-low temperature environment. If the project is urgent, use low-temperature resistant modified thermoplastic paint, properly extend the stirring and heating time, and preheat the marking machine equipment before operation.

6. How to maintain the road marking machine after daily construction?

Daily maintenance of the marking machine directly affects the service life and construction accuracy. After each construction, the residual thermoplastic paint in the hopper, scraper and pipeline must be completely cleaned to prevent the paint from solidifying and blocking the equipment. Check the wear degree of the scraper and walking wheels regularly, and replace worn parts in time to avoid uneven discharging and wavy lines.

In addition, the equipment should be placed in a dry and ventilated place after use to avoid rain erosion and metal rust. Regular lubrication of mechanical moving parts can ensure flexible operation and stable construction effect for a long time.

Most construction problems of road markings come from improper thermoplastic paint melting and irregular marking machine operation. Standard paint melting temperature, clean equipment state and stable construction operation are the key to obtain flat, straight, wear-resistant and high-reflective road markings. Daily maintenance can effectively reduce equipment failure rate and improve project construction efficiency.