A collection of questions about purchasing concrete laser levelers / leveling

    The hydraulic system of the concrete laser leveling is its "heart" and "muscle", responsible for driving all key actions such as the lifting, vibration, movement of the leveling head and the extension and retraction of the boom. A scientific and rigorous maintenance plan for the hydraulic system is the core to ensuring the reliability, accuracy and long service life of the equipment. The following is a well-structured and highly operational correct maintenance plan for the hydraulic system of a concrete laser leveling: More than 70% of the faults in the hydraulic system are caused by oil contamination (particles, water, air) and excessively high oil temperature. Therefore, the maintenance plan should revolve around "keeping the oil clean and cool". Oil level check: When the equipment is parked on a level ground and all oil cylinders are retracted, check the oil level gauge of the hydraulic oil tank to ensure that the oil level is between the upper and lower limits marked. Low oil level can cause the pump to run dry, the system to overheat and components to be damaged. Visual inspection Leakage inspection: Quickly inspect the oil pump, valve block, cylinder piston rod, all pipe joints and hose surfaces for visible oil leakage or dripping. Pipeline inspection: Check for any abnormal bulges, wear, cracks or friction with adjacent components in the hydraulic hose. Start preheating: In cold weather, after starting the engine, it should be run at medium to low speed without load for 3 to 5 minutes to allow the hydraulic oil to circulate and heat up, improve fluidity, and prevent dry grinding of components. Cleaning and inspection: After the operation, check whether the oil filling port of the hydraulic oil tank, the vent valve (breather), and the surface of the hydraulic components are contaminated by cement mortar. Clean them in time to prevent contaminants from entering the system. Temperature perception: Before shutting down, use the back of your hand to sense whether the temperature of the fuel tank and the main valve blocks is abnormally hot to the touch (usually not exceeding 80℃). Continuous high temperatures will accelerate the oxidation and deterioration of the oil. This is the main body of the maintenance plan. It must be carried out strictly in accordance with the intervals in the manufacturer's manual and detailed records must be made. Maintain the project Period/Frequency Specific operations and standards Hydraulic oil replacement First replacement: 200 to 500 hours after a new machine or major overhaul. 1. Change the oil while it's still hot: Perform this when the equipment has just been shut down and the oil temperature is still hot. Regular replacement: Every 1,000 to 2,000 working hours or once a year (whichever comes first). 2. Thorough empting: Drain the old oil from the fuel tank and oil lines. If necessary, flush with fresh oil. The cycle needs to be shortened under harsh working conditions. 3. Clean the fuel tank: Use a non-fibrous cloth to clean the inner wall of the fuel tank and the magnetic drain plug. 4. Strict oiling: Add new hydraulic oil of the specified grade and viscosity level to the prescribed oil level through a high-precision filter. Replacement of the oil suction/return oil filter element Every 500 hours or simultaneously with each oil change. When replacing, pay attention to cleaning the area around the filter element seat to prevent dirt from falling in. 2. Never reuse the filter element after cleaning it. High-pressure pipeline filter (if any) Alarm according to the clogging indicator on the filter, or as stipulated in the manual (usually synchronized with the oil change cycle). Timely replacement and checking the type of residue on the filter element can help determine the internal wear condition of the system (for example, if there is a lot of metal shavings, there may be abnormal wear of components). Hydraulic oil quality testing Every 6 months to 1 year (applicable to high-value or high-intensity usage equipment). Samples are sent to a professional laboratory for oil spectral analysis to detect water content, contamination degree, acid value and metal wear particles. This is the most effective means of predictive maintenance, which can detect potential faults in advance. System tightening and inspection Monthly or every 250 hours. 1. Inspect and tighten all pipe joints, flanges and valve block installation bolts (in accordance with torque requirements). 2. Check all the piston rods of the oil cylinders for any scratches, rust or bends. Minor scratches should be repaired immediately with an oilstone. 3. Check the pre-charge pressure of the accumulator (if any). Cooling system cleaning Weekly or depending on the cleanliness of the environment. Clean the fins of the hydraulic oil radiator to ensure there is no blockage from dust, willow catkins, cement powder, etc., to guarantee the heat dissipation efficiency. This is the key to controlling the oil temperature. Overloading is strictly prohibited: Avoid the leveling machine operating at its maximum load for a long time, as this will cause excessive system pressure and a sharp increase in oil temperature. Avoid shock: Operate the control handle smoothly to reduce the shock load on the hydraulic system. Cylinder protection: During operation, pay attention to protecting the piston rod to avoid direct impact or scratches from concrete or crushed stones. Proper parking: When parked for a long time, all cylinders (especially the exposed piston rods) should be retracted to reduce corrosion and deformation. High-temperature environment: Enhance the cleaning of the radiator. Consider using hydraulic oil with higher viscosity (as recommended in the manual), and add auxiliary cooling if necessary. High humidity/water environment: Strengthen the inspection of oil level and water content in oil products, and keep the vent valve of the oil tank dry. The replacement cycle of the filter element can be shortened. In extremely cold environments: Use low pour point hydraulic oil. The equipment should be parked in a warm warehouse and fully preheated before startup. Park the equipment in a dry room and completely retract all the oil cylinders. Fill the fuel tank to the brim to reduce the formation of condensation on the inner walls. Start the engine every month and let the hydraulic system run idle for 10 to 15 minutes to lubricate all components and remove moisture. Slow and weak operation: It may be due to low oil level, pump wear, or malfunction of the main relief valve. Abnormal system noise (pump beeping) : It may be due to clogged oil suction filter element, excessively high oil viscosity, pump suction or cavitation. Abnormal increase in oil temperature: cooler blockage, severe internal leakage, improper oil level, and the set value of the relief valve being too high. Cylinder crawling or shaking: Air inside the system, leakage from the cylinder, or oil contamination causing the valve core to get stuck. Stop the machine immediately for inspection: If any of the above abnormalities occur, stop the machine immediately and start checking from the simplest aspects such as oil level, filter element, and leakage. Eliminate operating while faulty: Hydraulic system failures can deteriorate in a chain reaction, and minor issues can quickly turn into major overhauls. Professional maintenance: Complex operations such as pressure adjustment and disassembly of pumps and valves should be carried out by professional maintenance personnel. Before disassembling any hydraulic components, the system pressure must be completely released. Strictly adhere to the cycle: execute by the hour or calendar, and establish maintenance logs. Oil product management is at the core: only specified oil products are used, strictly filtered, and regularly replaced and tested. Cleanliness is the top priority: keep the oil clean, the refueling process clean, and the radiator clean. Pay attention to detailed inspection: Daily visual and tactile checks can detect most early problems. Equal emphasis on operation and maintenance: Standardized operation is the fundamental way to prevent abnormal stress in the hydraulic system. Ultimately, please be sure to take the manufacturer's regulations in your equipment's "User and Maintenance Manual" as the primary basis, and formulate and implement your maintenance plan in combination with your specific working conditions.   Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.    

As construction units continue to increase their requirements for the color, appearance, and flatness of large-area concrete floors, the problems of traditional construction processes in terms of construction progress and quality are becoming increasingly prominent. The use of concrete laser leveling machines for one-time floor forming construction has far greater advantages in terms of process, technology, and cost than the former. In order to effectively improve the operating efficiency of concrete laser leveling machines, this article briefly summarizes some methods and techniques from the perspective of purchase and maintenance, hoping to help everyone's future use. ✪ How to judge whether the quality of a laser leveling machine is good? 1. Look at the effect. High-quality laser leveling machines have more stable effects. 2. Look at the speed. High-quality laser leveling machines have faster leveling speeds. 3. Look at the accuracy. High-quality concrete laser leveling machines have higher leveling accuracy. 4. Look at the model. The selection of a suitable laser leveling machine is mainly based on the construction site and area. 5. Look at the manufacturer. The technical strength of the manufacturer of concrete laser leveling machines directly affects the quality of the equipment. 6. Look at safety. When selecting a laser leveling machine, the braking performance and operational safety of the concrete laser leveling machine must also be fully considered. ✪✪How to judge whether the laser leveling machine is a new equipment? 1. Check whether there is noise during operation. Hold the inner sleeve of the bearing body of the concrete laser leveling machine with your left hand, and turn the outer sleeve with your right hand to make it rotate, and listen to whether there is noise during the operation of the bearing. Since most counterfeit products are produced under backward conditions and are completely operated in a manual workshop, it is inevitable that impurities such as dust and sand will be mixed into the bearing body during the production process, so there will be noise or unsmooth operation when the bearing rotates. 2. Check whether there is oil stain on the surface. This should be paid special attention to when purchasing. Since the current anti-rust technology is still a little behind that of foreign manufacturers, many manufacturers are prone to leave thick oil stains when anti-rusting concrete laser leveling machines, and there will always be a sticky touch when directly touching them with your hands. 3. Check whether the printing on the parts is clear. The bearing products of each laser leveling machine are usually printed with their words, numbers, etc. The counterfeit fonts are not only blurred, but also float on the surface due to the rough printing technology. Some can even be easily wiped off by hand or have serious manual traces. 4. Check whether the outer packaging is clear. Generally speaking, the concrete laser leveling machines produced by regular manufacturers have their own dedicated designers to design the outer packaging, so the whole machine packaging should be very clear from lines to color blocks. ✪✪✪How to judge whether the laser leveling machine needs overhaul? Due to the great differences in the operating conditions and maintenance levels of different concrete laser leveling machines, it is difficult to determine the reasonable overhaul time based on the service life and working time alone. According to many practical results, we recommend that the laser leveling machine generally needs an overhaul after working for 4000-6000 hours. Machinery that needs overhaul usually has the following symptoms: 1. The pipelines and sealing components of the hydraulic system are aging and the oil leakage is serious. 2. The circuits of the electronic control system are aging, the control accuracy is reduced, and the failure rate is high. 3. The engine power is significantly reduced, and symptoms such as blowby, burning oil, and difficulty in starting appear. 4. The concrete laser leveling machine has been working for about 5000 hours, but its transfer case, transmission, and reducer have never been repaired; 5. The hydraulic power of the leveling machine has decreased, which is generally manifested as insufficient walking power or material distribution power. Specifically, it is basically normal for small load operations, barely able to operate with medium loads, but unable to operate with large loads. Warm reminder: Choosing the right model and ensuring the performance of the machine are important prerequisites for the safe use of the concrete laser leveling machine, and learning maintenance skills is a necessary requirement to maintain the good operation of the laser leveling machine and extend the service life of the machine, so both aspects need to be given enough attention.

    The determination of the initial setting time of concrete and the entry timing of laser levelings are directly related to the quality, efficiency and cost of floor construction. Now I will provide you with a detailed analysis of these two core points. The "initial setting" of concrete is a physicochemical process, referring to a point in time when concrete begins to transform from a plastic state to a solid state, rather than a period of time. In terms of standards, the initial setting time refers to the period from the moment water is added and mixed until the concrete loses its fluidity and begins to set. Judgment methods and criteria This is the method stipulated in the national standard (GB/T 50080), which is usually carried out in the laboratory or at important construction sites. Method: Use a penetration resistance meter to penetrate the mortar screened out from the concrete mixture at a specified speed. When the penetration resistance reaches 3.5MPa, the corresponding time is the initial setting time. Advantages: The data is precise, objective and reliable. Disadvantages: It requires dedicated equipment, the operation is rather complicated, and it is not suitable for on-site rapid judgment. In actual construction, workers and technicians mainly rely on the following empirical methods to make judgments: Acupressure method (the most classic) : Apply a slight pressure to the concrete surface (usually with the thumb). The criterion for judgment: If, after pressing with a finger, a clear mark about 2-3 millimeters deep can be left on the surface, and the concrete is not sticky to the hand, with no obvious water marks or slurry overflow around, it is considered to have reached the initial setting state at this time. State analogy: It feels like moist clay or plasticine. Scratch method Make a mark on the concrete surface with a nail, a screwdriver or your finger. The criteria for judgment: The scratch marks are clear, the edges are neat, and the bottom of the scratch can maintain its shape and will not be quickly filled and healed by the slurry. Footprint method A person walks on the concrete and observes the footprints. Judgment criteria: The depth of the footprints should be around 5 to 10 millimeters, and there should be no obvious cracking or excessive bleeding around the footprints. Vibration rod insertion method Insert the small vibrator into the concrete and then pull it out. The criterion for judgment: The hole formed after being pulled out can basically remain in its original state and will not collapse and close rapidly. Important note: The on-site experience method requires construction personnel to have certain experience. The best practice is to make a comprehensive judgment by combining multiple methods and compare it with the estimated initial setting time provided by the laboratory. The entry timing of the laser leveling must be closely coordinated with the setting state of the concrete. Entering the market too early or too late can lead to serious problems. Question Sinking: The tracks or wheels of the leveling may get stuck in the concrete, causing deep ruts and disrupting the flatness. Bleeding: The equipment's rolling will force water and fine particles to float up, forming a surface slurry layer, which leads to dusting, sanding and insufficient strength in the later stage. The concrete cannot support the weight of the equipment, and the leveling head cannot be effectively leveled. Instead, it will disrupt the concrete. Condition description: The fingerprinting mark is very deep (>5mm), or the footprint is deeply sunken, and the scratch heals rapidly. Question Construction difficulties: The resistance of the leveling machine's movement is huge, the engine load is high, and it may even be unable to move. Poor surface quality: The flat head cannot effectively smooth out the already hardened surface, leaving marks of roughening and cracking, which damages the integrity of the surface. Poor joint: It cannot bond well with the subsequent poured concrete, resulting in cold joints. Ineffective compaction: The concrete has lost its plasticity, and the vibration of the leveled head cannot make it compact again. Condition description: There is almost no mark when pressed by finger, or a very strong force is needed to leave a shallow mark. The edge of the scratch will crack. The laser leveling should be put into operation when the concrete reaches the initial setting state, or slightly earlier than the initial setting (that is, close to the initial setting but not yet fully reached). Specific timing to grasp Core standard: When using the finger press method and the depth of the finger press impression is around 3-5mm, it is the best time for the leveling to enter the site. Operation process connection: The ideal construction process is: The preparatory processes: concrete spreading, initial vibration, and leveling with scraping bars have been completed. Wait for the right moment: Let the concrete stand naturally, bleed water and evaporate, gradually developing towards the initial setting state. During this period, workers can carry out manual operations such as edge and corner treatment. Judgment and entry: The construction supervisor continuously observes the condition of the concrete. Once it reaches the aforementioned "golden finger pressure standard", they immediately direct the laser leveling machine to enter the site. High-efficiency operation: The leveling, with its highly efficient functions of scraping, vibrating and leveling, can quickly complete large-scale operations when the concrete is still plastic but capable of supporting the weight of the equipment at its optimal state. Prediction is key: Before construction, it is necessary to understand the mix ratio of the concrete to be used and the estimated initial setting time measured in the laboratory (for example, at 20℃, the initial setting time of ordinary concrete is approximately 4 to 6 hours). This provides a time reference for on-site judgment. Environmental factors: Temperature, humidity and wind speed have a significant impact on the initial setting time. High temperature, strong wind and low humidity will shorten the initial setting time. It is necessary to prepare in advance to reduce the waiting time. Conversely, it will be extended. Personnel and Communication: A designated person (such as a foreman or technician) must be assigned to determine the initial setting time and maintain smooth communication with the equipment operator. It's better to arrive a little earlier than too late: When it's impossible to make an accurate judgment, entering the site a little earlier (the concrete is slightly softer) might just require dealing with the track indentations. However, if the entry is too late and the concrete becomes too hard, the quality problems caused are almost irreversible and the handling cost is extremely high. In short: When you "feel" the concrete with your hand and it feels like a moist and solid piece of clay, that's the best time for the laser leveling to shine. Accurately seizing this opportunity is the core technology for creating high-level and high-quality concrete floors. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.