Domestic concrete laser levelling machine manufacturers

Acceptance standards for quality concrete in building floor projects 1. General principles 1.1 Purpose This standard clarifies the specifications and standards for quality concrete acceptance of building ground projects to ensure that the project quality meets the design requirements and is safe to use. 1.2 Scope of application This standard applies to the acceptance of concrete materials in building ground projects, including requirements for raw materials, construction technology, quality inspection and acceptance, and safe and civilized construction. 2. Material acceptance standards 2.1 Cement When using cement, cement with product quality certificate and on-site inspection report should be selected, and on-site acceptance should be carried out in accordance with regulations. After the cement enters the site, it should be stored separately according to different varieties, labels, and factory dates, and signs should be set up. It is strictly prohibited to use expired, damp, or agglomerated cement. 2.2 Sand and stone Sand and stone should meet the design requirements, be free of impurities such as silt and stone powder, and have particle size and gradation that meet specification requirements. For projects with special requirements, special sand and stone should be used. 2.3 Water When using tap water or well water, make sure the water is clean and free of impurities such as oil, acid, and alkali. The chloride ion content in water should not exceed specification requirements. 2.4 Admixtures Admixtures should meet the design requirements, have product quality certificates and on-site inspection reports, and undergo on-site acceptance in accordance with regulations. The type and dosage of admixtures should comply with the design and specification requirements and should not contain ingredients harmful to the human body. 3. Construction process acceptance standards 3.1 Template installation Design calculations should be carried out before the formwork is installed, and the formwork should be made and installed in accordance with the design requirements. The strength and stiffness of the formwork should meet the construction requirements, and the joints should be tight, smooth, and free of slurry leakage. The formwork support system should be firm and stable and must not tilt or shake. After the formwork is removed, the surface should be kept clean and free of residue. 3.2 Steel bar binding Rust removal treatment should be carried out before the steel bars are bound. The specifications, models, quantities and spacing of the steel bars should meet the design requirements. The steel bars should be tied firmly and not loose. The joints of the steel bars should comply with the specification requirements, and the welding quality should comply with the design and specification requirements. The thickness of the protective layer of steel bars should meet the design requirements. When cement mortar pads are used, the number of pads should not be less than 4/m2. 3.3 Concrete pouring Before pouring the compacted soil, the formwork, steel bars, etc. should be inspected to ensure that they meet the construction requirements. The slump of concrete should comply with the design and specification requirements, and no water or additives should be added to the mixer at will. When pouring the compacted soil, it should be carried out in layers. The thickness of each layer should not be too large, and it should be vibrated densely without vibration leakage. After the concrete pouring is completed, the surface should be polished and compacted in time to prevent cracks. 3.4 Maintenance After the concrete pouring is completed, curing should be carried out in time, and the curing time should not be less than 7 days. During the curing period, the concrete surface should be kept moist to prevent shrinkage cracks. When using cover watering for curing, the frequency of watering should be enough to keep the concrete in a moist state. When using plastic film for curing, the plastic film should remain completely sealed and water-tight. After the curing is completed, the formwork should be removed promptly and the finished product should be protected in accordance with regulations. 4. Quality inspection and acceptance standards 4.1 Essentials The quality of building ground engineering should comply with the design requirements and relevant specifications, and the surface should be smooth, smooth, and free of cracks, pitting and other defects. The dividing joints should be neat and straight, and there should be no staggered joints. There should be no leakage at the junction between the floor and the wall. Ground engineering with functional requirements should meet the requirements of relevant functional functions.

    When developing maintenance standards for concrete construction equipment, it's necessary to consider the technical characteristics of each equipment type (such as mixing equipment, conveying equipment, pouring equipment, and vibrating equipment), construction scenario requirements, and industry standards. This approach aims to create a systematic standard that covers the entire lifecycle, is quantifiable and implementable, and assigns specific responsibilities. The following is the specific framework and core content: Before developing standards, it's important to first clarify the underlying foundations to ensure they are legally compliant, practical, and avoid being divorced from equipment characteristics or industry requirements. Equipment Technical Documentation Based on the manufacturer's operating and maintenance manuals, key parameters (such as lubrication cycles, replacement thresholds for wearing parts, and maintenance tool models) are extracted. For example, for a mixer, "mixing blades should be replaced if wear is ≤3mm" and "gear oil should be changed every 500 hours for the reducer" are standard "technical baselines." Industry and national standards Reference mandatory or recommended specifications, such as: Technical Regulations for Safety in the Use of Construction Machinery (JGJ33-2012): Clarifies safety requirements for equipment maintenance (such as powering off before maintenance and posting warning signs); Technical Specifications for Concrete Mixing Plants (Buildings) (GB/T 10171-2021): Specifies maintenance cycles and performance testing indicators for mixing equipment; Technical Specifications for Concrete Pumps (GB/T 13333-2014): Clarifies maintenance requirements for the hydraulic system and piping of concrete pumps. Construction scenarios and equipment load Based on project specific adjustments (e.g., high temperature, high humidity, or high-frequency construction scenarios require shortened maintenance intervals): For example, for concrete mixer trucks in tropical regions, the hydraulic oil filter replacement interval needs to be shortened from the standard 1,000 hours to 800 hours. For example, when continuously pouring large volumes of concrete, the insulation layer of the vibrator needs to be inspected every 8 hours instead of every 8-hour shift. Concrete construction equipment varies greatly. Based on the principle of "classification and standardization," the standard should be broken down into "equipment classification modules." Each module covers four dimensions: daily maintenance, scheduled maintenance, fault prevention, and safety requirements, ensuring coverage of the entire equipment lifecycle. Using the four most critical types of equipment in concrete construction as examples, this standard specifies specific maintenance content, cycles, standards, and responsible individuals: Device Type Maintenance Dimension Maintenance cycle Core maintenance content (quantifiable standards) 1. Mixing equipment (mixing machine, batching machine, cement silo) Daily Maintenance Daily before/after construction 1. Mixer: Clean any remaining concrete in the drum (no lumps or adhesion), and check the blade/liner fastening bolts (no looseness, torque ≥ 80 N·m). 2. Batching machine: Clean any debris from the hopper, and check the conveyor belt for deviation (≤ 50 mm/10 m). 3. Cement silo: Check the sensitivity of the level gauge (analog signal response time ≤ 2 seconds), and the safety valve for leaks.   Periodic Maintenance (Medium Repair) Every 300-500 man-hours 1. Replace the mixer liner (if wear ≥ 5 mm). 2. Change the gear oil in the reducer (oil quality test: viscosity ≥ 220 cSt, no metal debris). 3. Adjust the tension of the batching machine conveyor belt (deflection ≤ 15 mm/1 m span).   Periodic Maintenance (Major Repair) Every 2000-3000 man-hours 1. Disassemble the mixer shaft and check the bearing clearance (≤ 0.05 mm). 2. Calibrate the batching scale for accuracy (error ≤ ±1%). 3. Repair the anti-corrosion coating on the cement silo interior (no rust on ≥ 0.1 m2). 2. Conveying equipment (concrete pump trucks, trailer pumps, mixer trucks) Daily Maintenance Daily after construction 1. Pump Truck: Flush the delivery pipeline (no concrete residue, smooth water flow), check the outrigger cylinder seals (no oil leakage, no scratches on the piston rod); 2. Mixer Truck: Clean the tank (no hardening on the tank wall), check the tire pressure (±0.2 bar).   Periodic Maintenance Every 1000 km / 500 man-hours 1. Pump Truck: Replace the hydraulic oil filter (pressure differential ≥ 0.3 MPa), inspect the boom welds (no cracks, weld height ≥ 8 mm); 2. Mixer Truck: Replace the tank liner (wear ≥ 10 mm), and maintain the drive system (bearing temperature ≤ 60°C). 3. Vibrating equipment (insertion vibrator, flat plate vibrator) Daily Maintenance Every 8-hour shift 1. Check the cable insulation (no damage, ground resistance ≤ 4Ω); 2. Vibrator: Test run (amplitude ≥ 0.8 mm, no abnormal noise), and check the connectors for looseness.   Periodic Maintenance Every 50 shifts 1. Replace the vibrator bearing (clearance ≥ 0.1 mm); 2. Clean the motor cooling vents (no dust blockage, temperature rise ≤ 40°C). 4. Measuring equipment (sand and gravel scales, cement scales, admixture scales) Daily Maintenance Daily 1. Clear the scale hopper of any accumulated material (no material hanging, no skew); 2. Calibrate the zero point (error ≤ ±0.5kg) and check the sensor wiring (no looseness).   Periodic Maintenance Every 30 days 1. Perform dynamic calibration (load 100% of the rated weight, error ≤ ±1%); 2. Check the sensor protection (no moisture, no deformation due to impact). Lubrication Management Standards Follow the "Equipment Lubrication Chart" (specify the lubricant type, filling point, cycle, and amount). For example, use 3# lithium-based grease for the mixer bearings, refilling every 100 working hours at a rate of 50g each time. After lubrication, record the "lubrication time, person performing the lubrication, and oil quality" to avoid over-lubrication or under-lubrication. Consumable Parts Management Standards Maintain a "consumable parts ledger" (including model, inventory threshold, and replacement cycle), such as for agitator blades, conveyor belts, vibrators, and cables, with a minimum inventory of three sets. When replacing consumable parts, "model matching" is required. Substitution with non-genuine parts is prohibited (exceptional circumstances require approval from the technical director). After replacement, a test run is required to confirm compliance. Safety Maintenance Standards Before maintenance, power and gas must be turned off, and a warning sign must be posted (e.g., "Equipment under maintenance, do not start"). Safety belts must be worn and a warning area must be set up for overhead work (e.g., pump truck boom maintenance). Electrical equipment maintenance requires a "certified operator" (electrician's license). Hydraulic system maintenance must be depressurized (reduced to 0 MPa) to prevent hydraulic fluid spray and injury. Record and traceability standards Establish an "Equipment Maintenance Record Form" (electronic or paper) that includes: equipment number, maintenance date, maintenance items, test data, abnormalities, person responsible, and inspector. Record retention period should be ≥ the equipment's service life to facilitate tracing the cause of a malfunction (e.g., if a mixer blade breaks, the record can be used to verify whether it has not been replaced beyond the specified time limit). Clarify the responsibility system Responsibilities are divided into different levels: Operators are responsible for "daily maintenance" (cleaning, inspection, and simple tightening); repair workers are responsible for "regular maintenance" (disassembly, replacement, and calibration); technical leaders are responsible for "standard review and exception handling"; and project managers are responsible for "resource support (spare parts, tools, and funding)." A "Equipment Maintenance Responsibility Letter" is signed, linking maintenance effectiveness to performance appraisals (e.g., if equipment failure occurs due to inadequate maintenance, the responsible individual's performance will be deducted). Supervision and Inspection Mechanism Daily Inspections: Technicians will spot-check the Maintenance Record Form daily and verify maintenance effectiveness on-site (e.g., randomly checking the wear of the mixer blades to see if it matches the records). Regular Assessments: Monthly "Equipment Maintenance Evaluations" are conducted, rewarding teams/individuals with a maintenance compliance rate ≥95%. Those failing to meet the standards will be given a deadline to rectify the situation. Fault Review: After equipment failure, analysis will be conducted to determine whether the cause was maintenance failure, and standards will be updated (e.g., if a crack on a pump truck boom was caused by untimely weld inspection, the weld inspection cycle will be shortened). Personnel Training Standards New employees must pass "equipment maintenance training + practical assessment" (e.g., identifying wearing parts of the mixing unit and completing maintenance records) before they can begin work. Maintenance skills training is organized quarterly (manufacturer technicians are invited to explain key maintenance points and common troubleshooting for new equipment) to ensure personnel skills meet standard requirements. Concrete construction equipment technology evolves rapidly (e.g., new intelligent mixing plants and electric pump trucks), necessitating regular standard updates: Update Cycle: A comprehensive review is conducted annually. Revisions are required immediately if equipment upgrades, construction scenarios change, or industry standards are updated. Update Process: The technical department collects equipment failure data, maintenance feedback, and new regulatory requirements. Discussions are held with maintenance workers, operators, and manufacturer representatives. After revisions are made public, training sessions are held to ensure full awareness. The standards established through the above framework can not only cover the technical requirements of equipment, but also be implemented in specific positions and operations, avoiding "empty" concepts and ultimately achieving the goal of "reducing equipment failures, extending service life, and ensuring construction continuity."   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.      

  The construction plan of the laser leveling machine is as follows Requirements for the base surface: The base surface must be firm, compacted, without settlement, cracking, no oil stains, no plastic film, no other paint, latex paint, bubble gum and other residues on the ground, and the base surface must be flat without large ups and downs, no bumps, honeycombs, or cement lumps. 1. Rolling of the bare soil, requiring compaction and flatness error of 2~3cm∕2m. 2. Pad construction: Use C15 fine stone concrete to cast a 6 cm thick pad layer, vibrate with a vibration pump, and the surface does not need to be smoothed. The flatness is maintained at 2cm∕2m. (This item is optional) 1. Ground treatment After the general contractor and the relevant construction parties have cleared away the large building materials and garbage in the construction area where the 6 cm cushion layer has been laid and handed it over to us, we will first clean up the dust in this area. If there is paint or other foreign matter that is not easy to combine with concrete on the ground, we must do everything we can to remove it. Then rinse the ground with water, and there must be no floating dust. If the base layer is higher in special places, it should be chiseled off with an electric pick or air compressor. 2. Preliminary measurement of elevation According to the basic elevation points given by the general contractor or Party A, the elevation of representative locations in the entire area is initially measured with a level to see how much the thickness of the concrete differs from the thickness required by the owner. (This measurement should be as many points as possible, otherwise it is not representative). In most cases, since the flatness of the base layer is not well controlled, once the elevation is measured, it can be seen how thick and thin the thick and thin parts and the thickness of most concrete are. If the thickness of most concrete exceeds the contract thickness, or is much lower than the contract thickness, the situation should be reported to the superior truthfully and a solution should be requested before the next step of construction can be carried out. 3. Rebar binding For the thicker 20cm thick floor poured in this project, according to the design requirements, double-layer bidirectional reinforcement is generally required. The reinforcement arrangement requires Φ12@150*150, and the upper and lower layers are connected by horse stools. The distance between horse stools is 1 meter. The surface layer reinforcement is 3~4 cm away from the floor elevation. In order to prevent the floor from settling, it is recommended to set up an integral continuous steel mesh. Or pour in separate compartments, but use force transfer rods to connect the plates. The force transfer rods can be Φ20@1000 round steel bars, with a spacing of 400. 4. Formwork 1.) According to the elevation confirmed by Party A, the template position is determined according to the floor drain position and water collection well position listed in the drawings and the slope requirements. This project is in an underground garage, and there may be a slope requirement, so the template can use angle irons of different specifications from Ф6.5*6.5*5 to Ф3*3*2 as the template. Use large specifications for thick concrete and small specifications for thin concrete. According to the designed slope, the compartment casting method is adopted. 2.) The leveling of this project needs to be leveled by a laser leveler. The uniform high-frequency vibration of the laser leveler makes the concrete floor dense and avoids the stress concentration caused by deformation and cracking of the floor. When using a laser leveler for leveling, you only need to make the frame template of each piece. When supporting the formwork, first use an ink fountain to pop up the template control line on the base ground. The line is appropriately wider than the edge of the future compartment seam by 1~2 cm, so that after the formwork is removed, the side seam is not straight due to local damage, and it can also be trimmed. If it can be guaranteed that the side seam after each demolding is a straight line, the template can also be directly supported on the natural seam of the future axis. 3.) On the control line, drill holes on the ground with an electric hammer every one meter or so. Generally, a 12×200 drill bit is used, and the penetration depth is about 14 cm. 4.) Nail the steel bars with a diameter of 12 mm cut into 14 cm each section into the drilled holes. It is required to be firmly driven until it can hardly be driven down. 5.) Place the angle iron near the firmly driven steel bars along the line direction. First, use wood or bricks to pad the two ends of the angle iron. The approximate height is about the same as the elevation. Then one person looks at the level, one person holds the tower ruler, and another person uses a wooden wedge to fine-tune the height of the angle iron at any time according to the elevation. After reaching the same elevation, the electric welder spot welds the angle iron to the top of the steel bar. Then weld the other end of the angle iron in the same way. After both ends are welded, weld the middle part of the angle iron. After welding, check the elevation of one side again. 6) Brush the template oil (waste engine oil) on the supported template to facilitate demoulding. 7) After the compartment formwork is supported, the angle irons are welded around the water collection well. The upper end of the angle iron should be consistent with the floor slope of the compartment, and ensure that water is concentrated to the water collection well from multiple directions. 8) The construction method of the angle irons at the edge of the water collection well for the first floor with only floor drains but no water collection well and car ramp is the same as in Article 7.