An asphalt paving machine is an integral piece of equipment for any job that involves the creation of new asphalt surfaces, as its specifications have an enormous influence over project efficiency and quality. Best way to find the Asphalt companies Mesa.
Maintaining a consistent head of material over the mat is of primary concern to an operator and requires accurate regulation of conveyor speed, augur distribution system, and flow gates.
Power Sources
Asphalt Paving Machine Power Solutions vary based on the size and scale of the operation. A popular option is using diesel-powered engines; other possible sources include gas engines, electric motors, and battery-powered pavers.
Modern pavers typically utilize a tracked chassis with front and rear wheels connected via power hydraulic mechanisms for maximum maneuverability and eliminating hand paving. Furthermore, this chassis allows them to be driven directly from the job site to the job site rather than being trailed across various distances.
Tracked asphalt pavers are ideal for large road construction projects, offering superior traction on unimproved surfaces while offering more stability when working on steeper slopes than wheeled equipment.
A standard asphalt paving machine typically comprises a hopper, conveyor, and distribution augers. The hopper acts as a temporary storage area for HMA delivered via truck; additionally, it features hinged side compartments called wings, which can be raised and lowered to funnel material towards its center, where the conveyor system will then take it.
As part of your paving effort, it’s crucial that the hopper only partially empties. Doing so could cause cold, large aggregate to flow down the conveyor in concentrated masses instead of mixing with hot, fine aggregate on the mat – leading to temperature differentials, which create isolated low mat densities and uneven density distribution across your project site.
Control Systems
Paving is a complex process requiring precise measurement and control to achieve quality. Achieving the correct thickness is crucial while creating a smooth surface. A paver’s screed unit controls how much material is extruded by the machine.
Asphalt is stored in a hopper and heated using either propane burners or electric heaters to keep it at an optimum temperature for paving. Material flow monitoring systems help regulate how often hot aggregate is fed from its storage bin into conveyors and augur distributors from within its hopper.
Paving equipment also helps protect workers from harmful fumes produced during paving operations. Fume emission control systems work to mitigate toxic fumes at their source by filtering volatile organic compounds (VOCs) out of the mixture before entering the machine, effectively decreasing asphalt fume emissions during this process.
Other equipment is often employed to improve paving results, including reference systems that move with the paver and touch the road surface in order to measure existing pavement grade or ultrasonic devices that don’t connect but gather elevation data via a series of sonic pulses. With these measurements at hand, pavers can automatically set their screed plate at an appropriate height and inclination so as to match existing road surfaces.
Materials Flow
Accurate materials flow is crucial to performing quality paving work. If the amount of HMA coming out of the drills varies significantly, screed placement will become less precise, leading to bumpy or diverted mats with stops where the machine paused briefly.
Material flow systems manage conveyor speed and auger feed rates to maintain a constant head of asphalt delivery to the screed, using either an integrated controller or sensor to regulate it. Controllers like AC700MC use ultrasound waves to continuously track asphalt production – eliminating mechanical sensors that become clogged up with sticky mixture over time while requiring minimum maintenance costs.
Heater hoppers are used to keep HMA at an appropriate temperature for paving. Asphalt is fed into these hoppers using either slat conveyors or auger conveyors, with metal slat conveyors having greater capacities for handling high volumes than auger conveyors. Augers distribute material evenly by way of inlet vents located at both ends of their support rods, as well as outlet vents in the back. They may be operated in either single- or dual-axis configuration and powered via hydraulic motors via the right drive chain sprocket and right auger sprocket, respectively.
Compaction
Contractors employ different approaches to estimate round-trip transportation times between their asphalt plant and job site and calculate how many loads a paver can transport per unit of time. Productivity when it comes to laying asphalt mixes, however, can be more unpredictable as its success often depends on environmental conditions during placement and compaction – such as air temperature, base temperature, rate of cooling down of mix composition as it oxidizes, etc. This factors into how much time is available for compaction.
To maximize compaction from each roller pass, the breakdown roller(s) on paving machines must be placed as close to their paver as possible in order to optimize compaction with each roller pass. This allows them to keep pace with their paver without stopping and starting, thus decreasing the cycle count. In addition, doing this also keeps breakdown roller(s) within their ideal rolling zone for mixed compaction before it begins cooling below cessation temperature and prevents premature cessation.
Intermediate and finish rollers often follow behind breakdown roller(s). Their selection depends on what’s available in a contractor’s fleet; however, proper sequence, speed, and rolling pattern are crucial to reaching target density. Achieving consistent panel density at each stage is vital to reducing air voids and optimizing pavement performance; once opened to traffic, this further compacts the mat and prevents deformation and rutting.
