The heavy-duty plate feeder is a key equipment for conveying raw materials at
the front end of large-scale quartz sand production lines (daily processing
capacity ≥ 3000t). It is responsible for smoothly conveying quartzite waste
materials (particle size ≤ 1200mm) from mining to the coarse crusher (required
conveying capacity ≥ 500t/h, material flow fluctuation ≤ 8%), directly
determining the continuity and capacity stability of subsequent crushing
processes. If there is a delay in conveying (more than twice a week) and uneven
material flow, it will cause the coarse crusher to overload and stop, the
production line to cut off materials, and significantly reduce production
efficiency. Based on the characteristics of high density (2.65g/cm ³) and strong
impact of quartzite waste, a three-step optimization plan is summarized to
improve the operational stability of the plate feeder.
Step 1: Optimize the chain plate structure and wear-resistant configuration,
and strengthen the conveying carrying capacity
Insufficient wear resistance, loose connections, or roller failure of the
chain plate material are the core causes of conveyor lag, and targeted
optimization and adaptation to heavy load requirements are needed.
Optimization of chain plate and pin shaft adaptation: ordinary carbon steel
chain plate is selected, which wears quickly in the face of quartzite impact and
is prone to deformation after thinning the chain plate thickness by more than
5mm; Insufficient lubrication of the shaft leads to jamming and increased
running resistance. Replace the high manganese steel wear-resistant chain plate
(thickness ≥ 20mm, surface quenching treatment), and increase the wear
resistance by more than 3 times; Adopting an "automatic lubrication system" to
regularly lubricate the pin shaft, ensuring sufficient lubrication and reducing
operational friction resistance; The connecting bolts of the chain plate are
made of high-strength alloy steel, and the pre tightening torque is controlled
at 250-300N · m to avoid loosening and falling off during operation.
Optimization of idler and guide rail: Poor sealing of idler bearings,
intrusion of quartz sand dust causing jamming, and exacerbation of conveying
jamming when more than 2 idler failures occur per meter; The wear of the guide
rail exceeds 3mm, and the running trajectory of the chain plate deviates,
resulting in side wear and jamming. Replace the sealed wear-resistant roller
(with a bearing protection level of IP65), check the flexibility of the roller
rotation every quarter, and replace the failed roller in a timely manner; Weld a
wear-resistant alloy layer (thickness 5mm) on the surface of the guide rail,
calibrate the parallelism deviation of the guide rail to ≤ 0.5mm/m, and ensure
that the chain plate runs smoothly without deviation.
Step 2: Calibrate the parameters of the drive system to improve the stability
of power transmission
Insufficient driving power, speed fluctuations, or brake failure can lead to
insufficient conveying power and uneven material flow, requiring precise control
of system parameters.
Optimization of drive system adaptation: Single motor drive is selected, and
when facing heavy loads, the power is insufficient (less than 110kW), which
makes it easy to stall during startup; The speed fluctuation exceeds 5r/min, and
the material flow rate fluctuates rapidly. Replace the dual motor synchronous
drive system (total power 132-160kW) to enhance the heavy-duty starting
capability; Equipped with a frequency converter to stabilize the conveying speed
at 0.3-0.5m/s, dynamically adjust according to the load of the coarse crusher,
and control the fluctuation of the material flow within 5%; Install a speed
monitoring device to provide real-time feedback on the operating status, and
automatically calibrate when the deviation exceeds 3r/min.
Optimization of braking and tensioning system: Brake wear leads to brake
failure, and material flow backflows and impacts the equipment during shutdown;
Insufficient tension of the chain plate (below 80kN), resulting in chain
skipping and jamming during operation; Excessive tension causes the chain plate
to stretch excessively. Replace the electromagnetic brake (braking torque ≥ 250N
· m), regularly check the wear of the brake pads, and replace them in a timely
manner when the thickness is less than 3mm; Adopting a "hydraulic automatic
tensioning device" to stabilize the tension of the chain plate at 90-110kN,
automatically compensating for the tension of the chain plate and avoiding
tension imbalance.
Step 3: Optimize feed control and buffer protection to ensure uniform and
stable material flow
Overloaded feed volume, uneven fabric distribution, or insufficient buffering
can exacerbate material flow fluctuations and equipment impact, requiring
effective front-end control.
Feed quantity and fabric control: If the feed quantity exceeds the rated
value (such as rated 500t/h, actual 600t/h), the chain plate will overload and
cause jamming; The feeding port is not equipped with a fabric feeder, resulting
in concentrated accumulation of waste materials and local overload. Monitor the
feed rate with a laser level gauge and use a vibrating feeder for precise
control to maintain the feed rate at 85% -95% of the rated value; Install a
curved fabric baffle to evenly distribute the raw materials along the width of
the chain plate, and control the thickness of the material layer within
300-500mm to avoid local overload.
Buffer protection and raw material pretreatment: There is no buffer device at
the feed inlet, and the raw materials directly impact the chain plate, with an
impact force exceeding the limit of the chain plate's bearing capacity (≥ 50kN);
Mixing oversized blocks of raw materials (with a particle size exceeding 1500mm)
into the raw materials can easily cause jamming at the feed inlet. Install a
polyurethane buffer bed (thickness ≥ 100mm) at the feed inlet to reduce impact
force by more than 30%; Install a mesh screen (with a diameter of 1200mm) to
remove oversized waste materials and avoid material jamming; Install a scraper
plate at the front end of the chain plate to clean the adhered fine sand and
reduce operational resistance.
Daily maintenance should pay attention to: checking the wear of the chain
plate, the operation status of the drive system, and the uniformity of the
material flow every day; Clean up the debris on the rollers and guide rails
every week, and check the tightening of bolts; Monthly calibration of tension
and conveying speed, replacement of aging seals; Conduct comprehensive
maintenance on the drive motor and reducer every quarter. By implementing the
above measures, the stuttering rate of the conveyor can be reduced to less than
once per month, and the fluctuation of the material flow can be stabilized
within 5%, ensuring continuous and efficient raw material transportation at the
front end of the large-scale quartz sand production line.