Assembly Conveyor Line Planning: Cracking the Bottleneck of Cache Backlog and Flexibility under 60JPH High Beat

I. Beat planning: from theoretical computation to dynamic tuning of the path of breakthroughs

A new energy vehicle company's new factory was blocked by the production line after commissioning, and the original design of 60JPH beat was only 45JPH in reality. diagnosis was found.Beat imbalance stems from three blind spots::

  1. ​Static calculations ignore mixed production losses​
    Traditional beat formula:TT = (60 × working days × shifts × working hours per shift) / annual production capacity.. However, multiple platforms need to be stacked when mixing productionDynamic compensation factor::

    • For each additional model difference, the station density needs to be increased by 0.2 (e.g., from 1.8 to 2.0 for mixed production of cars/SUVs).
    • Test case: Guangqi New Energy throughsegmental beat progression(Interior line 58 seconds → Chassis line 54 seconds → Final line 62 seconds), eliminating cross-section waiting and increasing the tempo by 22%

  2. ​Hidden timing traps at bottleneck stations​
    Chassis fitting station due to battery pack positioning timeout (±3mm accuracy requirement resulted in an average operation time of 68 seconds), solution:

    • ​dual mode synergy: AGV lifting battery packs (load 1.5 tons) + friction line synchronized conveyor body, precision error control within ±1mm.
    • ​​man-machine engineeringmake superior: Customized lifting pedal (height adjustment range 300mm), reducing the time for workers to bend down to pick up materials.

  3. ​Absence of an exception response mechanism​
    A plant's leaky bolts caused a line stoppage, exposing theDeficiencies in beat protection mechanisms::

    Image Code
    graph LR  
A[Equipment failure] --> B{cache margin>30Minutes?}  
B -->|Yes| C[Alternate Roller Bed Channel Enabled]  
B -->|No D[Activate ANDON system call support]  
D --> E[Technician responds within 10 minutes]  
    

    #svgGraph67593899342642{font-family: "trebuchet ms",verdana,arial,sans-serif;font-size:16px;fill:#333;}@keyframes edge- animation-frame{from{stroke-dashoffset:0;}}@keyframes dash{to{stroke-dashoffset:0;}}#svgGraph67593899342642 .edge-animation-slow {stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 50s linear infinite;stroke-linecap:round;} #svgGraph67593899342642 .edge-animation-fast{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 20s linear infinite;stroke-linecap:round;}#svgGraph67593899342642 .error-icon{fill:#552222;}#svgGraph67593899342642 .error-text{ fill:#552222;stroke:#552222;}#svgGraph67593899342642 .edge-thickness-normal{stroke-width:1px;} #svgGraph67593899342642 .edge-thickness-thick{stroke-width:3.5px;}#svgGraph67593899342642 .edge-pattern-solid{stroke- dasharray:0;}#svgGraph67593899342642 .edge-thickness-invisible{stroke-width:0;fill:none;}#svgGraph67593899342642 .edge- pattern-dashed{stroke-dasharray:3;}#svgGraph67593899342642 .edge-pattern-dotted{stroke-dasharray:2;}#svgGraph67593899342642 .marker{fill:#333333;stroke:#333333;}#svgGraph67593899342642 .marker.cross{stroke:#333333;} #svgGraph67593899342642 svg{font-family: "trebuchet ms",verdana,arial,sans-serif;font-size:16px;}#svgGraph67593899342642 p{ margin:0;}#svgGraph67593899342642 .label{font-family: "trebuchet ms",verdana,arial,sans-serif;color:#333;} #svgGraph67593899342642 .cluster-label text{fill:#333;}#svgGraph67593899342642 .cluster-label span{color:#333;} #svgGraph67593899342642 .cluster-label span p{background-color:transparent;}#svgGraph67593899342642 .label text, #svgGraph67593899342642 span{fill:#333;color:#333;}#svgGraph67593899342642 .node rect,#svgGraph67593899342642 . node circle,#svgGraph67593899342642 .node ellipse,#svgGraph67593899342642 .node polygon,#svgGraph67593899342642 .node path{ fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#svgGraph67593899342642 .rough-node .label text,#svgGraph67593899342642 .node .label text,#svgGraph67593899342642 .image-shape .label,#svgGraph67593899342642 .icon-shape .label{text-anchor:middle;} #svgGraph67593899342642 .node .katex path{fill:#000;stroke:#000;stroke-width:1px;}#svgGraph67593899342642 .rough-node . label,#svgGraph67593899342642 .node .label,#svgGraph67593899342642 .image-shape .label,#svgGraph67593899342642 .icon-shape . label{text-align:center;}#svgGraph67593899342642 .node.clickable{cursor:pointer;}#svgGraph67593899342642 .root .anchor path{ fill:#333333!important;stroke-width:0;stroke:#333333;}#svgGraph67593899342642 .arrowheadPath{fill:#333333;} #svgGraph67593899342642 .edgePath .path{stroke:#333333;stroke-width:2.0px;}#svgGraph67593899342642 .flowchart-link{stroke :#333333;fill:none;}#svgGraph67593899342642 .edgeLabel{background-color:rgba(232,232,232, 0.8);text-align:center;} #svgGraph67593899342642 .edgeLabel p{background-color:rgba(232,232,232, 0.8);}#svgGraph67593899342642 .edgeLabel rect{opacity. 0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#svgGraph67593899342642 .labelBkg{background-color:rgba( 232, 232, 232, 0.5);}#svgGraph67593899342642 .cluster rect{fill:#ffffde;stroke:#aaaa33;stroke-width:1px;} #svgGraph67593899342642 .cluster text{fill:#333;}#svgGraph67593899342642 .cluster span{color:#333;} #svgGraph67593899342642 div.mermaidTooltip{position:absolute;text-align:center;max-width:200px;padding:2px;font-family:" trebuchet ms",verdana,arial,sans-serif;font-size:12px;background:hsl(80, 100%, 96.2745098039%);border:1px solid #aaaa33; border-radius:2px;pointer-events:none;z-index:100;}#svgGraph67593899342642 .flowchartTitleText{text-anchor:middle;font-size: 18px;fill:#333;}#svgGraph67593899342642 rect.text{fill:none;stroke-width:0;}#svgGraph67593899342642 .icon-shape, #svgGraph67593899342642 .image-shape{background-color:rgba(232,232,232, 0.8);text-align:center;}#svgGraph67593899342642 .icon -shape p,#svgGraph67593899342642 .image-shape p{background-color:rgba(232,232,232, 0.8);padding:2px;}#svgGraph67593899342642 . icon-shape rect,#svgGraph67593899342642 .image-shape rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232, 232, 0.8);}#svgGraph67593899342642 :root{-mermaid-font-family: "trebuchet ms",verdana,arial,sans-serif;}
    

    是
    

    

    否
    

    

    equipment failure
    

    

    Cache margin > 30 minutes?
    

    

    Enable alternate roller bed access
    

    

    Activate ANDON system call support
    

    

    Technician response within 10 minutes
    

    

    By setting theHierarchical Cache Threshold(e.g., 15% reserved for dynamic caching in the interior-chassis transfer area), reducing line downtime by 40%.

Cache Design: How Intelligent Scheduling Solves the Logistics ”Intestinal Obstruction”

When the daily production capacity of the assembly plant exceeded 800 units, a German car company sufferedlogistical crisis--The accumulation of empty material frames at the line edge blocks the channel. The key to its breakthrough lies in the construction ofThree-level caching neural network::

▶ Scenario 1: Contingency plan for material outages

  • ​Electronic label + circulation conveyor line: implantation of RFID chips in material frames to provide real-time feedback on material consumption (e.g., photoelectric counters at battery pack installation stations)
  • ​Dynamic replenishment algorithm: When the inventory at the work station is <2 hours of usage, the system automatically triggers SPS trolley distribution, which is prioritized above the new material frame on line

▶ Scenario 2: Cache Optimization for Multi-Model Mixing

make a copy of
Caching strategy for new energy models:
Battery pack assembly area → 2 hours of caching in standing storage (to prevent battery self-discharge)
Caching strategy for conventional models:
Engine sub-assembly line → platen lineCache 1.5 hour dosage  


pass (a bill or inspection etc)Independent caching by model(math.) genusSpace utilizationLift 35%


▶ Scenario 3: Zero-wait convergence for work order switching


The pain point of a factory that took 47 minutes to change lines by​Intelligent Dispatch System​Breaking:


    

  1. When the current work order completes 80%, the MES system pushes the bill of materials of the next work order.
    2. 

  2. Material system with pre-loaded frames and temporary storage in elevated buffer table (lifting height 1.2 m)
    3. 

  3. The moment the old work order ends, the new frame is cut into the main line through the shuttle car
    
​effect: Line changeover time compressed to 8 minutes, capacity loss reduced by 82%
    4. 





Flexible Layout: AGV+Modular Island Subverts Traditional Production Line


When the new models of Chang'an UNI series were introduced, the cost of remodeling the traditional skateboard line exceeded 20 million dollars. Converted toFlexible Layout ProgramAfter that, the investment was reduced to $6 million:


1. Dynamic workstation reorganization technology


    

  • ​AGV grid layout: Deployment of 152 lifting AGVs in a 200 x 80m workshop to form a programmable track
    • 

  • ​Workstation Adaptive Case::

    make a copy of
    Sedan mode: station spacing 4.8m (compatible with 4-door assembly)
SUV mode: station spacing 5.2m (compatible with 7-seat third row installation)  
    

    Switching time <3 minutes by laser SLAM localization
    • 



2. The modularization revolution in the dispensing islands


    

  • ​quick-change interface design: ISO standard flange (positioning pin diameter Ø20±0.01mm) is used for the powertrain assembly island.
    • 

  • ​Mixed-line production performance::
    

    


    
Dispensing Module
Number of Compatible Models
Time-consuming switching

    
    


    
Battery Pack Carrier
3 models
45 seconds

    

    
Seat rail mounting machine
5 models
28 seconds.

    
    

    

    • 



3. The flexibility gene of the factory of the future


Linear motor technology is starting to disrupt tradition (accuracy ±0.1mm/speed 3m/s), but is limited by cost (2.3 times that of AGVs).Transition program::




Critical stations (e.g. windshield gluing) use”Steel-based track + magnetic navigation AGV”Composite structure, not only to protect ± 0.5mm positioning accuracy, but also than all linear motor program to save 60% investment






IV. Synergistic effectiveness mapping: the coupling of the three main points


Image Code
flowchart TD  
A[Beat design] --> B{cache capacity calculation}  
B -->|Beat Boost10%| C[Cache needs to be expanded by 25%]  
C --> D[Layout flexibly modified]  
D -->|AGVOrbital Expansion A  


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Beat Boost 10%




AGV track extension




Beat design




Cache Capacity Calculation




Cache needs to be expanded by 25%




Layout Flexibility Retrofit




Empirical data: when the beat is increased from 45JPH to 60JPH, the buffer zone needs to be increased from 90 to 120 stations, and the AGV path needs to be increased with more cross-traffic.




​Breaking through cognitive boundariesSAIC Ningde Base uses the iron triangle model of ”Beat - Cache - Flexibility” to realize 4 platforms and 12 models of co-production, and the space utilization rate reaches 1.8 times of the industry average - proving that flexible layout is not a cost burden, but a pivot point for capacity leap. This proves that flexible layout is not a cost burden, but a pivot point for capacity leap.

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