Best Practices for Material Transfer Operations

Transcription

1 1 Best Practices for Material Transfer Operations WINDROW PAVING OPERATIONS

2 Principles and Techniques 2 Quality Production Material Management Machine Setup Paving Tips Machine Features

3 Quality 3 Pavement smoothness Material consistency

4 Pavement Smoothness 4 Uniform, uninterrupted flow of material Constant head of material Constant paving speed Set feeder system at a constant rate

5 Material Consistency 5 Remixing occurs when augers bring material in to the conveyor Remixing occurs when material is conveyed to the hopper Remixing discharge hopper

6 Production 6 Match paving rate to plant output Improves trucking efficiency

7 Production Lower Haul Costs 7 When using a 20-ton truck and the paving rate is 300 tons/hr Windrow takes 30 seconds to lay End dump takes 3-4 minutes to empty

8 Production Improved Trucking Efficiency 8 Truck interchange inefficiencies can be eliminated Decreases truck grouping

9 Low Wheel Loads 9 Wheel loads do not exceed agency guidelines Low ground contact pressure Smaller physical dimensions than MTV

10 Material Management 10 Project Planning Windrow Placement Paver Speed Trump Dump Intervals Dynamics of a Windrow

11 Project Planning 11 Roadway is used as surge device Material placement and windrow size are important Windrow size must mirror paving conditions

12 Windrow Placement 12 Combining augers allow use of various types of windrow placement Belly Dumps Live Bottom End Dumps

13 Truck Dump Intervals 13 Dump Zone Calculate the distance ahead of the paver based on mat width and depth Establish dump zone

14 Dynamics of a Windrow 14 Field measurements show temperature loss is minimal Only surface cooling takes place Internal temp remains constant Combing augers remix

15 Windrow Paving Operations 15 Machine Setup Paving Tips

16 Paver/Elevator Attachment 16 Place on level surface Attach mounting bracket to paver Raise or lower elevator so mounting bracket and paver match

17 Scraper Adjustment Scrapers adjust with a ratchet (1) Center scraper height adjusts with leg cylinders (2) Adjust center scraper if center streaks occur behind mat

18 Paving Tips Hopper Capacity and Speed 18 Adjust truck dumping to match paving speed Never get more than 2 truck loads ahead Use second truck to dump on existing windrow if hopper is low Leave gaps if hopper is full

19 Paving Tips Windrow Placement 19 Windrow should be centered Due to wide width, windrow can be off-centered to meet operating conditions If angle of grade fills hopper uneven, move windrow to opposite side

20 Paving Tips Moving into the Windrow 20 Adjust legs to pick up material from surface Adjust outside scrapers to pick up material behind augers Pick up enough material to fill hopper Back up paver, set up screed and start paving

21 Paving Tips Trucking 21 Closely monitor dumping procedures or have loader on site until crew becomes proficient with placement

22 Machine Features 22 Three-point suspension Material feed system Material conveyor system Dual operator stations Adjustable scrapers Remixing discharge hopper

23 Summary Windrow Paving Advantages 23 Uniform flow of material Minimal thermal segregation Trucking efficiencies Lower machine operating costs Low ground pressure Simple machine transport

24 4 Thanks for your Participation Please complete the evaluation to provide your feedback on this session and suggest topics for future events. Remember to mark these upcoming events on your calendar! March 7-11,