Log Hauling Flashcards
What is a typical pulpwood hauling trucks capacity?
Around 18000 lbs
What does tandem axle refer to?
- 2 powered rear axles
- steel pole (stinger) connects trailer to truck
What does L75 refer to?
Vehicle plus load equals 75 tonnes
What are cheese blocks?
Wedge that keeps logs from rolling out of truck bed
What is the standard for wrapping loads?
2 wraps
Logs can only extend half diameter above stake for highway hauling.
Why don’t tandem trucks drag empty trailers behind them?
They put the trailer on top because the suspension is designed for heavy loads, making it a very bumpy ride.
What are 2 types of trailer?
Pole trailer (swivel)
Semi trailer ( no swivel )
What’s a jeep logger?
Combination of pole and semi trailer where an extra axle distributes weight more evenly.
Tridem pole trailer?
Same as jeep logger but 3 axles on rear trailer
What’s most common on the coast?
Tandem tandem pole trailer
Factors effecting haul time ***
- Road grade
- road surface
- super elevation ( corners banked to allow truck to maintain speed )
- sight distance (how far can trucker see)
- road width
- road alignment ( number of curves)
- ratio of horsepower to GVW
- delay times ( turnout spacing, loading waits, fuel line up )
How does turnout spacing effect empty trucks
The closer together they are, the more confident a driver can be that he will have space to pull over if he runs into oncoming. Loaded trucks never pull over.
At which slope do trucks travel fastest?
2%
What is FERIC
• Forest Engineering Research Institute of Canada
What were the FERIC findings?
- Loading time is a function of piece size
-large wood is much faster to load than small wood - Travel time of different truck types over the same section of road didn’t change much with load size
- Road standard has a large impact on travel time. Speed drops as road standard decreases
- Large variability in travel time was estimated due to
poor road conditions (periodic road maintenance)
drivers slowing down because they are aware of a delays at landing
Waiting in queue or waiting for the loader to do some housekeeping - Greatest wait at landing (waiting in queue or waiting on loader)
- Under this study conditions trucks with 10 foot bunks were the least cost
How does cost effect the owner operator?
- costs of operation like purchase price, fuel and maintenance are out of owners control.
- operators who replace vehicles at the right time come out on the winning side because repairs, downtime are more frequent in old trucks.
How can delays be reduced?
- Good dispatching
- correct number of trucks running
- load to capacity on each trip
- improve roads to increase truck speed and reduce maintenence.
- recognize trade off between road costs and trucking costs.
Cost estimating methods?
Otto: computer program that calculates costs.
When did trucks become popular?
1918
At which % does work safe require a risk assessment?
Anything above 18%
What is the engine retarder?
A valve that allows the engine to slow down a truck.
When are service brakes most important ? Why?
- above 18% engine brakes are useless and service brakes are needed more often.
What is brake fade?
Drum expands with increased temperature, can lead to failure.
Using water to cool brakes and tightening slack adjuster nut can help.
What are the key parameters when trucks are coming down steep grades?
- Length of grade – long stretches of steeper grades generate heat
- Steepness of Grade – steeper is worse – duh!
- Traction Conditions – Ice and Snow the limit is 13% (can’t stop above this) Smooth compact Gravel
