180 likes | 1.47k Views
INTRODUCTION CABLE YARDING OPERATIONS HIGHLEAD, LIVE SKYLINE, RUNNING SKYLINE DEMONSTRATION/CONTEST. Cable Logging, Equipment & Systems. FOR 420 Feb 1, 2001 James Hart. CABLE YARDING.
E N D
INTRODUCTION CABLE YARDING OPERATIONS HIGHLEAD, LIVE SKYLINE, RUNNING SKYLINE DEMONSTRATION/CONTEST Cable Logging, Equipment & Systems FOR 420Feb 1, 2001James Hart
CABLE YARDING • CABLE YARDING - MOVEMENT OF LOGS FROM STUMP SITE TO LANDING USING A MACHINE EQUIPPED WITH MULTIPLE DRUMS (OR WINCHES) OPERATED FROM STATIONALRY POSITIONS IN THE LANDINGS. • FIRST STEAM DONKEY (SMALL YARDER WITH A VERTICAL BOILER) WAS INVENTED ~1881 BY JOHN DOLBEER TO GROUND SKID LOGS IN OREGON • FIRST SKYLINE CABLE SYSTEM USED IN MICHIGAN ~ 1886 BY HORACE BUTTLER. • SYSTEMS STILL IN USE OLD PNW YARDER
BASIC CABLE YARDING SYSTEM COMPONENTS • YARDER - TYPICALLY A RECTANGULAR FRAME BUILT FROM I BEAMS, WITH ENGINE AND DRUMS • TOWER, WITH GUY LINES • WIRE ROPE 6 STRANDS OF 19 WIRES EACH • MAIN LINE 1-1.25” -- HAULBACK LINE 3/4-7/8” • SKYLINE 1.5-2” -- OTHER MISC. • BLOCKS - PULLEYS • CKOKER - SHORT FLEXIBLE WIRE ROPE • BUTT RIGGING - COMBINATION OF CHAINLINKS, CLEVISES, AND SWIVELS CONNECTING • MAIN HAUL LINE • CHOKER OR GRAPPLE, AND • HAUL-BACK LINES • CARRAGE - COMBINATION OF PULLEYS, CABLE, ETC. THAT RIDE ON SKYLINE, ARE PULLED BY MAINLINE AND MAYBE A HAUL-BACK LINE, HAVE CHOKERS OR A GRAPPLE; AND PERHAPS A SLACKLINE
HIGHLEAD SYSTEM • CLEARCUTS • CONSTANT SLOPES • 30-70% SLOPES, 1000’ DISTANCES • UPHILL YARDING • 2 DRUM YARDERS • DRUM -- MAINLINE -- BUTT RIGGING (with CHOKERS/GRAPPLE) -- HAUL-BACK LINE (with BLOCKS) -- DRUM • 20 LOGS/DAY
HIGHLEAD SYSTEM [CONT] SKAGIT 3-DRUM PORTABLE TOWER WITH GUY LINES CABLE LOGGED CORRIDOR IN PNW
LIVE SKYLINE SYSTEM • SKYLINE LIFTS LOGS • LIVE SKYLINE MOVES UP/DOWN TO GET CARRAGE TO LOGS • 2-DRUM YARDER IS ELEVATED, USES GRAVITY AND NO HAUL-BACK LINE • 30-90% SLOPES, 500-4000’ • DRUM -- SKYLINE --ANCHOR (or TAIL-SPAR TOWER) • DRUM -- MAINLINE -- CARRAGE (with CHOKERS OR GRAPPLE) • ELEVATED OPERATION • ALLOWS PARTIAL CUTS • DECREASES DISTURBANCE • 470 LOGS/DAY
RUNNING SKYLINE SYSTEM • 3rd DRUM FOR HAULBACK LINE • DRUM -- SKYLINE --ANCHOR (or TAIL-SPAR TOWER) • DRUM -- MAINLINE -- CARRAGE (with CHOKERS OR GRAPPLE) - HAUL-BACK - DRUM • ELEVATED SKYLINE • ALLOWS PARTIAL CUTS • DECREASES DISTURBANCE • UPHILL OPERATION • 4th-DRUM CAN ADD SLACK-PULLER TO LOWER/RAISE CABLE AND KEEP SKYLINE STATIC • 30-90% SLOPES, 500-4000’ SLACK-PULLER CARRAGE
can yard logs over ground on which tractors cannot operate Running skylines operate in any direction up-slope down-slope operate in any weather less damaging to soil than tractor skidding operates faster than tractor on same terrain limited primarily by the line capacities of the yarder drums the high-lead is used for only clear-cut the cost of moving, and changing yarding road are fixed, not efficient for low volumes of harvesting High costs per unit for low values per acre discriminates against small log operations CABLE LOGGING SYSTEMS------------------------------------------ ADVANTAGES DISADVANTAGES