Ligna Two Saw Carriage Scrag Top
Dogging
PURPOSE:
To saw logs from 6" to 16" diameter, 6' to 16' long
(nominal), by making two simultaneous cuts with two circular inserted tooth sawblades in a
single pass after positioning the log/cant and securing it onto a carriage bed by overhead
dogs. Additionally, this scrag is capable of returning a sawn cant back to the infeed
position for additional simultaneous cuts. If "four-sided" cants are required,
the initial sawn can be returned to the infeed position, "un-dogged", turned
with a flat side down on the carriage bed, re-dogged, and sawn again to produce the
"four-sided" cant.
PRINCIPLE OF OPERATION:
A log is loaded in the infeed position. The operator rotates
the log by engaging a reversible double set of turning rolls, which are raised to accept
the incoming log. Additionally, the operator can utilize three sets of
"centering" arms to assist in proper positioning. After obtaining the best
possible processing position, the operator lowers the rolls, which places the log/cant
onto the carriage bed. The operator engages the four overhead dog arms, which secure the
log/cant to the bed. The saw blades are set (by operator) and the carriage is advanced (by
operator) into two circular saws to accomplish the desired simultaneous cut. If resawing
is required, the operator can return the carriage and sawn cant to the infeed position,
reset the saws, and repeat the sawing function. (including release and redog for
"four-sided" sawing). The final sawn cant is offloaded (by operator) using an
overhead removal system onto a transfer, for further processing.
Slabs and/or cut pieces are removed from the saws by
off-bearing belts onto dropbelts, which direct the pieces to a waste processor (chipper)
if in a "down" position, or to a takeaway rollcase (included in outfeed section)
for additional processing. All of these functions are controlled by the operator.
GENERAL DESCRIPTION:
This scrag features integrated construction, with the infeed,
center and outfeed sections mounted a common frame consisting of 12" beam and 8"
beam crossmembers. A top-driven carriage traverses the entire assembly, and is reversible
for reloading and/or multiple pass sawing.
Infeed Section:
- 12" beam and 4" tubular construction
- Capacity - maximum opening of 18'0"
- Two sets of 8" diameter split log turning rolls, each 6'
long with steel bar welded around the circumference of each roll; mounted on 2-3/16"
shafts and bearings; powered hydraulically with #80 roller chain drive; raised and lowered
by hydraulic cylinders (by operator)
- Three sets of scissors type centering arms, made of 1"
thick steel plate; mounted at each end and between turning rolls on turning roll shafts;
positioned by hydraulic cylinders (by operator); used to assist positioning
Center Section:
Two husk assemblies, each featuring
- 12" beam and 4" tubular construction
- 2-15/16" mandrel with 8" saw collar
- 100 HP ODP 1800 RPM electric motor
- "5V" v-belt drive for 700 RPM
- NO SAWBLADES INCLUDED
- Above 100 HP motor and v-belt drive are designed for 48"
saw blades only
- NOTE: Larger saw diameters require larger motors and v-belt
drives
- 20" wide off-bearing belt with 2 HP electric drive
- Movement via linear bushings mounted on 2" hardened round
"WAYS"
- Standard setworks with MUDATA electronic push-button sets
(moving both saws equidistant); up to 12 sets included; hydraulic movement with one
cylinder, two racks and one common pinion
Outfeed Section:
- 12" beam and 4" tubular construction
- Two 22" wide, 12' long dropbelts, activated by air
cylinders, with 2 HP electric drive for each dropbelt
- Two 12' long takeaway rollcases, with 6" X 24" rolls
on 1-7/16" shafts and bearings, with one 2 HP electric drive for both rollcases;
extending to end of scrag frame (outfeed area)
- Cant offloading system, with overhead mounted "Sweep
Arm" assembly activated by air cylinders(s) (controlled by operator)
Carriage Section
- 2" X 8" tubular construction
- Bed includes angular steel log supports to provide stability
- Four overhead mounted "dog" arms of 1" thick
steel plate; positioned (up/down) by hydraulic cylinders (controlled by operator)
- Overhead cable carriage drive system, powered by hydraulic
motor; including cable drum and sheave; 5/8" wire cable; variable speed (3 FPM to 150
FPM - nominal)
- Carriage supported on angular trackway, traversing on steel
machined wheels, (controlled by operator)
Hydraulic System:
- 30 HP ODP 1800 RPM electric motor
- 30 GPM hydrostatic pump
- 80 gallon oil tank with filter; heater/cover; necessary
hardware
- Hard pipe and hose plumbing with fittings and controls
Operator's Cab:
- Nominal Size - 4'6" wide,6'0" deep, 7'0" high
- Front sloped wall with safety glass window
- Left/right walls with safety glass windows
- Door on rear wall, with safety glass window
- 1" sound suppression insulation
- Fluorescent light and receptacle
- Roof-mounted heater/air conditioner
- Operator's console with pedestal (starters not included)
OPTION:
Computerized setworks package for symmetric and non-symmetric positioning of saws
(individually) includes; one Temposonic transducer with two magnet sensors; one hydraulic
cylinder with two valves(for two-speed operation) for each saw; computer, monitor, switch
panel(s), cable set.
