Over the last 20 years, the Gillingham-Best engineering team has made continual improvement in the design of lumber stacker systems.
By analyzing more than 60 of their own installed and operational stacker systems, and those of the competition, the team has optimized their designs to eliminate failures caused by overly complex operations.
The culmination of the extensive R&D and field experience is the Variable Pan GeometryTM System.
For the VPGTM System, Gillingham-Best has simplified and upgraded its design to achieve maximum performance and uptime.
VPGTM System Benefits
Eliminates costly bent stick lifting arms
Simplifies machine operation & timing
Allows safer, single user operation
Provides perfect stick alignment
Features variable inset from end of package
Operates smoothly and quietly
Runs with wide range of sticker quality
The Industry's Performance Leader
Gillingham-Bestís VPGTM lumber stacker systems are designed for 24x7x365 uptime.
To eliminate the operator safety problems and mechanical breakdowns encountered in competing systems, Gillingham-Best avoided using any sticker lifting components.
The sticks are transferred from the distribution chain to pans on to the stacker forks.
As they arrive, the pans pivot down to receive the sticks.
The pans are operated by a single hydraulic cylinder.
A common connecting bar is attached to a bell crank at each pan location.
By minizing mechanical and hyrdraulic components, uptime is improved, mainenance is reduced, and return on investment is maximized.
Field reports from existing stacker installations show almost no down time from sticker jams.
Operators have reported full shifts without a single sticker jam.
Cold weather is not a concern with Gillingham-Best's stackers.
In northern Idaho, a Gillingham-Best lumber stacker runs out in the open with only a roof.
Operating temperatures have been below 0 degrees F.
Frozen lumber and stickers are easily accomodated by the system.
VPGTM System Features
12" sticker placing for hardwood mills
Stacker cycle speeds up to 15 courses per minute
Two speed hoist valving for smooth indexing & fast return
Hoist track and carriage tracks are replaceable T-1 steel
Chain C2080 standard
Structural tube steel framing
Course widths 36" to 96"
Package weight 5,000 lbs to 150,000 lbs
Course weight 300 lbs to 3,600 lbs
Programmable logic controller selects proper sticks for selected lumber length
Random width options
Proximity type sensing switches
Standard off-the-shelf components
Advanced MMI Screen controls
Eithernet communication with all devices
The key to minimal maintenance on the VPGTM system is the use of 11 heavy duty pivoting pans and one hydraulic cylinder and valve to place the stickers into the package.
In comparison, the typical overhead magazine system uses 33 air cylinders, air valves, and mechanical mechanisms for the same task.
The magazines require almost constant maintenance, while no scheduled maintenance is required on the Gillingham-Best pan system.
Gillingham-Best's mature design has evolved over many years, with experience leading to improvements in all areas of the stacker.
Gearboxes used are Cone Drive with double involute worm gears. These boxes are good for many millions of cycles or years of service.
Every cam roller in the stacker rides on T-1 steel.
The package hoisting chains are designed with a safety factor of 5 times.
No proportional or servo valves are used. No temposonic cylinders are needed.
Even though the stick system is built into the stacker, the stacker has the motion of a high speed package maker type system.
The stick system changes advance and speed based on the length of lumber. Only the minimum advance is used for a given length of lumber.
The stacker system has three speeds. The operator can use the optimal speed required for the flow. Reduced speed and motion prolong the life of all components.
The control system contains hidden jog screens to help maintenance personnel troubleshoot.
Hidden timing screens are also available to fine tune the stacker.
Modems and VPN connections allow online support from GBI.
A complete and thorough maintenance manual is provided in CD format.
Most replacement parts can be procured from local sources.
Gillingham-Best's VPGTM system uses a 10" x10" color touchscreen panel for its operator interface.
The main screen provides the operator with the current status of all stacker sub-systems.
This is done with a grid of green blocks.
If any block is red, the operator can immediately identify the item that is preventing the stacker from cycling.
The control system also monitors all motor starters.
If a starter trips, the operator receives a warning on the screen.
Internal diagnostics are available for all stacker functions.
The control system has evolved over many years and many stacker installations.
When compared to other manufacturers' systems, Gillingham-Best's current system has a more intuitive interface resulting in shorter personnel training times.