[ Home | Contents | Search | Post | Reply | Next | Previous | Up ]
From: David Roper (droper@thinkerf.com)
Categories: Circular Saw Guides & Lub.
Date: 10/26/98
Time: 3:11:41 PM
Remote Name: 209.153.197.94
Ken,
Saw Guide Lubrication systems have two jobs to do. They have to be able to provide lubrication to combat friction between the guide surface and the saw, and provide a coolant to overcome the heat generated during the actual sawing process.
Water itself is a good heat sink and as such does most of the work to overcome the heat generated during sawing. Water, however, is a poor lubricant and to combat the friction between the guides and the saws, a tacky type oil should be used which does not wash off easily. The volume used of this oil should be low so that there is no oil build up on the saws which will in turn cause heat.
Generally the volumes for a typical circular saw application of say a 22” diameter guided saw would be in the region of 0.125 - 0.200 gallons per saw per minute of a mixture of air oil and water. The mixture would take place in a venturi type mixing chamber and then sent directly to the individual guides, or to the guide stack. Generally, the oil would be of a tacky type with a viscosity suitable for different ambient temperatures. The volumes per saw for this oil should be around one gallon per shift per saw. These volumes would be increased or decreased by the diameter of the saw and the size of the saw guide. Generally it is determined by trial and error. Look for burn marks on the saw in the guided area for excessive guide friction, and look for gullet burn marks for excessive heating caused by the actual sawing process. The volumes indicated are relevant for most North American softwoods, for hardwoods, there may be an increase needed due to the close grain structure of the species.
The main problem with the conventional type of saw guide lubrication systems is their inability to detect a plugged system, or one that has leaks in it. To overcome these problems, TKT has designed a system that senses when the operating system pressure drops off or increases above or below a safe pre determined operating pressure. If the pressure drops off due to a broken line, or increases due to a plugged line, an alarm is tripped which warns the operator, and simultaneously operates a separate remote flood spray system as a temporary measure until the problem can be properly addressed.
Dave