Living in the snowy tundra, also known as the State of Minnesota, I am fully aware of the adversities that cold weather and snow can bring to everyday life. People and machines just do not move the way they do in the summer months. Keeping your people and equipment operational seems like an endless battle this time of the year. I have a couple of suggestions on how to limit the “frostbite” in your operations.
Let’s start with electronic system controls. These can have operational temperature range that will be exceeded in the cold season in many areas of the country. Some control cabinets that enclose timers, relays processors, racks & cards are equipped with heat strips to maintain minimum operating temps. Others just use the heat generated by items like power supplies to keep the cabinet warm. Checking heaters and the circulating fan (if equipped) to see if they are in good working order is the first step in reducing downtime. If your equipment does not have heat strips, the addition of a simple high wattage light bulb may be all it takes to heat up the cabinet to the desired temperature. Consult with your equipment manufacturer for the correct wiring. Generally wiring up to the 110 volt control circuit will work just fine. As always, make sure you keep the cabinet door closed.
Sensors, switches, and motors typically are rated for the harsh environments. Other than keeping these components clean and dry no other actions are required.
Cold weather can play havoc with most pneumatic systems. Moisture and lubricants (if used) tend to gum up valves, cylinders, and other actuators. Start by removing as much water vapor before it reaches the components using air dryers and filtration. Bleed and clean water traps on a regular basis. If lubricants are required by the manufacturer, make certain they are rated for your cold weather applications.
One of the most overlooked pneumatic components is the air muffler. Usually consisting of a fine sintered brass type material, they often collect debris and restrict air flow. Mounted at each valve or valve bank, air must exhaust freely. If not, clean or replace as required. I know there is a temptation to operate without mufflers installed, but they also stop debris from entering the air system from the outside. Short term testing is okay, but long term, make sure that mufflers are installed and working properly.
Problems can seemingly come out of no where in cold weather. For example, you look out and see your pallet system sitting idle first thing in the morning because the hydraulic fluid is too cold. Either the pumps won’t start because the minimum temperature has not been reached or it is running, but chains and cylinders are barely moving. Your staff responds either by disabling the low temperature sensors to get the pumps running or adding external heat. Disabling these sensors is not good for the machine. Instead, the solution is to set the tank heaters correctly so that the machine is warm by the time it is ready to go.
Setting up and maintaining the hydraulic tank heaters are critical this time of the year. In most cases, the heaters are controlled by time and temperature. Starting with time, the tank heaters should come on at least two hours before your start time. Most manufacturers want fluid temperature to be at about 100 degrees Fahrenheit before operation. The problem usually occurs when the timers are set in the late fall and not readjusted in mid winter to make sure the correct temperature is reached. Also in some cases I recommend that the heater time be set to run during the operational times of the system. This will help maintain temperature during the day. Temperature setting should be set to the desired operational fluid temperature.
A quick note on operator stations, if you use heaters, make sure they are far away from hydraulic hoses. I have heard too many horror stories that a fire occurs because a hose develops a leak under pressure and the fluid contacts a heater flame or element. The result can be catastrophic. As always, employees should use eye and hearing protection and make sure that their work areas are clean and dry.
The process of building a pallet with frozen decking and stringers creates some very interesting challenges. Splitting frozen boards can be reduced by using a blunt style nail. Also try moving the nail insertion point as far away from the edge as possible. Breaking apart frozen decking before placing them into automatic feeding hoppers will reduce jamming. Branding a frozen hardwood stringer can be problematic. Increasing contact time and brander temperature will help. Other suggestions include using a higher wattage heater elements, making sure head alignment is correct, and raising draft hoods up to lessen their cooling effect.
In the world of pallet assembly, each facet provides unique problems that can be reduced by simple planning and execution. Hopefully some of these tips will get you through the long, cold winter. Remember, spring will be here before you know it.
