garyhlucas
Stainless
- Joined
- Oct 17, 2013
- Location
- New Jersey
I have posted about my grandson working with me at my job and we are getting ready to start on a new project. The company purchased a 2 axis drilling machine with 5 spindles to drill 104 holes in polypropylene header pipe. It was here when I arrived and they asked me to get it up and running after another engineer had installed guards and such. It is a Chinese machine and basically junk made from scrap metal. However I did manage to get it to do a beautiful job and I cut the cycle time from almost 3 minutes to 1 minute flat. Because it was running at 3 minutes they had already ordered a second machine, double sided with 16 spindles! That is the one we are taking a whack at now.
I thought I'd write about it because I think I have figured out a way to automate it, eliminating 2 operators per shift over 2 or 3 shifts. We extrude our own pipe and the pipe must sit for 24 hours between being extruded and cut to length before drilling because the material spirals a bit as it crystallizes. So the pipes must be stored in large racks. So I felt the key to automating this process was finding a way to automate unloading the racks, and possibly loading them automatically.
What I came up with is two flat straps across the rack and under the pipes attached to an unloader that sits on top of the rack. A shaft on one side with slots for the straps like tie down straps is turned by a gear motor that rolls the straps up. So the whole 1000 lbs of pipes rise in the rack and flow over the fixed side and down a ramp into the machine. An eye senses the ramp is going empty and turns on the lift motor and it goes off when the ramp refills. There are two sets of clamps that are parallel for drilling. So the ramp leads to a shaft with slotted disks. Pipes fall in the slot and the disk rotates left or right and rolls the pipe into the loading station.
The pipes are sitting in the loading station on the left. I've added a gripper to both ends of the Z axis each with an air slide to drop them below the spindles. Th Z axis picks up the pipe in the load station with the left gripper and the finished pipe in the right gripper and travels to the right end of the machine. It puts the new pipe in the clamps and drops the finished pipe into one of the 6 carts my grandson just finished building. Then the machine drills its way back to the starting position using the 16 spindles.
We are fabricating the rack unloader right now. We have lots of racks already. The key is getting the rack unloaded, if that works everything else is fairly simple. No CNC controller, using a PLC that can handle the 3 axis motions, and 8 sets of air operated drilling clamps and the HMI. A second identical PLC on the Y axis carriage handles about a dozen sensors and limit switches along with 12 air valves. Only a 24vdc power cable and an Ethernet cable connect the two PLCs.
If this works out we will be building a second machine. This machine will be a lathe that picks the pipe off the extruder line again with a linear axis and double grippers. The new pipe gets placed on the expanding arbor by the first gripper and the finished pipe is picked and dropped into a vertical conveyor that drops it in the racks that feed the drill machine! You can't just drop pipe 5 feet into an empty rack. So the straps in the rack will be wound up tight and as the pile builds the straps will slack off lowering the whole bundle to the bottom. When the pile starts rising above the rack, it's full and the operation stops. A gate on the extruder lets it keep making pipe and dropping them into a manual bin for a short time.
The lathe does 3 operations on 4 lengths of pipe. So it has two servo operated 2 axis carriages. One by the chuck grooves the pipe and chamfers the end. The other end of the lathe has an expanding chuck on the tailstock. A second carriage grooves that end, trims the length, and chamfers it. The tailstock and both carriages run on the same linear rails. So the program moves the tailstock and second carriage as needed for the different pipe lengths. This lathe eliminates two more operators.
If you think we are getting rid of lots of employees, it is actually a small number, because our process is REALLY labor intensive and lots of jobs require thinking and sensing and handling that simply can't be done by robots or machines as the solar collectors we build are floppy and vary in size from 2' x 4' to 4' x 20'
I'll post some photos if people are interested.
I thought I'd write about it because I think I have figured out a way to automate it, eliminating 2 operators per shift over 2 or 3 shifts. We extrude our own pipe and the pipe must sit for 24 hours between being extruded and cut to length before drilling because the material spirals a bit as it crystallizes. So the pipes must be stored in large racks. So I felt the key to automating this process was finding a way to automate unloading the racks, and possibly loading them automatically.
What I came up with is two flat straps across the rack and under the pipes attached to an unloader that sits on top of the rack. A shaft on one side with slots for the straps like tie down straps is turned by a gear motor that rolls the straps up. So the whole 1000 lbs of pipes rise in the rack and flow over the fixed side and down a ramp into the machine. An eye senses the ramp is going empty and turns on the lift motor and it goes off when the ramp refills. There are two sets of clamps that are parallel for drilling. So the ramp leads to a shaft with slotted disks. Pipes fall in the slot and the disk rotates left or right and rolls the pipe into the loading station.
The pipes are sitting in the loading station on the left. I've added a gripper to both ends of the Z axis each with an air slide to drop them below the spindles. Th Z axis picks up the pipe in the load station with the left gripper and the finished pipe in the right gripper and travels to the right end of the machine. It puts the new pipe in the clamps and drops the finished pipe into one of the 6 carts my grandson just finished building. Then the machine drills its way back to the starting position using the 16 spindles.
We are fabricating the rack unloader right now. We have lots of racks already. The key is getting the rack unloaded, if that works everything else is fairly simple. No CNC controller, using a PLC that can handle the 3 axis motions, and 8 sets of air operated drilling clamps and the HMI. A second identical PLC on the Y axis carriage handles about a dozen sensors and limit switches along with 12 air valves. Only a 24vdc power cable and an Ethernet cable connect the two PLCs.
If this works out we will be building a second machine. This machine will be a lathe that picks the pipe off the extruder line again with a linear axis and double grippers. The new pipe gets placed on the expanding arbor by the first gripper and the finished pipe is picked and dropped into a vertical conveyor that drops it in the racks that feed the drill machine! You can't just drop pipe 5 feet into an empty rack. So the straps in the rack will be wound up tight and as the pile builds the straps will slack off lowering the whole bundle to the bottom. When the pile starts rising above the rack, it's full and the operation stops. A gate on the extruder lets it keep making pipe and dropping them into a manual bin for a short time.
The lathe does 3 operations on 4 lengths of pipe. So it has two servo operated 2 axis carriages. One by the chuck grooves the pipe and chamfers the end. The other end of the lathe has an expanding chuck on the tailstock. A second carriage grooves that end, trims the length, and chamfers it. The tailstock and both carriages run on the same linear rails. So the program moves the tailstock and second carriage as needed for the different pipe lengths. This lathe eliminates two more operators.
If you think we are getting rid of lots of employees, it is actually a small number, because our process is REALLY labor intensive and lots of jobs require thinking and sensing and handling that simply can't be done by robots or machines as the solar collectors we build are floppy and vary in size from 2' x 4' to 4' x 20'
I'll post some photos if people are interested.