The tour began at the Advanced Manufacturing Technology Center in Mansfield, Texas. From the front it looks like any building one might see in an office park. But at the back of the building is a highly automated factory, where tools such as pliers and wire cutters are machined, assembled, and polished.
Pieces arrive at the factory as forgings; these were produced at a Klein facility in Elk Grove Village, Illinois. What you’re seeing are pieces of steel at various points in the forging process. The bars on the left were cut from 20-foot steel billets, heated, and forged (hammered between a series of dies) into the lineman’s plier parts at the right end of the table. Look closely and you’ll see that individual parts are knocked out of larger pieces of steel.
This 1990s era mechanical machining center came from the company’s old plant in Skokie, Illinois and serves as backup for a more modern device. Known simply as the “Green Machine”, it was top-of-the-line technology when new. Its claim to fame was that it could perform multiple operations without re-clamping the piece. The more times you reposition a piece during machining the more chances there are to introduce error.
Behind the blue tarp is the super-secret automated machining center that replaced the Green Machine. The tour guide indicated that if I were to sneak a peek he’d have to kill me. He didn’t actually say that, but I could tell that’s what he was thinking—so I decided not to chance it.
Here’s a shot of forgings being fed into the super-secret automated machining center. They come out the other end machined and ready for assembly. What happens while they are in there is anyone’s guess, though it’s reasonable to assume they are clamped a minimal number of times (maybe only once) and undergo multiple machining operations after.
Here is what the pieces for lineman’s pliers look like after machining but before assembly. Look closely and you’ll see cross-hatching on the jaw face, the hole for the rivet, and the beveled edge of the wire cutter.
This is an optical comparer; it’s used to inspect pieces after they are machined. It’s basically, a giant magnifier. The image on the screen is a close-up of the lineman’s pliers part clamped below.
While much of the work done in this factory is performed by automated machines, some tasks are best performed by humans. Here a worker smooths a part of a piece the machine couldn't get ( click here for video ).
This sample board shows long-nose pliers at various states of finish. The piece on the top left is a raw forging as it enters the plant. From there it goes through various machining operations, heat treating, assembly, and polishing. The pliers on the bottom right are ready to received dipped or molded handles.
Here is what long-nose pliers look like just after riveting. The rivets will be ground flush and the shape of the nose refined in an upcoming grinding operation.
Combination Pliers (long-nose with wire strippers) are one of Klein's newest products. Here they are after riveting and complete.
This is the inside of Klein’s newest facility, the recently opened heat treating plant in Mansfield, Texas. Heat treating involves hardening and annealing metal so it possesses the desired combination of hardness and toughness.
This sign is on a natural gas furnace that regularly goes to 1,600 degrees. I don’t imagine you’d have to touch it more than once to learn it would be a bad idea to touch it again.
Machined parts enter the facility in plastic bins and are placed into individual slots in metal "baskets" prior to heat treating ( click here for video ). This insures every piece is exposed to the same amount of heat—which would not occur if they were dumped into the furnace in a pile.
At various points in the heat treating process baskets of parts are run through what is essentially an industrial size dishwasher. The parts are washed in water and detergent to remove contaminants that might react with tool parts when they are in the furnace. What you’re seeing is steam coming out of the open door.
This is a hardening furnace. After baskets of tool parts are placed inside the door is closed and the interior heated to something approaching 1,600 degrees—at which point the parts are quenched (cooled) by lowering them into an oil bath. Rapid cooling hardens the metal by changing its structure and chemistry. The next step is to anneal the parts by putting them in a furnace, heating them to a particular temperature, and then allowing them to cool slowly over a period of time. This brings the metal to a specified level of hardness, so pieces are hard but not brittle.
This is not something you would normally see in the heat treating plant. The plant manager performed a burn-off, to intentionally create flames for a photo op ( click here for video ). Fortunately, nothing blew up or caught on fire—otherwise, I might not have been here to write this story.
This is what it’s like to look inside a 1,600 degree furnace. I shot this from 30 feet back and off to one side and yet I could still feel the radiated heat.
You’ve probably heard of the Rockwell Scale, a measure of the hardness of metal. Well, here’s a machine that can measure it. It presses the point of a diamond cone into the metal and measures how deep it goes. Klein uses this device and equipment in a nearby metallurgy lab to verify that parts have the specified qualities.
These pliers have been assembled and are undergoing selective hardening of the cutting edges. The edges are heated by induction—a non-contact method of electro-magnetic heating. When the edges reach a specified temperature they are quenched by dropping the tool into the liquid below. This leaves the edges harder than the rest of the tool. A similar operation is performed on the jaw faces of gripping tools such as pliers ( click here for video).
A pair of long-nose pliers is being manipulated by a computer-controlled robot capable of picking up tools and grinding them to shape with various grits of abrasive belt ( click here for video).
These long-nose pliers have been heat-treated, assembled, ground, etched, and polished. All that remains is to dip the handles.
I don’t think this picture would normally be there; it was placed in the assembly area for wire strippers so the people touring the plant would know what they were looking at.
Look closely and you will see the springs used in Klein’s wire strippers. They’re being spun in a drum to orient them so they can be fed into an insertion machine.
These folks are doing the final assembly and adjustment of wire strippers—tasks people can do better than robots (click here for video ).
These finished wire strippers have been boxed and will be shipped to the company’s packaging plant in Cedar Rapids, Iowa. Klein will eventually build a packaging plant in Mansfield so tools can be packaged close to where they are made.
After being hung from a rack and heated in a nearby furnace, diagonal pliers are dipped into liquid vinyl to form plastic handles ( click here for video ).
Different tools have different color handles—which makes it easy for tradesmen to know which tool they are grabbing out of their pouch.
Klein recently introduced a new line of insulated pliers rated to 1,000 volts. This production worker is testing a batch of them by lowering them into a tank of water and running 10,000 volts through it ( click here for video ). A buzzer will sound and a light will come on if any handles leak.
This gal cleans and inspects tools before they are sent out for packaging. In response to a question from one of the folks on the tour she’s showing off her Texas-style steel-toe work boots.
This is the heat-treating plant on the day of its grand opening. You can’t tell from here, but it’s big—by my estimate 250 feet wide by 200 feet deep (50,000 square feet). The building where tools are machined and assembled (The Advanced Manufacturing Technology Center) is by my estimate about 125,000 square feet.
These folks are from the Klein family—which has owned the company since its founding in 1857. They are practicing for the ribbon-cutting ceremony that is about to take place. What do you think they are going to cut and what will they cut it with?