THE NEW KEENE ROCK crushers AND COMBINATION ROLLER MILL
Keene Engineering has brought into view, a new rock crusher that has brought the mining industry to its feet. A new combination rock crusher and roller mill that has the capacity of crushing a four by six rock into “ultra fine powder,” in one single, quick and efficient operation. They have combined two separate processes of rock crushing into a single machine.
The first stage is a jaw crusher that crushes aggregate to one quarter of an inch, that can be adjustable to larger or smaller size and the second stage is an adjustable roller mill that further reduces the grind to a fine powder.
No, this unit doesn’t cost ten thousand dollars, that might be considered a competitive price on the market today. THE COST IS LESS THAN HALF.
When AU Testing Laboratories first agreed to make an evaluation on this product, we were needless to say skeptical about the manufacturer’s claims, but were again impressed with the performance of this beauty. We learned that Keene had been in the process of engineering and testing this unit for over 10 years and this unit has evolved from some twenty previous prototypes.
We loaded the unit with its portable trailer on the back of our pick up and headed for an old mining area that had been abandoned several years ago due to low grade ore. We figured that this area would be a good testing site because it contained an abundance of fractured quartz rock containing gold and silver. The rock was also extremely harder than common type ore of this nature and should provide a good test for any type crushing equipment .
Although the unit weighed over 700 pounds it was surprisingly easy to tote around. We moved many times to different locations on the mine site with relative ease. We understood that this machine could be provided on either a permanent
base or trailer mounted. We chose the trailer mounted model, as it more adequately fit our needs for portability. Before we started our test run we noted that the crusher was really equipped with beefy appearing structure and heavy duty bearings, much larger than we have seen on similar size crushers.
The engine was the new eleven horse power. Honda industrial aluminum block with steel sleeve engine. We noted that the feed hopper was a safe arrangement to prevent rocks from being thrown back at the operator while running and the
belt shrouds were well designed for safety and could meet any mining safety requirements. The crushing jaws of this baby were heavy grade hardened steel and the roller mills were heavy duty and of the type that we have seen on much larger units. We threw everything we could find at this baby for over an hour, just to see what it would do in a given period of time. We were amazed at the rate it digested material.
We weighed the powder that we had processed in that one hour period and it was over “seventeen hundred pounds.” Although the manufacturer had rated the machine at a slightly higher capacity, the rock was extremely hard, we again were impressed with this performance. Like so many other machines on the market that we have tested, it was truly gratifying to find that the machine actually met the manufacturer’s ratings.
Reliable 11 HP Honda Engine
We continued to work the machine almost non stop for several days, examining the unit for any weakness in the bearings and any excessive play due to wear and tear and found very little that we could critique. We did make a couple of suggestions to the Keene’s regarding Chain Tensioner. It was bothersome making periodic adjustments every
few hours. We recommended an automatic tensioning device that would maintain proper tension. We also suggested that they should consider a device that would divert the crushed aggregate away from under the machine in order to make it convenient to remove the material. Keene was very receptive to our suggestions and we understand that these changes have already been put into production.
We questioned the absence of vertical grooves on the jaws that we have experienced with other brands. Keene said the sole purpose of the grooves were to relieve stress in cases where inadequate bearing size were present. He also replied that such grooves could slow down production capabilities and their flat plates provided more usable crushing
area and surface, thus making the jaw speed faster and more efficient.
Although we agree that the RC46 Rock Crusher is more efficient, faster, more portable than others we have used, the most important factor that is worthy of mention, is “DURABILITY.”
The RC46 has the components of jaw crushers , at twice its size,” by market comparison. Its 21 inch eccentric shaft is “one piece”, providing extra strength to hold the bearings and fly wheels from any possible misalignment. The bearings are the largest we have ever seen on this size crusher and are taper roller bearing that require minimum maintenance
and offer extremely long life.
Roller Mill and Heavy Structure
The rollers are fabricated with a 4340 alloy steel and treated to a Rockwell 50 Hardness, that offers an incredibly
long roller life. We experienced virtually no wear during the several days we worked this unit.
We again, have to credit the engineers at Keene with another superbly designed piece of equipment and another first in this industry. We also have to mention this smaller rock crusher that is designed primarily as a pilot mill and unlike the
RC46 is not a production machine. Material is fed into the hopper and drops into the center of a high speed tube. The centrifugal force throws rock into a hardened steel impact wall at speeds in excess of 400 MPH.
All material passes into a five gallon bucket sealed chamber It is a light weight and very economical rock crusher for the prospector, weighing only 85 lbs. It is mounted to a vertical 5 hp Briggs and Stratton and will handle rock of one inch in size and can produce up to 4000 lbs of grind in just one hour in a single pass.