The GRUB-3000 self propelled, radio control operated crushing and padding machines, are specially designed and manufactured for the pipeline industry. They are recommended to work with crushed stones as well as mixed material, directly on the ground in sizes of up to 16 inches (406 mm). They are equipped with a collector belt that removes the crushed material and conveys it to the rear, onto a second transverse conveyor belt that can unload the product, to the right or left hand side of the machine travel direction. This second conveyor belt can be moved in and out in order to discharge the material, exactly into the center of the trench, for bedding and padding, or out of the trench, as needed. The transverse conveyor belt can be easily removed for machines transportation purposes or to have the material fall to the ground, within the machines trail. They are equipped with a remote control that can easily operate the machines, from start to any working activity, offering the following advantages:
It allows the operator to control, while moving around the machines during the operation, supervising when the material is coming into the mouth of the machines, as well as when the material is coming out of the conveyor belt, for discharge, from a safe distance, and away from any sources of dust, noise and vibration. Crushing activity takes place in the mouth of the machines, by means of rotating hammers and a specially designed grid, formed by over- lapping bars that determine the maximum size of the material, making it clog proof, even in extremely damp conditions
Hourly production vary from 3000 to 4200 Cubic Feet ( 90 to 120 Cubic Meters) of fine product depending on the nature of the material to be crushed, and the conditions of the terrain.
Maximum production expected per lineal meter, in ideal conditions can be 55 Cubic Feet (1,5 Cubic Meters). When this maximum production is not required, the travel speed can be increased
Working speed during operation, can vary continuously from 0 to 0,4 miles per hour ( 0 to 650 Meters per hour); maximum travel speed can reach up to 1 miles per hour ( 1600 Meters per hour), depending on type of terrain and material specifications.
The grading curve of produced material, as in all cases of general crushing, depends on the two following factors:
Bar screen size that determines the maximum size of material. The hourly production rate, depends on larger or smaller size material.
Hardness and nature of rocks. With crumblier material, a higher percentage of fine material can be obtained.
On the contrary, an increase in compressive strength will increase the percentage of coarse grains closer to the maximum size. The nature of crystals and their arrangement, also affect the grading curve of the crushed material.
The hammers are manufactured with special wear-proof material, and the length of service life depends on the type of rock to be crushed, as well as the percentage of moisture contained in the material. A higher silicon content in the material composition, and a higher content of moisture, will decrease the hammers service life length.
Our working experience in various conditions, shows that with calcareous stones of medium hardness (weight of accumulated material from 1,76 up to 1,87 tons per cubic yards, equal to to 1600/1700 Cubic Meters), the life of the hammers exceeds 200 hours in dry conditions. With granites the average life of the hammers ranges from 20 up to 50 hours.
Using the GRUB-3000 Crushing and Padding machines, has proof to be economically advantageous in all cases, where it wouId be necessary to collect and transfer fine padding material, from areas surrounding the construction site.
These machines are mounted on high type tracks, and equipped with Caterpillar diesel engines, model 3412E, offering 750 HP @ 2000 RPM; hydrostatic transmissions and variable displacement pumps.
