hydraulic monitor[hī′drȯ·lik ′män·əd·ər]
an apparatus for creating and controlling powerful water jets capable of dislodging and washing out rock formations, ash, and slag. Hydraulic monitors are most widespread in construction and in open-pit and underground working of mineral deposits.
Hydraulic monitors were first used in Russia for mining gold in the Urals (1830); later (1880), K. F. Pen’evskii used hydraulic monitors made of canvas tubing and designed to operate under a pressure of 0.6-0.9 meganewtons per sq m (6-9 kilograms-force per sq cm) for washing out peat on the Nygri River.
A hydraulic monitor (see Figure 1) consists of a lower, stationary elbow joint and an upper elbow joint, which can rotate around a vertical axis because of a swivel apparatus. The barrel of the monitor can be inclined upward and downward from the horizontal by means of a ball joint. Water is supplied under pressure through a pipeline from a pumping station to the hydraulic monitor and, through a system of joints and hinges, enters the barrel, which has an angle of taper of 3°-5° in the direction of flow. The barrel ends in a nozzle, where the water jet is formed. The rock washed out by the jet is transported in the form of hydraulic fill either by gravity flow or by means of dredges.
Hydraulic monitors are distinguished according to purpose—for open-pit operations, underground operations (see Figure 2), and special purposes; according to technological criteria—cutting and washing types; according to the pressure created—high- and low-pressure types; according to the method of control—manually and remote-controlled; and according to the positioning at the mine face—those that operate directly at the face (close-action hydraulic monitors) and those that operate outside of the cave-in contour of the terrace (bench).
The technical development in hydraulic monitor construction is proceeding primarily in the direction of creating self-propelled hydraulic monitors operated by remote control.
REFERENCETsiapko, N. F., and A. M. Chapka. Gidrootboika uglia na podzemnykh rabotakh. Moscow, 1960.
Nurok, G. A. Gidromekhanizatsiia otkrytykh razrabotok. Moscow, 1970.
V. I. SHELOGANOV