All URB 2,5А drilling rig mechanisms are actuated by diesel engine via transfer box and gearbox being at 5th (direct) gear.
Drawing 2 – Kinematic Diagram
1-8, 10 – pinion gears; 9 – gear-shaft; 11 - single-thread worm; 12 – worm wheel; 13-18 – sprockets; 19-21 – gear clutches; 22, 23 – friction clutches; 24-27 - pulleys; А - KAMAZ-740 engine, В - power takeoff attachment; Е – feed unit transmission
Power takeoff is realized by means of special Power Takeoff Attachment (PTA) installed on the top hatch of transfer box. Electropneumatic Control of PTA is realized via selector installed on the control panel in the cab. Cardan shaft No.1 transmits rotation to the line shaft which includes 2 takeoff pulleys for pump and feed unit transmission. The line shaft joints with N gearbox by means of cardan shaft No. VI.
Three-speed two-shaft gearbox: pinion gear (number of teeth z=17) and pinion gear assemblies of 2nd and 3rd gear (number of teeth z = 34 and z =27) move along main driveshaft splines. There are cylindrical pinion gears No. 4 (z = 51), No. 5 (z = 34), No. 6 (z=41) h and bevel pinion No. 7 (z = 18) tightly installed on the driven shaft.
On the driven shaft end there is a gear clutch (21) activating rotor drive shaft.
Junction of pinion gear No.1 with pinion gear No.4 forms the first gear of ratio i = 0.33. Junction of pinion gear No.3 (z=27) and pinion gear No.6 forms the second gear of ratio i = 0.658. Junction of pinion No.2 (Z=34) and pinion No.5 forms the third gear of ratio i = 1.
Bevel pinions No.7 (z=18) and No. 8 (z=38) are tightly mounted on shafts; they create bevel drive of the ratio i= 0,474; the function is power takeoff for drawworks.
On the end there is a free sprocket No.13 (z=17) connected with sprocket No.14 (z = 70) installed on the drawworks drive shaft; drive ratio is i=0.243. Chain gear is activated by gear clutch No.20. On У drawworks shaft (on ball-bearings) there are two drums with installed friction clutches 23.
Rotary drive is actuated from gearbox shaft via cardan shaft VII connected with gear-shaft No.9 (z= 15)
Ratio of rotary gear set is i = 0,25.
The rotation is transmitted to the feed unit drive from the line shaft via V-belt drive which is formed by 26 and 27 pulleys. Pulley No.26 is constantly on.
Pulley No.27 is tightly mounted onto the shaft. Feed unit drive shaft No.VIII is actuated by friction clutch No. 22 and connected with worm reduction gearbox equipped with single-thread worm (11) and worm wheel No.12 (z = 30). On the worm wheel shaft there is sprocket No.15 (z=15) connected with sprocket No.16 (z=40); the sprocket No.16 is on countershaft of the chain gear. The same countershaft is equipped with sprocket No. 17 (z=20) connected with sprocket No.18 (z=40) by means of chain; the sprocket No.18 is mounted on feed unit shaft No.III.
The mud pump is actuated via V-belt drive by gear clutch (19) built in pulley (24).