The results showed the frictional coefficient of the prepared material was stable ,around 0.35±0.05 ,frictional loss was 1/2—1/4 less than that of common asbestos friction material ,and the cost was decreased by 1/3—1/2. The friction material was already applied to YWZ— 630/201 and YWZ— 800/320 brakes, Volga and Beijing cars, and run well without noise.
Third, the paper illustrates the operation principle of the simulated load system-magnetic power braker, and designs the waveform generator, protection circuit and drive module of magnetic power braker.
This paper introduces the structure and principle of the testing system of hoisting machinery stopper, the system adopts computer technique, which makes the automation be realized from the stopper test to the data collection and treatment.
Through the analysis on the main safety defects of the old standard elevators, this paper puts forward some corresponding safety measures, which include adding the up-overspeed protective device on the carriage, using the safe stopper, adding the rotating members' guard, and adding the emergency electric operation switch and motor's temperature detecting device, etc.
Three applications of this theory are presented including closed characteristics on convex hypersurfaces and brake orbits on bounded domains.
Wear mechanism of disc-brake block material for new type of drilling rig
Topography and elementary components of the brake block's wear surface are analyzed by employing SEM and EDAX patterns, revealing its tribological behaviour and wear mechanism.
When the frictional temperature is lower, the surface film of the brake block is thinner, dense, smooth with plasticity, and divided into the mixture area, Feabundant area, carbon-abundant area and spalling area.
At the beginning of wear, the hard peaks from the friction surface of the disc-brake plough on the surface of the brake block.
As a result, a plasma "stopper" was formed in the cathode cavity near the hole.
The stopper hindered the plasma-forming gas flow from the cathode cavity into the vacuum chamber.
The magnetoplastic effect in mechanics of nonmagnetic crystals is attributed to spin evolution in the spin-selective nanoscale reactor created by electron transfer from a dislocation to a stopper.
In this "dislocation + stopper" system, dislocation depinning is facilitated because the Coulomb attraction between the dislocation and the stopper is switched off.
In ionic and covalent crystals, a nanoscale reactor is created when an electron is transferred in a "stopper + pinned dislocation" system and when a dislocation encounters a dangling bond, respectively.