摘要:
A travelling mine roof support to which a slide in form of a Ushaped upwardly open trough is connected by fluid operated cylinder and piston means so that the slide and the mine roof support may be stepwise advanced toward the mine face during mining of the latter. The slide is constructed to support and guide the upper and the lower run of an endless scraper conveyor and it includes conveyor channel means comprising a guide member having a pair of side wall profiles connected by a transverse wall upwardly spaced from the bottom wall of the trough for guiding the upper run of the conveyor. The guide member is arranged between the side walls of the trough tiltably between a working position in which the transverse wall thereof extends substantially parallel to the bottom wall of the trough and a raised position providing access to the lower run which is guided by a pair of further side profiles located between the transverse wall of the member and the bottom wall of the trough.
摘要:
A travelling face support has an attached extensible shield which, besides providing the means of shoring up the roof of the seam and providing a connected coal cutting shield, has both a packing shield to protect the coal cutting area and a floor beam. One or more pull-back cylinders act upon a supporting frame divided into sections along its length. A continuous recess, transverse to the direction of the prop conveyor, is provided in each section of the supporting frame to receive a forward longitudinal section of the corresponding floor beam. A lifting device, which is supported on the prop floor, is fixed in a recess of a section of the supporting frame in the rear part of the extensible shield beneath the coal cutting shield. The lifting mechanism of this device is used to control the position of the forward longitudinal position of a heel plate of the supporting frame section.
摘要:
A method for the desulphurization of pig iron envisioning a continuously flowing pig iron stream having a descending flow portion in which a desulphurizer ascends in opposite flow direction.
摘要:
The invention relates to a device provided for conveyor means in mining and serving for the butting or forward pressing devices for the conveyors and/or of units of the roof support casing system, said device having several bearings to which the units of the roof support systems respectively are connected at predetermined distances. These bearings on the one hand maintain somewhat the spacing of the units of the casing system and, on the other hand, they provide a sufficiently fixed connection with the conveyor, to which the units respectively may move up.
摘要:
An arrangement for positioning a device for closing and opening a pressure vessel, has a positioning vehicle arranged to carry the device, and a positioning track attachable to the pressure vessel and extending from just above the floor under the pressure vessel to the pressure vessel so that the positioning track guides the positioning vehicle when the latter is displaced from the floor to the pressure vessel to close the latter, and from the pressure vessel back to the floor to open the pressure vessel.
摘要:
A compound steel material of high corrosion resistance is manufactured by alloying a carrier material of deep-drawing grade with a carbide and nitride forming substance, compounding the alloyed carrier material with a chromium steel material of normal carbon content, followed by annealing the compound steel material at a temperature and for a time period sufficient for the carbon content of the ferritic chromium steel coating layer to be reduced to between 0.001 and 0.003% so as to increase the corrosion resistace of the chromium steel material to that of a superferritic material. Prior to annealing, the compound steel material may be rolled to a fine sheet. The carrier material used in the method of the invention is a deep-drawing steel of at most 0.12% of carbon, while the ferritic chromium steel material has at most 0.1% of carbon prior to the annealing. The carbide and nitride forming substance may be titanium whose content in the alloyed carrier material is preferably between 0.5 and 2%. The thickness of the ferritic chromium steel coating layer is between 50 and 500 .mu.m, the annealing temperature between 650 and 900.degree. C., and the annealing time period between 8 and 72 hours.