218 results about "Concretion" patented technology

The present invention improves significantly the success rate of lithotripsy and reduces the risk of tissue damage, by injecting temporary plugs in front and behind a concretion (for extracorporeal lithotripsy) or behind a concretion (for intracorporeal lithotripsy). One aspect of the present invention relates to injecting an inverse thermosensitive polymer solution into a lumen, thereby preventing the migration of a concretion, or its fragments, upon extracorporeal or intracorporeal lithotripsy.

The invention relates to an improved apparatus for the comminution of concretions in vivo by controlled, concentrated cavitation energy using two shock wave pulses with a specified time delay and pressure relationship, with the first shock wave pulse being used to induce a transient cavitation bubble cluster near the target concretion, and the second shock wave pulse to control and force the collapse of the cavitation bubble cluster towards the target concretion with concentrated energy disposition while avoiding injury to surrounding tissue. The invention contemplates the use of an improved combined electrohydraulic or electromagnetic and a piezoelectric annular array shock wave generator to produce improved stone comminution with reduced tissue injury in vivo.

One aspect of the present invention provides a method for the treatment of lithiasis, which mitigates the risk of damage to surrounding body tissue when removing a calculi (e.g., biological concretions, such as urinary, biliary, and pancreatic stones) that obstructs or may otherwise be present within a body's anatomical lumen. In one embodiment, the instant invention provides a method of using a polymer plug to occlude a lumen distal to a calculi, whereby calculi fragments resulting from lithotripsy are prevented from traveling up the lumen. In certain embodiments, a dual lumen catheter is utilized to inject two solutions proximal to the calculi, the mixing of said solutions causing a polymer plug to form.

A dynamic compaction soft foundation reinforcing method by combing layered dead weight and pre-pressing drain concretion includes: filling a water-isolation cofferdam; a water collecting well is arranged in the middle of the cofferdam; a sand layer of 0.5m to 0.8m is filled by hydraulically filled or manually filled on the original water-drained ground; a horizontal drain pipe is embedded in the sand layer to carry out first earth hydraulic filling; a drain pump is arranged in the water collecting well to continuously drain water; when the thickness of hydraulic filling reaches the designed elevation of the first layer, the hydraulic filling is stopped; when the surface of the hydraulic filling earth forms a hard shell layer with a thickness of 30m to 40m under the actions of vaporizing and dead weight drain, the hydraulic filling to a second layer and a third layer are carried out according to the steps; even a required hydraulic filling height is designed; finally hill-skill soil or mixed backfill soil and sandy soil are back filled on the layers; dynamic compaction is carried out after leveling. The invention has the technical economic indexes of fast speed, saving investment, small settlement after construction and high surface layer bearing capacity, etc., and has remarkable technical advantages on lower ground elevation and the projects of polder reclamation by hydraulically fill the soft soil like silt.

The invention discloses a controlled-release multilayer drug-loaded artificial bone and a preparation method thereof. The controlled-release multilayer drug-loaded artificial bone is a multilayer structure which is coated layer by layer and is composed of artificial bone carrier materials loaded with drugs or a multilayer structure which is coated layer by layer and is formed by alternately arranging the artificial bone carrier materials loaded with the drugs and artificial bone carrier materials loaded with no drugs; the outline of the controlled-release multilayer drug-loaded artificial bone can be cylindrical, cuboid, square or irregular; and the artificial bone carrier materials loaded with the drugs at different layers comprise the same or different drugs. The controlled-release multilayer drug-loaded artificial bone is prepared by adopting a three-dimensional stereoscopic printing rapid prototyping technology, and the drugs distributed at the different layers are released from outside to inside layer by layer, thereby being capable of realizing multidrug combined action, regulating the releasing sequence and time of the drugs and selecting appropriate drugs to load so as to achieve the individualized treatment goal. The invention can be applied to carrying out local chemotherapy and filling and repairing bone coloboma after eradication focuses of various infections, concretions, tumours and the like of the orthopedics department.

The invention provides a soft soil foundation treated by chemical solution-combined injection electroosmosis method and a construction method of the soft soil foundation, and belongs to the technical field of processing of the soft soil foundation. A metal electrode is inserted into the soft soil foundation; different chemical solutions are injected into a positive electrode and a negative electrode respectively, and a direct current is fed; under a direct current field, water and a cation solution which have positive charges flow towards the negative electrode, and an ion solution with negative charges flows towards the positive electrode so as to form electroosmosis chemical reaction; at the same time, the water is pumped and discharged from the top of the negative electrode so as to reduce the water ratio in the soil, accelerate concretion and compaction of the soil, and enhance the strength of the soil; and precipitates produced by the chemical reaction can cement the soil particles. Compared with other soft soil foundation treatment methods, the construction method has the advantages of more environment friendliness, lower energy consumption and saved treatment cost, and large-size mechanical equipment and building materials such as cements, sand, stones and the like are not required. By the method, the construction process is simple, the operability is high, the quality is convenient to control and detect, and the intensity of the soil is enhanced obviously.

The invention discloses a strap-down inertial navigation air initial alignment method for a floating aircraft, belonging to the technical field of inertia. According to the method, air coarse alignment of a floating aircraft inertial navigation system is realized by using a global positioning system (GPS)-assisted initial concretion analysis type coarse alignment method, inertial navigation attitude information is roughly acquired, and position information and speed information are directly acquired by a GPS; on the basis of coarse alignment, the condition of a large-orientation out-of-alignment angle is considered, a Kalman filtering state equation comprising a coarse alignment out-of-alignment angle error and a Kalman filtering measurement equation for measuring by taking navigation solving and speed difference measured by the GPS as the quantity are established, and an out-of-alignment angle is estimated through Kalman filtering. The attitude of a carrier can be tracked in real time through the GPS-assisted initial concretion analysis type coarse alignment method, the interference of an angular motion and a linear motion is shielded, and coarse alignment time is shortened greatly. The method provided by the invention is applicable to the motion conditions of the horizontal motion and rotation of the carrier, is high in universality and is feasible; expensive equipment does not need to be added.

The invention discloses an insulating refractory material of polymerized silicon and aluminum and the preparation method, applied in construction and industrial facilities, which is characterized in that: excitation, gas evolution and polymerization are carried out for industrial wastes abundant in aluminum oxide, silicon dioxide, and the complex of the silicon dioxide and aluminum oxide, so as to obtain a three-dimensional aluminum silicate minerals with an internal structure made of a plurality of phases from amorphous to semi-crystalline inside, and an internal form in silica tetrahedron and alumina tetrahedron; a plurality of molecules are linked mainly through ionic or covalent bonds, the mechanical properties of the inorganic concretion are externally presented. The raw materials are composed of silicon and aluminum materials as kaolin, fly ashes, coal gangue, cinder, and red mud; without adding any gelled materials, a high temperature and corrosion resistant porous long-chain structure is formed with an intensity over 0.8MPa and a thermal conductivity coefficient of 0.087 (kilocalorie / meter x hour x centigrade). The insulating refractory material is applied not only for the heat insulation wallboards in the building but also for the heat insulation and preservation of the industrial thermal pipelines and facilities.

The invention discloses a construction method for a protecting slope of a reinforced-concrete retaining wall. The construction method comprises the following steps: (1) measuring and setting-out; (2) excavating a foundation pit; (3) paving a concrete cushion layer; (4) manufacturing and installing foundation reinforcement; (5) arranging a foundation template vertically; (6) casting foundation concrete; (7) arranging a wall body template vertically; (8) casting wall body concrete; (9) curing the wall body concrete; and (10) removing the wall body template. The concretion method disclosed by the invention has the advantages that (1) the design is scientifically and strictly based on the specification requirement, the plan is detailed and careful, the quality of the retaining wall is good, the reworking and the waste are avoided, and the defects of blocking of pitted surfaces, interlayers and water draining holes and the like in the existing retaining wall are overcome; and (2) the integrity of the whole retaining wall is enhanced and the performance of the retaining wall is improved to certain extent.

A medical device and method for breaking a concretion in a body into smaller pieces and removing the pieces from the body are described. The device comprises a dilator sheath, a lithotripsy probe, a tubular member, and a retrieval basket. The dilator sheath adapted to penetrate into a passage of the body to reach the location where the concretion is located. The lithotripsy probe is configured for shattering the concretion into smaller pieces. The tubular member is mounted within the dilator sheath adapted to permit the lithotripsy probe to be inserted into the tubular member. The retrieval basket is coupled to the tubular member, and configured for entrapping the concretion and the smaller pieces for their extraction from the body. The retrieval basket comprises a structure constituted by a plurality of filaments extending from a basket proximal end towards a basket distal end, and then returning to the proximal end after forming a plurality of filament loops in the basket distal portion, and a plurality of filament strands at the basket proximal portion.

The invention discloses a water soluble phenolic acid extract which is obtained by extracting from a medical plant of a clerodendranthus spicatus by the chemical method. The pharmacological experiment testifies that the extract has strong physiological activity and especially has strong physiological activity of resisting the generation of uric acid, and the extract is used for remedying the pain-louse and has good effect of the treatment towards the urinary tract infection or the urinary tract concretion and has little toxic and side effect.

The invention discloses an indoor quick load solidify tester and a relative method, belonging to the test technical field of deformation character index of rock project and building foundation. The device is composed of an upright load device, a solidify container for containing sample soil, a liquid pressure sensor, a deformation sensor, a static resistance strain gage, and a PC computer. And the test method comprises that (1), sampling, vacuuming until saturation, (2), putting the sample soil into the solidifying container, sealing the bottom of the sample and connecting with the sensor, (3), arranging the solidifying container into the upright load device, and mounting the liquid pressure sensor and the deformation sensor at relative positions, processing hole water pressure and upright deformation test, (4), using the static resistance strain device and the PC computer to pick, transmit and record static signal. The invention can be used in the condition with short construction period, high test accuracy and lack fund.

The invention discloses a mine fracture grouting material and a usage method thereof. The mine fracture grouting material comprises raw materials of, by weight, 5.5-6.0kg of superfine cement, 0.5-1.0kg of silica powders, 2.5-3.0kg of coal ashes, 0.3-0.5kg of bentonite and 0.05-0.12kg of water reducing agents. According to the mine fracture grouting material, the superfine cement is used as a host material and supplemented by other materials, and the main fracture grouting material has the advantages of being high in concretion rate, tiny in expansibility, low in bleeding rate and good in stability; when the water cement ratio is 1: 1, the 28-day compression strength of the mine fracture grouting material can reach 15MPa; the mine fracture grouting material can be well injected and permeated into fine fractures of rock masses; the problem of ground water environmental pollution caused by chemical grouts is absent, and engineering requirements of reinforcement and impervious effects are satisfied; and grouts manufactured by the mine fracture grouting material can be applicable to mine water management and micropore fractured rock mass reinforcing engineering of hydraulic and hydro-power engineering rock masses.

The invention discloses a low-permeability fractured reservoir oil well water-plugging and screening method and relates to the technical field of oil well water plugging technology for oil exploitation. The method includes the following steps: taking and mixing 0.05-3 parts of screening agent and 100 parts of carrier fluid; injecting the mixture into a stratum under the condition of 0 DEG C-90 DEG C to screen a fractured wall face; taking and mixing 0.1-1 part of main plugging agent and 100 parts of clean water; injecting the main plugging agent into the stratum under the condition of 0 DEG C-90 DEG C to plug a water outgoing layer and a fracture; using the clean water to replace the main plugging agent to enter an oil well reservoir stratum; closing an oil well and waiting for concretion; opening the oil well, pumping and starting production. The low-permeability fractured reservoir oil well water-plugging and screening method solves the technical problem that the plugging agent is easy to cause damages to the reservoir stratum and is wasted in large quantity when existing general water plugging processes are adopted for construction, and opens up a new way for low-permeability fractured water logging oil well water plugging technology.

The invention discloses a method for preparing chitosan and hydroxyapatite composite bone support materials, which comprises the following steps: a precursor solvent of hydroxyapatite is prepared, and mixed solvents of chitosan and hydroxyapatite are prepared and placed still for defoaming; mixed solvents are evenly applied on the surface of a mould, and placed in alkalescence concreting liquid at room temperature to be concreted into a membrane; then the mixed solvents are injected into the mould, and the mould is put into the alkalescence concreting liquid again; after concretion and demoulding, gel compounded by the chitosan and the hydroxyapatite is obtained, and distilled water is used for washing the gel to neutrality; and only predry, re-freezing and desiccation in vacuum are needed. The support materials have the advantages of three-dimension sequence, good mechanical properties and high porosity, thus promoting the absorption and the growth of cells. The hydroxyapatite granules are evenly distributed in the chitosan kinetosome and can keep the continuous, stable and adagio release of calcium ions and phosphor ions in hydroxyapatite from chitosan kinetosome during the bone repairing process, thus avoiding burst release.

The invention discloses a method to reinforce soft foundation based on gas pressing discharging and its gasbag. The method is: exhaust gas in cavity of inflatable body and put it into the reinforced soft foundation. Utilize inflatable body to press soil layer for a period of time and release gas in cavity when the soil layer reach density requirement. Take the inflatable body out of soil layer and fill the hole with soil. The gasbag in this method is composed of gasbag body with elastic multi-cavity and inserted link. The inner layer of gasbag is rubber and external layer is lyophobic textile. Both layers are adhered by glue. The invention has reused gasbag, small energy composing of pressing discharging, small composition of sandstone and low comprehensive cost. It has great concretion pressure, short reinforced time and good reinforced effect, which can be applied in reinforcing soft foundation of different fields and ranges.

A medical device and method for breaking a concretion in a body into smaller pieces are described. The device comprises a combined probe including a laser waveguide probe and a nanosecond electro-pulse lithotripter probe. The method includes applying the laser waveguide probe to the surface of the concretion, and treating the surface with laser radiation to create a defect. The method also includes applying the nanosecond electro-pulse lithotripter probe to the area of the defect created by the laser waveguide probe, to provide a spark electrical discharge through the concretion.

The invention relates to a thin coal bed fully-mechanized mining scraper conveyor comprising a machine head (1), a machine tail (12), a middle groove (6), a scraper chain, and the like, wherein middle plates of the machine head (1) and the machine tail (12) are horizontally arranged and form an included angle of 0+6 to 0-20 degrees with the middle plate of the middle groove (6) and positioned at the same height; scraper running lower chain ways (4 and 9) of the machine head (1) and the machine tail (12) are in shapes of inverse curves; and the bottoms of the machine head (1) and the machine tail (12) are provided with hoistable poppets (2 and 11) capable of adjusting the heights of the machine head (1) and the machine tail (12). The invention can solve the problems that triangle coal is not remained at both ends of a thin coal bed fully-mechanized mining face, and returning coal is conveyed by the lower chain ways (4 and 9); a machine head coal dropping device and a machine tail recovering device can solve the problems of poor coaling effect of a thin coal bed coal-winning machine and recovery cleanness of float coal positioned at both ends of the thin coal bed fully-mechanized mining face; the scraper chain with a wide chain pitch can permit larger-lump bastard coal to pass through a bottom bracket of the coal-winning machine; the invention is suitable for the fully-mechanized mining of a thin coal bed dug from top to bottom, especially suitable for the fully-mechanized mining of a thin coal bed containing ferric sulfide concretions or / and hard gangues, and also suitable for the fully-mechanized mining of a moderate thick coal bed and a thick coal bed.

The invention relates to a separated blue water local mine production system, belonging to the underwater project technique. It comprises: a surface main ship, a mine producing diving device, and a lifting system. Wherein, the lifting system is formed by several lifting diving devices, which are unmanned non-cable diving devices; the mine producing diving devices are unmanned cable diving devices via the umbilical cord cable connected with the main ship, while the umbilical cord cable comprises the electric and information transmission channel; when lifting the diving devices, the mine producing diving devices and the surface main ship via the water sound to position and transmit information; when in working, the mine producing diving devices produce mine at the bed and lifting diving devices move between the mine producing diving devices and the main ship to transfer collected mine sample, and the fully loaded lifting diving devices is guided to the main ship via the mine producing diving devices; and the empty lifting diving devices is guided to the mine producing diving devices from the main ship. The invention is flexible with lower cost, high practicability, the application for variable mine sources as multi-metal concretion, abundant cobalt crustization and metallic sulfide beds.

The invention discloses an in-situ remediation method of a heavy metal polluted site, which is characterized in that a stabilizing agent is completely covered on the polluted site through throwing a heavy metal-chelating stabilizing agent on the polluted site with low water content, thus secondary pollution of heavy metal pollutants to the environment is avoided; the polluted site is turned and stirred for multiple times by using an amphibious excavator, the stabilizing agent and the heavy metal pollutants can fully react to form a stable material, thus ensuring that the leaching concentration of heavy metals is in an allowable range; and concretion is carrying out for multiple days through airing, the treated site can be used for soil improvement, landscaping or landfill backfilling according to difference of the water contents and the heavy metal in and outlet concentrations. Therefore, compared with the prior art, the in-situ remediation method has the advantages of ensuring stabilizing effect of the heavy metals, importantly solving the problem of soft foundation encountered by common stirring modes, and ensuring that chemicals are fully mixed with the polluted soil through adopting common excavators for site stirring if the foundation is allowable.

The present invention relates to pre-treatment of tail ore, concretion cementing material obtained therewith and their preparation process. Tail ore in 30-90 wt%, salts connecting K+, Na+, Ca2+, Mg2+ and / or Fe2+ ion and acid radical ions in 0.1-8 wt%, and other material containing crystal water, hydroxide radical, hydroxyl group, CO22 or other volatile components in 5-60 wt% are mixed, and the mixture is then hydrothermal alteration reacted at 200-900 deg.c. Then, the hydrothermal alteration reacted material in 50-90 wt%, cement clinker in 0.1-29 wt%, blast furnace slag or other high temperature treated waste in 0-30 wt%, gypsum in 0-8 wt% and rock forming agent in 0.1-5 wt% are mixed and ground to obtain cement powder. The cement powder has high strength and high stability.

The invention discloses a novel deep building foundation pit supporting system which comprises front-line piles, a water-retaining curtain, a top beam, rear-line piles, an anchor rope and sand pulp, the front-line piles are positioned at the side of a building foundation pit, the water-retaining curtain is tightly abutted against the inner sides of the front-line pile, the rear-line piles are positioned in soil body at the inner side of the water-retaining curtain, the tops of the front-line piles and the rear-line piles are provided with the top beam integrally poured by reinforced concrete, wherein the top beam is provided with a protruding part towards the inner side at the top of the rear-line piles and is provided with the vertical anchor rope in the soil body at the inner side of the rear-line piles, the lower end of the anchor rope vertically extends into rock body and the sand pulp is poured into the rock body for concretion, and the upper end of the anchor rope is tightened with and is concreted with the protruding part of the top beam. Because the vertical anchor rope is arranged in the soil body at the inner side of the rear-line piles and the drilling in the soil body is fast and good, the invention greatly improves the speed, increases the construction efficiency, saves the time, reduces the loss of a drill bit, lowers the construction cost, and achieves better profit.

The present invention belongs to a building material, in particular to a self-concretion material of steel residue powder and coal ash. The self-concretion material of steel residue powder and coal ash is characterized in that: the material is made of the mixing with steel residue, coal ash powder, industrial waste gypsum and alkaline catalyzer; the molar of the industrial waste gypsum is 1-15 percent of the total molar of the steel residue, coal ash powder, industrial waste gypsum and alkaline catalyzer; the molar of the alkaline catalyzer is 0-3 percent of the total molar of the steel residue, coal ash powder, industrial waste gypsum and alkaline catalyzer; the molar ratio between the steel residue and the coal ash powder is 1: 2-4: 1. (The material can not only be used alone, but also be used for stabilizing the road base of detritus and grit and the building brick.) The material is characterized in low cost.

The invention relates to a novel low-temperature concretion adhesive for cold press iron coke and a preparation method thereof and develops a high-efficiency adhesive with low cost, good molding property, low impurity content and no production of secondary pollution. By using the adhesive, coke powder can be used in a large proportion for preparing iron coke, and the iron coke has cold strength for meeting the requirements of operation and drop under the condition of cold press molding and thermal strength for meeting the requirement of smelting under the condition of low-temperature concretion. The adhesive is prepared by the method as follows: 0.5 to 1.5 organic high molecular polymer, 5 to 7 silica sol or 11 to 13 silica gel and water are mixed; and a stabilizing agent accounting for 0.05 wt% to 0.6 wt% of the mixed solution is added to react for 1.5 hours to 3 hours at 1.2Mpa to 1.4Mpa and 170 DEG C to 190 DEG C. The solution has high viscosity because components in the adhesive are grafted and bridged into a netted structure and also has high dispersivity under the action of the 0.05 wt% to 0.6 wt% of stabilizing agent.

The invention discloses a treatment method for grouting a sand-layer foundation on the condition of flowing water, comprising the following steps: 1. adopting a spindle swing rig to process a plurality of grouting holes which are partially overlapped on the strengthened sand-layer foundation; 2. inserting a grouting pipe into the grouting holes and injecting grouting slurry which is formed by the mixing of mud or two materials of cement and mud to the sand-layer foundation on the condition of flowing water from the grouting pipe; 3. directly injecting pure cement slurry into the same one drilling hole or re-adopting the spindle swing rig to process a plurality of grouting holes which are partially overlapped at the position where a first batch of slurry is grouted after the slurry is precipitated and cured, and then inserting the grouting pipe and injecting the pure cement slurry; and 4. using a waterstop to block the grouting holes after the slurry is injected to each grouting hole. Compared with the pure cement slurry, the treatment method for the grouting of a sand-layer foundation on the condition of flowing water has low cost, good flowability and permeability, high concretion rate, simple technology equipment, and convenient operation.

This invention relates to the arsenide gallium single-crystal growth with level three temperature areas gradient concretion method, the character as follows: the furnace where the single-crystal grows is not moved; the temperature of high temperature T1 decreases gradually according to the single-crystal shaping point temperature, and the decreasing rate inosculates to the single-crystal growth rate.

The invention relates to a successive rigid-frame bridge structure with gradient variation of concrete density. The upper structure of the bridge uses three concrete materials, wherein, mid-span base material uses strong light aggregate concrete with dried apparent density of no more than 1950kg / m3 so as to reduce structure weight; the base material at the concretion position of a frusta and a beam uses strong common concrete with dried apparent density of no less than 2300kg / m3 so as to satisfy higher compression resistance and splitting resistance strength the concretion position of frusta and beam; the base material of primary beam between mid-span and the concretion position of frusta and beam uses strong light concrete of fiber toughening and splitting resistance with dried apparent density of 1950kg / m3-2300kg / m3 so as to reduce structure weight, improve concrete splitting resistance performance and reduce adverse impacts caused by constrict creep. The invention can handle the technical problem of serious cracking between the mid-span downwarp of successive rigid-frame bridge and a box girder through the optimized combining matching of the material and the structure and the collocating way of the optimized prestress bundle.

The invention discloses a soil water-gas collapsibility-consolidation-penetration combined determinator. The determinator comprises a collapsibility-consolidation-penetration permeameter, a water seepage coefficient determination system and an air permeation coefficient determination system. The collapsibility-consolidation-penetration permeameter comprises a base and a cutting ring. The cutting ring is filled with a soil sample. The top end of the soil sample is provided with a pressurization control system. The pressurization control system is provided with a dial indicator for determining displacement of a piston in the pressurization control system and a compression gauge for determining air pressure. The water seepage coefficient determination system and the air permeation coefficient determination system are connected to the collapsibility-consolidation-penetration permeameter through pipe ports. The determinator utilizes a modularization design, can carry out a standard height soil sample test, can prepare soil samples with different heights according to demands and test them and can realize simultaneous determination of a penetration coefficient, an air permeation coefficient, a concretion coefficient, a loess collapsibility coefficient and a penetration coefficient and air permeation coefficient after loess collapse. The determinator has the characteristics of good flexibility, short test period, stable and reliable pressure control, labor and time saving and high cost performance.

The invention relates to a process for stoping low coal seams containing ferric sulfide concretions and hard parting bands, which adopts a fully mechanized mining process to mine coal. Working face equipment comprises a drum shearercoal-mining machine, a hydraulic support, a scraper conveyor, and the like, wherein the drum shearercoal-mining machine adopts a wide high-power high-strength drum for narrow cutting and deep cutting; the hydraulic support adopts a hydraulic shield support for advancingmoving quantitively by in different times and stretching the support in one-stepce; and water is injected into the working face for softening before stoping. The fully mechanized mining level can be enhanced by adopting the scraper conveyor with a middleedian plate straightly arranged at the head and the tail of the scraper conveyor, and a radio remote control method for the coal-mining machineshearer with the working face remote-controlled in segments automatically. The advancing jack hydraulically-controlled loop of the hydraulic support is formed into a separately push / pull and quantitively grouped advance charging loop bycomprises an adjacent support pilot control reversing valve, a differential valve, a quantitive cylinder and an alternate valve which form a separately push / pull and quantitively grouped advance charging loop. The invention can realize the fully mechanized mining forof the low coal seams containing the ferric sulfide concretions and / or the hard parting bands, and solves the difficult problem which is not solved at home and abroad for a long time. The invention can be used for mining low coal seams containing other concretions, ordinary low coal seams, medium-thickness coal seams and high coal seams.