Loosening method for rock having different strength
FIELD: mining industry, as well as hydraulic, road, agriculture and other building, particularly to perform open cast mining and other woks by rock loosening.
SUBSTANCE: method involves obtaining information concerning main and structural-and-strength rock properties on the base of estimation of data of primary and post-authorization prospecting, as well as production prospecting; detailed rock zoning to separate production blocks and unit blocks characterized by uniform rock at borders thereof; writing computer program; automatically loosing rock of each unit block by most effective method, namely by mechanical, pneumatic, blast drilling or physical one performed with the use of all-purpose mobile rig tools. Above rig includes computer system, device provided with one, two or three replaceable teeth, with plate-like metal pins and with hydraulic cylinders. The rig also has device adapted to create holes in unit block and wedge out thereof, drilling device and charging device, laser charge initiation system, local shelter with damping means, device for rock cutting by applying pressurized air and impacts to rock and auxiliary excavation device.
EFFECT: increased efficiency of rock preparation for further cutting and loading and for solid mineral field development as a whole.
The invention relates to the mining industry, hydraulic engineering, road, agricultural, and other sectors of construction and can be used in the manufacture of various works involving loosening of rocks and building soil.
Widely known traditional methods of cultivation of different rocks: rock, half-rock, dense and frozen composing work on arrays, such as arrays of ledges ore quarries and coal mines, , , each of which is carried out using technical, or physical, or chemical-physical means, but mainly with the help of explosives and are monopsony. For loosening of rocks of a certain strength using a corresponding unit: Ripper on the basis of a tractor, bulldozer-loosening, drilling machine and car charger, etc. Because most rocks and especially of solid mineral deposits are composed of rocks of different strength with the strength coefficient on a scale Dev from 4-6 to 28, it leads to sadasivuni on a single production facility various means, to a significant decline in productivity, environmental, and social security, to increase capital and operating costs to prepare the ku rock for excavation.
As the closest analogue  adopted the method of development of deposits of solid minerals, including operational intelligence, the allocation of operational blocks on the quality of minerals and rock strength, crumbling rock drilling and blasting method using a horizontal or slightly inclined boreholes with a diameter of from 50 to 150 mm, the loading of EXPLOSIVES and blasting under the local mobile shelter, subsequent excavation practicing blown blocks. The disadvantage of the prototype is the possibility of loosening of rocks in only one way - drilling and blasting.
Thus, to the General disadvantages of these methods loosening of rocks should include the need to use for loosening rocks a particular strength of the respective unit or set of units, as, for example, when widely used currently drilling and blasting method.
The main result of the invention, including technical, is to increase the efficiency of loosening of rocks and the development of solid mineral deposits in General, as well as various construction and mining operations, connected with the necessity of destruction of rocks and building soil.
This result is achieved by the fact that in the universal way of loosening raznopolosnyh mountain p is the genus, including obtaining information about the main structural strength properties of all types of rocks array, detailed zoning of rocks within working operating horizon or its individual plot, the allocation of operational blocks and borders - the elementary units represented by homogeneous fortress rocks, forming a computer program, loosening raznopolosnyh rocks, auxiliary excavation the excavation and loading of the rock mass in small volumes, loosening raznopolosnyh rock field or array construction soils carried out selectively in accordance with their structural strength properties, which distinguish the elementary blocks, using the most effective way - one of the mechanical or pneumatic or explosive or physical, which is implemented in an automated process mode using a computer program universal mobile unit, with a dense and relatively weak half-rock breed loosen mechanically with the use of technical devices, equipped with one, two or three teeth on traditional type mounted Ripper, any device with plate metal pins, introduced in the rock is hydrocylinders, device for the formation of holes in the pattern elementary unit and separation of waste elements from the array block their rasklinivanie, relatively strong half-rocks and hard rocks of medium strength and destroy using the power of compressed air, strong half-rocks and hard rocks elementary blocks destroy the drilling and blasting method, and wells or bore-holes with a diameter of 16-150 mm Buryats rotary or rotary-percussion or percussion-rotary or combined method, blow up the bore-holes and wells of small diameter of the detonating cord or patronized nizkobyudzhetnym explosive, a small diameter cartridge or natronomonas nizkobyudzhetnym explosive, descobrindo explosive mixture initiate laser pulse, blasting is performed under local shelter mobile unit, small inclusions of rocks, as well as the oversized destroy mechanical shock, while the excavation and loading of the rock mass produce auxiliary excavation device, and the execution of all processes and operations associated with loosening raznopolosnyh rocks, manufactured using universal mobile unit that includes a complex variety of devices to implement the mechanical way rychle the Oia rocks, drilling wells and bore-holes, loading and blasting, laser system initiation, the computer system, the device for breaking rocks by the energy of compressed air and blow, a device for supporting excavations excavation of the rock mass in small amounts.
A comparable analysis with the prototype of the differences of the proposed method, which consists in providing a selective loosening of diverse quality and raznopolosnyh rocks within each operational unit by using the most effective for the specific difference between rocks of the way of the destruction of those few that can be implemented using the universal mobile unit, equipped with a set of structural devices that allow rational loosening rocks and building soil, or various mechanical, or pneumatic, or drums, or drilling and blasting method using wells or bore-holes of small and small diameter, exploded under a local shelter that can be used and some relatively simple physical methods of cultivation, such as hydroelectric.
Thus, the claimed universal way of loosening raznopolosnyh and different rock meets the condition novizny the process of exploring other solutions in the field of machinery safety signs, distinguishing this invention from the prototype and associated with achieving the stated technical result, have not been identified and therefore provide the requirement of inventive step.
The inventive method illustrates the drawing, which schematically depicts a generic unit. In the drawing, the following notation:
1 - mastering the horizon of the Deposit and its plot;
2 - operational unit, folded raznoobraznymi or different rocks;
3 is a basic block, folded uniform in strength or quality and structure of the rock;
4 - universal mobile unit;
5 is a device for mechanical loosening of rocks one, two or three teeth;
6 is a device for the mechanical destruction of rocks break;
7 is a device for mechanical loosening of rocks by cutting or chipping;
8 - installation for drilling wells and bore-holes;
9 - device for loading wells and bore-holes;
10 - device for initiating detonation of explosive charges;
11 - the local shelter for the implementation of the blasting of rocks;
12 is a device for implementing the loosening of rocks by the energy of compressed air;
13 - portable compressor;
14 is a device for the destruction of separateness strong hornyhead shock method;
15 - auxiliary excavation device;
16 - diesel-electric installation.
Method of loosening raznopolosnyh and different rocks is as follows.
Make a selection in each working horizon 1 field or array construction rocks operational blocks 2, and in them - elementary blocks 3 on the basis of geological information obtained sequentially in several stages:
in the first stage, allocate petrological, structural and morphological gornorudnaya education within career fields or specify them on the basis of information obtained in the process delicensing exploration
in the second stage, highlight or clarify previously allocated blocks within petrologically homogeneous blocks on the basis of information obtained during post-licensing exploration
in the third phase adjust petrographically homogeneous units based on the additional information set out in the design process of the development of minerals, some of its plot or construction of an object
in the fourth stage secrete structurally homogeneous blocks within petrographically homogeneous blocks on the basis of geological information received by the CE failover upstream horizon or block, and its extrapolation to the next adjacent block, provided for mining,
in the last step, finally form the basic blocks of 3 or clarify previously allocated on the basis of operational mining and geological information, quickly get jalagamparai service by the company as a direct instrumental measurements and quantitative evaluation and visual assessment entered into the computer system universal loosening unit 4.
After extraction of the elementary units 3 for each of them establish the most efficient technology loosening their constituent rocks, including both the method and sequence of loosening, using the computer system universal unit 4, and in close connection with the means and methods further auxiliary or main excavation excavation loosened rocks.
When this dense and some weak half-rock rock f≤6-8 on a scale professional Dev loosen mechanically by means of technical devices 5, 6, 7 universal mobile unit 4: unit 5, provided with teeth on type mounted Ripper, device 6 for removing rock that rasklinivanie, device 7, the cutting or shearing the rock.
Regarding the BAP is the cue half-rocks and hard rocks with f> 7-8 destroy the drilling and blasting method, Abueva elementary block or two or three adjacent elementary unit of horizontal or slightly inclined wells, or their combination, small or small diameter within 16-150 mm Drilling wells or bore-holes is made by setting 8 mobile unit 4, including the complex used in mining and construction industry lightweight rotary drilling equipment, rotary-percussion and percussion-rotary types, each of which is used depending on the fortress of rocks that are installed permanently in the process of drilling wells, and the well can be drilled one, two, or even several by the way, if it takes place in rocks that are significantly different from each other by drillability, and the transition from one drilling mode to another is done automatically.
Wells or boreholes charge detonating cord, or explosive mixture or the packaged explosive in accordance with their diameter, strivesto rocks and the necessary degree of fragmentation, with the security requirements of loading and blasting holes with the charger 9, a hardware-based charging machine operated mines.
Done is make short-delay and dispersed downhole, crosshole and miragee blasting explosive charge, initiating their laser pulse passed through the system laser initiation device 10, under the local shelter 11 mobile unit 4.
Loosening of rocks with medium strength f=7-9, when the mechanical method is no longer effective, and drilling and blasting is not yet appropriate, carried out using the energy of compressed air that is being implemented with the help of the device 12 and portable compressor 13.
The destruction of the inclusions of hard rocks in the array of the ledge and oversized solid rock is performed by the drummer from the device 14, and their subsequent excavation and loading in vehicles with small auxiliary excavating device 15 of the universal unit 4, which allows deriving the rock mass along the straight, curved and combined paths.
Thus, using the generic unit is provided with high quality, selective and controlled loosening raznopolosnyh and different rocks, preserving their original position in the array, enabling high performance, high quality and deeply differentiated excavation of the rock mass.
The claimed method of loosening raznopolosnyh rocks provides a reduction of the major capital and operating costs, improving the efficiency of loosening of rocks and the development of solid mineral deposits in General, as well as various construction works.
The universal unit 4 energy is carried out using diesel-electric installation of the 16 universal unit 4, which can work both autonomously and from any power grid.
The method can be used for open development of ore, rock, coal and gravel deposits, and deposits of construction rocks and construction materials, and in particular, in the development of gold deposits TAS-Yuryakh, Khakanjinskoye and Yuryev, coal deposits - Urgalskoe, Tataurovskoe, Apsatskoe, which are characterized by significant intermittency and inclusions raznopolosnyh rocks, requiring preliminary loosening.
Sources of information
1. Open pit mining. The Handbook. M: Mining, 1994.
2. Rzhevsky CENTURIES Processes of surface mining. M.: Nedra, 1978, 543 S.
3. Patent RU NO. 2039253, E 21 37/00.
4. Patent RU NO. 2181834, E 21 41/00.
5. The fracture energy of the compressed high pressure air. M.: Publishing house of the Institute of mining them. Ass.
Method of loosening raznopolosnyh rocks, including obtaining information about the main structural strength properties of all types of rocks mA is Siwa, detailed zoning of rocks within working operating horizon or its individual plot, the allocation of operational blocks and borders - the elementary units represented by homogeneous fortress rocks, forming a computer program, loosening raznopolosnyh rocks, auxiliary excavation the excavation and loading of the rock mass in small volumes, characterized in that the loosening raznopolosnyh rock field or array construction soils carried out selectively in accordance with their structural strength properties, which distinguish the elementary blocks, using the most effective way is one of mechanical or pneumatic or explosive or physical implemented in an automated process mode using a computer program universal mobile unit, with a dense and relatively weak half-rock breed loosen mechanically with the use of technical devices, equipped with one, two or three teeth on traditional type mounted Ripper, any device with plate metal pins, introduced in the rock by hydraulic cylinders or devices for the formation of holes in the array of elementary block iodrive rock elements from the array block their rasklinivanie, relatively strong half-rocks and hard rocks of medium strength and destroy using the power of compressed air, strong half-rocks and hard rocks elementary blocks destroy the drilling and blasting method, and wells or bore-holes with a diameter of 16-150 mm Buryats rotary or rotary-percussion or percussion-rotary or combined method, blow up the bore-holes and wells of small diameter of the detonating cord or patronized nizkobyudzhetnym explosive, a small diameter cartridge or natronomonas nizkobyudzhetnym explosive, descobrindo explosive mixture initiate laser pulse, the blasting is performed under local shelter mobile unit, small inclusions of rocks, as well as the oversized destroy mechanical shock, while the excavation and loading of the rock mass produce auxiliary excavation device, and the execution of all processes and operations associated with loosening raznopolosnyh rocks, manufactured using universal mobile unit that includes a complex variety of devices to implement mechanical way of loosening of rocks, wells and bore-holes, loading and blasting, laser system initiation, computer system, eliminate the STV for the destruction of rocks by the energy of compressed air and blow, device for supporting excavations excavation of the rock mass in small amounts.
FIELD: mining industry, particularly for open-cut steeply dipping or inclined deposit development.
SUBSTANCE: method involves excavating pit up to design depth reaching by sliced benches; moving the benches as ore deposit is developed; cutting ore and debris; loading thereof on conveyance means to move ore to ground surface, wherein as pit is deepened conveyer systems are used; on reaching the design pit depth deposit is divided into slices and the slices are developed with minimal ore losses in triangular zones with negligible interaction in peripheral face by developed slot raise technology usage; reinforcing slopes with anchors and metal mesh at deep horizons where berm cleaning is difficult; performing slice cutting though the full ore body thickness at design pit bottom and conveying the cut ore to surface by steeply inclined conveyers and combined transportation means. In the case of ore development in slices having lesser thickness below pit bottom steeply dipping and vertical side part are built, concrete wall and metal mesh adapted to hold wedge-like lumps in the presence of potential caving, wherein in this case mining equipment is used and ore cut from underground layer is crushed in crushing mills located on main loading and transportation horizons and delivered to ground surface by conveyer or skip shaft. Mined-out space is filled with rock refuse at terminal stage.
EFFECT: increased efficiency of mineral extraction, reduced cost of deposit development.
8 dwg, 1 ex
FIELD: mining industry.
SUBSTANCE: device has screw, having transporting spiral ribbon held on the shaft. Equipment is provided with U-shaped chute and perforated drum with armature in form of screw ribbon, having curvilinear shape in cross-section, arched in the direction of movement. Drum is mounted in upper portion of U-shaped chute. In its lower portion a screw is mounted.
EFFECT: higher productiveness.
FIELD: mining industry and building, particularly methods or devices for rock dislodging.
SUBSTANCE: method involves creating weakened areas in material; sealing the weakened area; pumping pressurized working agent into weakened material. Before weakened area forming at least two holes are drilled in the material so that holes reach plane of further material breaking. At least three heating members are arranged in the holes along weakened area perimeter. Weakened area creation is performed in area of following material breaking by local material heating to form crack between adjacent holes. Working agent pumping is performed until crack reaches free surface. Distance between adjacent holes is not less than 0.1 m and is not more than 1.2 m. Material is heated up to temperature of not more than 1200°C. Gas or liquid or superheated vapor obtained during liquid feeding to local heated zone of the material or explosive gas may be used as the working agent. Material is heated by means of electric heaters or by thermit mixture.
EFFECT: increased accuracy of crack orientation.
10 cl, 4 dwg
FIELD: mining, particularly to cut oversized pieces, break building structures, cut blocks from rock massifs, produce building stone and crystalline stock material.
SUBSTANCE: method involves drilling boreholes; supplying Newtonian liquid poured in shells made of elastic-plastic material; arranging wedges in the boreholes and applying periodical impact load to wedges.
EFFECT: increased ability of borehole filling with Newtonian liquid without air pocket formation, reduced influence of accidental cracks and weakening planes on direction of crack to be formed.
4 cl, 4 dwg
FIELD: mining and building, particularly control methods for hydraulic driven pulse systems, to design hydraulic percussion machines.
SUBSTANCE: method involves permanently connecting return stroke chamber to system comprising liquid source and accumulator; connecting forward stroke chamber alternately to liquid source or to drain means adapted to discharge liquid into vessel through hydraulic distribution means including the first and the second control chambers, wherein forward stroke chamber is connected to liquid source in response to a control signal which controls striker shifting into forward stroke, and forward stroke chamber is connected to drain means in response to a control signal which controls striker shifting into return stroke after striker fixation; exerting permanent additional force upon the second control chamber connected to upper striker location sensor. Above alternate connection between forward stroke chamber and liquid source or drain means is carried out by means of quick-acting valve connected to liquid source, to drain means and to the first chamber of hydraulic distribution means. Above control signals for striker shifting into forward or return strokes are transmitted to quick-acting valve from control unit. Time delays for control signal transmission are set manually or with the use of control unit to provide quick-acting valve shifting relative synchronization moment set by timing sensor in accordance to operation condition sensor signal magnitude.
EFFECT: increased efficiency and operational reliability.
2 cl, 1 dwg
FIELD: mining, particularly hand tools or hand-held power-operated tools specially adapted for dislodging minerals.
SUBSTANCE: pneumatic hammer has body with radial outlet channel and central channel, lid with annular shoulder and central orifice supported by body end in air-tight manner, striker with through axial channel dividing central body channel into working and idle stroke chambers, tube having blind shoulder arranged from lid side, longitudinal and radial channels. The tube is installed coaxially in central body channel and cooperates with through axial channel of the striker and with central lid orifice by side wall thereof so that annular dap is created between tube and lid. The annular gap may be closed with blind lid shoulder. Hammer has cup, which is air-tightly installed relative annular shoulder and body so that annular accumulation chamber is formed between side cup surface and lid. Annular accumulation chamber is permanently communicated with idle stroke chamber by radial bypass channel in the body. Annular lid shoulder and cup with air inlet channel define prechamber. Air inlet channel permanently communicate prechamber with compressed air system through air hose and nipple releasable connected to the cup. Hammer comprises ring with outlet orifices forming outlet chamber between the body and outlet channel, executive tool with shank and shoulder cooperating with body end and with shank cooperating with hammer, cap with annular shock absorber retaining executive tool from falling out of central body channel. Executive tool shank is provided with central blind hole for receiving tube rested upon bottom thereof. Side surfaces of the tube and central blind hole cooperate to define annular channel having throat, which is not less than that of longitudinal tube channel.
EFFECT: increased operational reliability and power of hammer stroke.
FIELD: mining, particularly hand tools or hand-held power-operated tools specially adapted for dislodging minerals.
SUBSTANCE: pneumatic hammer comprises arm with cup, executive tool, body with outlet channel closed with lid from arm side and defining annular prechamber for system air between cup and lid, working and idle stroke chambers, displacement chamber located between lid and larger body step and pressurizing chamber defined by recess with cut-off edges permanently formed on inner side surface of central stepped channel by annular prechamber communicated with compressed air system. Hammer also has inlet throttle channel formed in pressurizing chamber wall, annular neck portion located in central stepped lid channel between pressurizing and displacement chambers, bypass displacing channel having radial outlet formed in the body and communicating with working stroke chamber arranged between pressurizing chamber and outlet channel formed in the body and striker with upper and lower cut-off edges located in central stepped channel along body axis. Distance between the striker edges is greater than distance between displacement chamber outlet and cutoff edge of larger central channel step. Hammer is additionally provided with inlet throttle channel made in the lid and permanently communicated with annular prechamber. Radial bypass displacing channel inlet is formed in the annular neck portion between pressurizing and displacing chambers from displacing chamber side so that distance between cut-off edges of displacing chamber on side central stepped body channel surface is greater than distance between cut-off striker edges.
EFFECT: increased power of hammer stroke.
FIELD: dislodging equipment for cutting rock, artificial frangible materials, for loosening frozen ground and for compacting fill-up soil, particularly replaceable tool adapted to be connected to shovel boom and operative tool of fixed high-strength rock dislodging plant.
SUBSTANCE: device has resilient seals, hydropneumatic accumulator piston movably installed in device body and comprising cylindrical shaft connected to piston end facing hydraulic chamber thereof and mating device body. Cylindrical shaft has annular groove formed in medium part thereof and brings end chamber of distribution means having larger diameter into communication with draining pipeline or with working liquid source through body channels. End chamber having lesser diameter permanently communicates with working liquid source. Rear cavity of working stroke chamber located behind working end of percussion piston communicates with working liquid source or with working stroke chamber through body channels and two check valves.
EFFECT: increased efficiency, simplicity and reliability, reduced cost and size, improved manufacturability, prevention of working fluid flow between working stroke chamber and idle stroke chamber, increased impact frequency with a given pump capacity and impact energy.
2 cl, 1 dwg
FIELD: mining industry, particularly devices for drilling and reaming wells in hard rock.
SUBSTANCE: drilling device has drilling tool made as boring rod with rock-cutting members and flame-jet burner installed at end thereof. Device also comprises pipelines for supplying fuel, water and air from discharge compressor outlet to flame-jet burner, as well as compressor with filter arranged at suction pipe inlet. Filter comprises body with condensate-tapper, converging nozzle and deflector. Flame-jet burner is made as a plurality of nozzles. Number of burner nozzles is divisible by 2. Each nozzle has curvilinear grooves extending from inlet orifice to outlet one in longitudinal direction. Curvature of groove generatrix of one nozzle advances in clockwise direction. Curvature of groove generatrix of another nozzle advances in counterclockwise direction.
EFFECT: reduced power inputs due to improved parameters of temperature fields and fields of stresses in well body where high-temperature fuel combustion processes cooperate with rock of complex structure and texture.
FIELD: mining industry.
SUBSTANCE: device has hollow cylindrical body with radial apertures and ring-shaped shelves at the ends and self-compacting collars. These are mounted on opposite ends of body and are adjacent by bases to its ring-shaped shelves. On the latter barrels are fitted with central apertures in bases. Through barrels and body a pipe is let with possible longitudinal displacement relatively to body, having radial apertures, ring-shaped shelf at one end and outer thread at other end. Pipe is pressurized on the side of ring-shaped shelf, its radial apertures are in zone of radial apertures of body, one barrel is stopped against ring-shaped shelf of pipe, and other barrel is connected to pipe by threaded connection.
EFFECT: higher efficiency.
FIELD: mining industry, particularly use of explosive substances based on calcium oxide for developing decorative rock, for safe breaking building structures and objects taken out of service.
SUBSTANCE: method involves reducing limestone to powder state, mixing powder with fine solid fuel; granulating thereof; high-temperature roasting the obtained granules in bed by penetration method under temperature of not less than 1500°C; grinding roasted granules to obtain the following fractional composition (% by weight): particles with 0.1 mm or lesser size- 30-50, particles with 0.1-0.25 mm size - 25-40, particles with 0.25-0.5 mm size - 15-25, particles with 0.5 mm and greater size - up to 20. To provide increased expansion clinker binding agent, for instance Portland cement taken in amount of 10-30% of roasted product mass is added to roasted granules.
EFFECT: improved quality, increased inner friction of hardening mix, provision of breaking force exceeding 180 MPa and 1.5-2 fold cost reduction in comparison with prior art method using rotary furnaces.
2 cl, 1 tbl
SUBSTANCE: device has impact assembly, support for fixing impact assembly, pneumatic tanks, mounted between impact assembly and support. Pneumatic tanks are interconnected constantly by air-conducting sleeve. One of tanks is connected to compressed air source by air-conductive sleeve, containing adjusting device for changing rigidity of tanks dependent on changes in physical-mechanical properties of destructed object.
EFFECT: higher reliability.
FIELD: mining industry, construction, mechanical engineering, etc.
SUBSTANCE: machine includes barrel made of impact and static sections, mounted telescopically one in another with possible axial displacement, excluding axial impaction thereof to each other, while both sections are placed in resilient body, made of elastomer, and body has inner bead formed by coaxial recesses of greater and lesser diameters, while impact section is placed in recess of lesser diameter on the outer side of body, and static section is placed in body recess of greater diameter and has outer bead for interaction with appropriate inner bead of body, and also has longitudinal grooves on outer surface, made along forming lines, portion of which by radial drain ports near inner end of barrel are connected to straight drive chamber, and second part connected to back flow chamber by drain ports near outer end of barrel, below-valve and above-valve saddles, respectively covers for barrel and valve box, are made in form of straight and reversed cones, and valve is made of elastic polymer in form of two-tab construction, tabs of which consist of two hollow truncated cones, rigidly interconnected by bases, with forming of chamber, conical on both sides, and outer conical surfaces of upper and lower tabs match conical surfaces of respectively above-valve and below-valve saddles and interact with them in turns, impact mechanism is made of two masses serially placed in barrel - striker and piston, having spherical ends for interaction with forming of intermediate chamber between them, working implement holder lid, fixed on outer end of body, made of elastomer, has a recess in form of inner cone inside ring-shaped edge for interaction with appropriate outer cone on body and pass aperture in base near center, diameter of which matches diameter of bead on replaceable implement, holder of working implement is made of shockproof elastomer in form of cut bushing, having a bead outside for interaction with bottom inside lid and a cylindrical portion, diameter of which matches diameter of pass valve in lid, in which it is mounted, and inner holder diameter matches diameter of neck of replaceable working implement.
EFFECT: higher efficiency, lower vibration, higher effectiveness.