E21D1/00	7	Sinking shafts	E21D1/00	E21D1/00		265
E21D1/02	8	by hand	E21D1/02	E21D1/02		7
E21D1/03	8	mechanically, {e.g. by loading shovels or loading buckets, scraping devices, conveying screws}(E21D1/08 takes precedence)	E21D1/03	E21D1/03		424
E21D1/04	9	with grabs {(boring grabs E21D1/04, E21B27/00; grab buckets for digging in general E02F3/47)}	E21D1/04	E21D1/04		81
E21D1/06	9	with shaft-boring cutters (drilling machines E21B, E21C)	E21D1/06	E21D1/06		502
E21D1/08	8	while moving the lining downwards {(lowering the lining into a ready shaft E21D5/01; sheet piles E02D5/02)}	E21D1/08	E21D1/08		243
E21D1/10	8	Preparation of the ground {(for galleries or tunnels E21D9/001; improving or preserving foundation soil or rock E02D3/00)}	E21D1/10	E21D1/10		50
E21D1/105	9	{by water level modification}	E21D1/10	E21D1/10		24
E21D1/12	9	by freezing {(freezing of foundation soil E02D3/115)}	E21D1/12	E21D1/12		182
E21D1/14	10	Freezing apparatus	E21D1/14	E21D1/14		90
E21D1/16	9	by petrification (grouting anchoring-bolts E21D20/02{; consolidating foundation soil by placing solidifying or pore-filling substances in the soil E02D3/12})	E21D1/16	E21D1/16		123
E21D3/00	7	Raising shafts, i.e. working upwards from the bottom	E21D3/00	E21D3/00		199
E21D5/00	7	Lining shafts; Linings therefor (E21D11/00 takes precedence {; sinking with simultaneous lowering of the lining E21D1/08})	E21D5/00	E21D5/00		159
E21D5/01	8	using prefabricated lining lowered into a hole filled with liquid or viscous mass	E21D5/01	E21D5/01		51
E21D5/012	8	Use of fluid-tight or anti-friction material on outside of, or between, lining layers	E21D5/012	E21D5/012		128
E21D5/016	8	Bearer curbs	E21D5/016	E21D5/016		20
E21D5/02	8	with wood (E21D5/01, E21D5/012, E21D5/016 take precedence)	E21D5/02	E21D5/02		3
E21D5/04	8	with brick, concrete, stone, or similar building materials (E21D5/01, E21D5/012, E21D5/016 take precedence)	E21D5/04	E21D5/04		648
E21D5/06	8	with iron or steel (E21D5/01, E21D5/012, E21D5/016 take precedence)	E21D5/06	E21D5/06		138
E21D5/08	9	in the form of profiled parts	E21D5/08	E21D5/08		73
E21D5/10	9	in the form of tubbing {or of rings composed of profile elements}	E21D5/10	E21D5/10		125
E21D5/11	8	with combinations of different materials, e.g. wood, metal, concrete (E21D5/01, E21D5/012, E21D5/016 take precedence)	E21D5/11	E21D5/11		465
E21D5/12	8	Accessories for making shaft linings, e.g. suspended cradles, shutterings	E21D5/12	E21D5/12		625
E21D7/00	7	Shaft equipment, e.g. timbering within the shaft {(lifts in hoistways or mines B66B15/00&#160;-&#160;B66B19/00)}	E21D7/00	E21D7/00		619
E21D7/005	8	{Determination of shaft lining deformation}	E21D7/00	E21D7/00		17
E21D7/02	8	Arrangement of guides for cages in shafts; Connection of guides for cages to shaft walls (guideways or guides for elevators B66B7/02)	E21D7/02	E21D7/02		186
E21D8/00	7	Shafts not provided for in groups E21D1/00&#160;-&#160;E21D7/00	E21D8/00	E21D8/00		178
E21D9/00	7	Tunnels or galleries, with or without linings; Methods or apparatus for making thereof (E02D29/045, E02D29/063 take precedence; linings per seE21D11/00); Layout of tunnels or galleries	E21D9/00	E21D9/00		2833
E21D9/001	8	{Improving soil or rock, e.g. by freezing; Injections (for sinking shafts E21D1/10; injection of liquids for binding dust E21F5/18; improving or preserving foundation soil or rock E02D3/00; borehole closures, i.e. packers, for use during the injection process E21B33/12)}	E21D9/00	E21D9/00		2352
E21D9/002	9	{Injection methods characterised by the chemical composition used}	E21D9/00	E21D9/00		326
E21D9/003	8	{Arrangement of measuring or indicating devices for use during driving of tunnels, e.g. for guiding machines}	E21D9/00	E21D9/00		1832
E21D9/004	9	{using light beams for direction or position control}	E21D9/00	E21D9/00		215
E21D9/005	8	{by forcing prefabricated elements through the ground, e.g. by pushing lining from an access pit (driving shields E21D9/06)}	E21D9/00	E21D9/00		870
E21D9/006	8	{by making use of blasting methods (explosive compositions C06B; blasting per seF42)}	E21D9/00	E21D9/00		1772
E21D9/008	8	{Driving transverse tunnels starting from existing tunnels}	E21D9/00	E21D9/00		170
E21D9/01	8	Methods or apparatus for enlarging or restoring the cross-section of tunnels, e.g. by restoring the floor to its original level	E21D9/01	E21D9/01		504
E21D9/02	8	Driving inclined tunnels or galleries	E21D9/02	E21D9/02		302
E21D9/03	8	{Driving non-circular tunnels}	E21D9/00	E21D9/03		141
E21D9/04	8	Driving tunnels or galleries through loose materials; Apparatus therefor not otherwise provided for {(E21D9/005, E21D9/06 take precedence; soil improvement E21D9/001; provisional protective covers E21D19/04)}	E21D9/04	E21D9/04		668
E21D9/06	8	Making by using a driving shield {, i.e. advanced by pushing means bearing against the already placed lining (pushing prefabricated elements through the ground from an access pit E21D9/005)}	E21D9/06	E21D9/06		3346
E21D9/0607	9	{the shield being provided with devices for lining the tunnel, e.g. shuttering (E21D9/0873, E21D9/0879 take precedence; tail sealing means used as end shuttering E21D9/0635)}	E21D9/06	E21D9/06		1286
E21D9/0609	10	{with means for applying a continuous liner, e.g. sheets of plastics, between the main concrete lining and the rock}	E21D9/06	E21D9/06		204
E21D9/0621	9	{Shield advancing devices}	E21D9/06	E21D9/06		885
E21D9/0635	9	{Tail sealing means, e.g. used as end shuttering}	E21D9/06	E21D9/06		474
E21D9/0642	9	{the shield having means for additional processing at the front end}	E21D9/06	E21D9/06		419
E21D9/065	10	{with devices for provisionally supporting the front face}	E21D9/06	E21D9/06		104
E21D9/0657	10	{structurally associated with rock crushers}	E21D9/06	E21D9/06		103
E21D9/0664	10	{with means for applying a coating layer to the front face, e.g. by spraying}	E21D9/06	E21D9/06		43
E21D9/0671	10	{with means for consolidating the rock in front of the shield by injection of consolidating substances through boreholes}	E21D9/06	E21D9/06		141
E21D9/0678	10	{Adding additives, e.g. chemical compositions, to the slurry or the cuttings}<br><br><u>NOTE</u><br><br>When classifying in this group, bentonite shall not be classified	E21D9/06	E21D9/06		245
E21D9/0685	11	{Foaming agents}	E21D9/06	E21D9/06		70
E21D9/0692	9	{Cutter drive shields}	E21D9/06	E21D9/06		353
E21D9/08	9	with additional boring or cutting means {other than the conventional cutting edge of the shield}	E21D9/08	E21D9/08		2014
E21D9/087	10	with a rotary drilling-head cutting simultaneously the whole cross-section, i.e. full-face machines	E21D9/087	E21D9/087		1011
E21D9/0873	11	{the shield being provided with devices for lining the tunnel, e.g. shuttering}	E21D9/087	E21D9/087		347
E21D9/0874	10	{with rotary drilling heads having variable diameter}	E21D9/08	E21D9/087		76
E21D9/0875	10	{with a movable support arm carrying cutting tools for attacking the front face, e.g. a bucket}	E21D9/08	E21D9/087		134
E21D9/0879	11	{the shield being provided with devices for lining the tunnel, e.g. shuttering}	E21D9/08	E21D9/087		502
E21D9/093	9	Control of the driving shield {, e.g. of the hydraulic advancing cylinders (arrangement of measuring or indicating devices for use during driving of tunnels E21D9/003)}	E21D9/093	E21D9/093		1080
E21D9/10	8	Making by using boring or cutting machines (E21D9/08 takes precedence; mining picks E21C35/18)	E21D9/10	E21D9/10		2070
E21D9/1006	9	{with rotary cutting tools (for cutting simultaneously the whole cross-section E21D9/11; drill bits E21B10/00)}	E21D9/10	E21D9/10		1121
E21D9/1013	10	{on a tool-carrier supported by a movable boom}	E21D9/10	E21D9/10		177
E21D9/102	11	{by a longitudinally extending boom being pivotable about a vertical and a transverse axis}	E21D9/10	E21D9/10		152
E21D9/1026	12	{the tool-carrier being rotated about a transverse axis}	E21D9/10	E21D9/10		162
E21D9/1033	11	{by a transversely extending boom being pivotable about a longitudinal axis}	E21D9/10	E21D9/10		81
E21D9/104	10	{Cutting tool fixtures (devices with percussive tools E21D9/106)}	E21D9/10	E21D9/10		338
E21D9/1046	11	{Vibrating}	E21D9/10	E21D9/10		43
E21D9/1053	9	{for making a slit along the perimeter of the tunnel profile, the remaining core being removed subsequently, e.g. by blasting}	E21D9/10	E21D9/10		213
E21D9/106	9	{with percussive tools, e.g. pick-hammers}	E21D9/10	E21D9/10		357
E21D9/1066	9	{with fluid jets (projecting hot gases E21D9/1073; drilling by liquid or gas jets E21B7/18; slitting by liquid jets E21C25/60)}	E21D9/10	E21D9/10		388
E21D9/1073	9	{applying thermal energy, e.g. by projecting flames or hot gases, by laser beams (flame drilling E21B7/14)}	E21D9/10	E21D9/10		147
E21D9/108	9	{Remote control specially adapted for machines for driving tunnels or galleries (for machines for slitting or completely freeing the mineral E21C35/24)}	E21D9/10	E21D9/10		419
E21D9/1086	9	{Drives or transmissions specially adapted therefor}	E21D9/10	E21D9/10		761
E21D9/1093	9	{Devices for supporting, advancing or orientating the machine or the tool-carrier (measuring devices for guiding machines E21D9/003; anchoring in the borehole E21B4/18)}	E21D9/10	E21D9/10		1114
E21D9/11	9	with a rotary drilling-head cutting simultaneously the whole cross-section, i.e. full-face machines	E21D9/11	E21D9/11		711
E21D9/111	10	{by means of heads or tool-carrying sectors implementing an oscillating rotary motion}	E21D9/11	E21D9/11		18
E21D9/112	10	{by means of one single rotary head or of concentric rotary heads (E21D9/111 takes precedence)}	E21D9/11	E21D9/11		304
E21D9/113	11	{having a central part for making a pilot tunnel and a follow-up part for enlarging the pilot tunnel (E21D9/115 takes precedence; similar apparatus for enlarging drilled boreholes E21B7/28)}	E21D9/11	E21D9/11		57
E21D9/115	11	{with cutting tools mounted pivotably or slidable on the head}	E21D9/11	E21D9/11		63
E21D9/116	10	{by means of non-concentric rotary heads (E21D9/111 takes precedence)}	E21D9/11	E21D9/11		132
E21D9/117	11	{mounted for orientating or sideways shifting relative to the frame}	E21D9/11	E21D9/11		34
E21D9/118	11	{with independently driven central head}	E21D9/11	E21D9/11		18
E21D9/12	8	Devices for removing or hauling away excavated material or spoil; Working or loading platforms (underground transport E21F13/00)	E21D9/12	E21D9/12		2198
E21D9/122	9	{Working or loading platforms (underground transport E21F13/00)}	E21D9/12	E21D9/12		535
E21D9/124	9	{Helical conveying means therefor (E21D9/13 takes precedence)}	E21D9/12	E21D9/12		708
E21D9/126	9	{Loading devices or installations (loading platforms E21D9/122; soil-shifting machines E02F3/00)}	E21D9/12	E21D9/12		557
E21D9/128	10	{Loader-conveyors with gathering arms}	E21D9/12	E21D9/12		303
E21D9/13	9	using hydraulic or pneumatic conveying means	E21D9/13	E21D9/13		366
E21D9/14	8	Layout of tunnels or galleries; Constructional features of tunnels or galleries, not otherwise provided for, e.g. portals, day-light attenuation at tunnel openings	E21D9/14	E21D9/14		2659
E21D11/00	7	Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling (E21D15/00&#160;-&#160;E21D23/00 take precedence; specially for shafts E21D5/00; {driving shields in combination with means for lining the tunnel E21D9/06}; lining pressure water galleries, linings therefor E02B9/06)	E21D11/00	E21D11/00		2057
E21D11/003	8	{Linings or provisions thereon, specially adapted for traffic tunnels, e.g. with built-in cleaning devices (E21D11/38 takes precedence)}	E21D11/00	E21D11/00		1438
E21D11/006	8	{Lining anchored in the rock (setting anchoring-bolts E21D20/00; anchoring-bolts E21D21/00)}	E21D11/00	E21D11/00		771
E21D11/02	8	Lining predominantly with wood	E21D11/02	E21D11/02		63
E21D11/03	9	using timber- setting machines	E21D11/03	E21D11/03		39
E21D11/04	8	Lining with building materials (E21D11/02, E21D11/14 take precedence {; compositions of mortars, concrete or like building materials C04B; placing filling-up materials in underground workings E21F15/00})	E21D11/04	E21D11/04		429
E21D11/05	9	using compressible insertions	E21D11/05	E21D11/05		232
E21D11/06	9	with bricks	E21D11/06	E21D11/06		71
E21D11/07	10	using brick- laying machines {(brick-laying machines per seE04G21/22)}	E21D11/07	E21D11/07		40
E21D11/08	9	with preformed concrete slabs {(backfilling the space between the slabs and the rock E21D11/105)}	E21D11/08	E21D11/08		3340
E21D11/083	10	{Methods or devices for joining adjacent concrete segments}	E21D11/08	E21D11/08		1337
E21D11/086	10	{Methods of making concrete lining segments}	E21D11/08	E21D11/08		293
E21D11/10	9	with concrete cast in situ; Shuttering {also lost shutterings, e.g. made of blocks, of metal plates} or other equipment adapted therefor	E21D11/10	E21D11/10		8327
E21D11/102	10	{Removable shuttering; Bearing or supporting devices therefor}	E21D11/10	E21D11/10		1991
E21D11/105	10	{Transport or application of concrete specially adapted for the lining of tunnels or galleries (in building E04F21/08, E04G21/02); Backfilling the space between main building element and the surrounding rock, e.g. with concrete}	E21D11/10	E21D11/10		5379
E21D11/107	10	{Reinforcing elements therefor; Holders for the reinforcing elements}	E21D11/10	E21D11/10		1697
E21D11/12	9	Temporary supports for use during building {(removable shutterings E21D11/102)}; Accessories {(provisional protective covers E21D19/04)}	E21D11/12	E21D11/12		326
E21D11/14	8	Lining predominantly with metal {(backfilling the space between the lining elements and the rock E21D11/105)}	E21D11/14	E21D11/14		1269
E21D11/15	9	Plate linings; Laggings, i.e. linings designed for holding back formation material or for transmitting the load to main supporting members (insulation E21D11/38)	E21D11/15	E21D11/15		755
E21D11/152	10	{Laggings made of grids or nettings}	E21D11/15	E21D11/15		1915
E21D11/155	10	{Laggings made of strips, slats, slabs or sheet piles (longitudinal struts for mine arches E21D11/28)}	E21D11/15	E21D11/15		425
E21D11/157	10	{Laggings making use of fluid cushions, e.g. the fluid containing a hardenable material (chocks made of flexible containers E21D15/483)}	E21D11/15	E21D11/15		117
E21D11/18	9	Arch members {; Network made of arch members (E21D11/36 takes precedence); Ring elements; Polygon elements; Polygon elements inside arches (caps for arches E21D17/00)}	E21D11/18	E21D11/18		2950
E21D11/183	10	{Supporting means for arch members, not provided for in E21D11/22}	E21D11/18	E21D11/18		757
E21D11/186	10	{Pre-stressing or dismantling devices therefor}	E21D11/18	E21D11/18		73
E21D11/20	10	Special cross- sections, e.g. corrugated {(for props E21D15/502; for caps E21D17/01)}	E21D11/20	E21D11/20		634
E21D11/22	10	Clamps or other yieldable means for interconnecting adjacent arch members either rigidly, or allowing arch member parts to slide when subjected to excessive pressure	E21D11/22	E21D11/22		1027
E21D11/24	10	Knuckle joints or links between arch members	E21D11/24	E21D11/24		344
E21D11/26	10	Shoes for connecting arch members to longitudinal struts	E21D11/26	E21D11/26		81
E21D11/28	9	Longitudinal struts {, i.e. longitudinal connections between adjoining arches}	E21D11/28	E21D11/28		536
E21D11/30	9	Bases for lower arch members (for props E21D15/54)	E21D11/30	E21D11/30		138
E21D11/34	9	Joints between vertical props and horizontal top bars (end caps forming part of the props E21D15/54{; retaining plates on caps for engaging the tops of pit-props E21D17/10})	E21D11/34	E21D11/34		249
E21D11/36	9	Linings or supports specially shaped for tunnels or galleries of irregular cross-section	E21D11/36	E21D11/36		44
E21D11/362	10	{for loading areas (lining shafts E21D5/00)}	E21D11/36	E21D11/36		4
E21D11/365	10	{for intersecting galleries}	E21D11/36	E21D11/36		51
E21D11/367	10	{for junction with the longwall coal face (walking supports therefor E21D23/0091)}	E21D11/36	E21D11/36		53
E21D11/38	8	Waterproofing (in general E02D31/00); Heat insulating; Soundproofing; Electric insulating (for building constructions in general E04B1/62)	E21D11/38	E21D11/38		3561
E21D11/381	9	{Setting apparatus or devices}	E21D11/38	E21D11/38		798
E21D11/383	9	{by applying waterproof flexible sheets; Means for fixing the sheets to the tunnel or cavity wall}	E21D11/38	E21D11/38		952
E21D11/385	9	{Sealing means positioned between adjacent lining members (for joints in foundation structures E02D29/16; for sewers E03F3/04; for building structures in general E04B1/68)}	E21D11/38	E21D11/38		1026
E21D11/386	10	{inflatable sealing means}	E21D11/38	E21D11/38		199
E21D11/388	10	{having longitudinal cavities communicating with the exterior on the outer side of the lining elements}	E21D11/38	E21D11/38		19
E21D11/40	8	Devices or apparatus specially adapted for handling or placing units of linings {or supporting units} for tunnels or galleries {(combined with tunnelling shields E21D9/06)}	E21D11/40	E21D11/40		2630
E21D11/403	9	{combined with the head machine}	E21D11/40	E21D11/40		97
E21D11/406	9	{Placing endless lining elements, e.g. from reels (in combination with a tunneling shield E21D9/0609)}	E21D11/40	E21D11/40		177
E21D13/00	7	Large underground chambers; Methods or apparatus for making them (lining E21D11/00)	E21D13/00	E21D13/00		723
E21D15/00	7	Props (in the building art E04G25/00); Chocks {, e.g. made of flexible containers filled with backfilling material}	E21D15/00	E21D15/00		193
E21D15/002	8	{Auxiliary devices in which the prop type is not essential (setting or withdrawing props or chocks E21D15/58, E21D15/60)}	E21D15/00	E21D15/00		79
E21D15/005	8	{characterised by the material}	E21D15/00	E21D15/00		165
E21D15/007	9	{spark-reducing}	E21D15/00	E21D15/00		18
E21D15/02	8	Non-telescopic props	E21D15/02	E21D15/02		299
E21D15/04	9	with wooden prop parts joined by double conical connectors	E21D15/04	E21D15/04		19
E21D15/06	9	with parts joined by a lock, with or without slight axial adjustability	E21D15/06	E21D15/06		11
E21D15/08	10	with toggle joint connection	E21D15/08	E21D15/08		22
E21D15/10	10	with dog-clutch or pin-and-hole connection	E21D15/10	E21D15/10		12
E21D15/12	10	with locking devices located near head or foot {(E21D15/08 and E21D15/10 take precedence)}	E21D15/12	E21D15/12		72
E21D15/14	8	Telescopic props (general means for fixing telescopic parts together {F16B7/10})	E21D15/14	E21D15/14		180
E21D15/15	9	Means counteracting entry of dirt; Built-in cleaning devices	E21D15/15	E21D15/15		51
E21D15/155	10	{Built-in cleaning devices}	E21D15/15	E21D15/15		50
E21D15/16	9	with parts held together by positive means, with or without relative sliding movement when the prop is subject to excessive pressure	E21D15/16	E21D15/16		49
E21D15/18	10	with one part resting on a supporting medium, e.g. rubber, sand, bitumen, lead, located in the other part, with or without expulsion or displacement of the medium upon excessive pressure {(clamping pressure between telescopic prop elements by means of granular material E21D15/303)}	E21D15/18	E21D15/18		173
E21D15/20	10	with pawl, pin, cross-piece, or the like engaging with ratchet teeth, notches, holes, or the like, spaced apart at intervals	E21D15/20	E21D15/20		117
E21D15/22	10	with member, pin, cross- piece, or the like, ruptured, sheared through, or permanently deformed upon excessive pressure	E21D15/22	E21D15/22		123
E21D15/24	10	with axial screw-and-nut, rack-and-worm, or like mechanism	E21D15/24	E21D15/24		222
E21D15/26	11	with screw, worm, or the like, not self-locking but normally prevented from rotation by friction members which slip upon excessive pressure	E21D15/26	E21D15/26		52
E21D15/28	9	with parts held relatively to each other by friction or gripping	E21D15/28	E21D15/28		36
E21D15/285	10	{by means of wedges or wedge combinations (details of wedges E21D15/43)}	E21D15/28	E21D15/28		401
E21D15/30	10	by means expanded or contracted by pressure applied through the medium of a fluid or quasi- fluid, e.g. rubber {(setting props E21D15/588, E21D15/589)}	E21D15/30	E21D15/30		19
E21D15/303	11	{by means of granular material (supporting by means of granular material E21D15/18)}	E21D15/30	E21D15/30		23
E21D15/306	11	{by means of a liquid}	E21D15/30	E21D15/30		71
E21D15/32	10	by a deformable collar {or clamping means applied symmetrically inside a locking ring}	E21D15/32	E21D15/32		101
E21D15/325	11	{by a clamping ring}	E21D15/32	E21D15/32		164
E21D15/34	10	by axially- moving balls, rollers, or the like	E21D15/34	E21D15/34		50
E21D15/36	10	by a tiltable collar surrounding one or both parts	E21D15/36	E21D15/36		78
E21D15/38	10	with longitudinally-divided upper or lower prop parts, e.g. interfitting laminations	E21D15/38	E21D15/38		234
E21D15/40	10	Collar or other support gripped to one or both parts by toggle-action, cam, or other member pivoted or similarly mounted	E21D15/40	E21D15/40		129
E21D15/42	10	with special parts to influence the friction	E21D15/42	E21D15/42		128
E21D15/43	10	Details of wedges (friction linings or pads E21D15/42)	E21D15/43	E21D15/43		54
E21D15/435	11	{hydraulic}	E21D15/43	E21D15/43		3
E21D15/44	9	Hydraulic, pneumatic, or hydraulic-pneumatic props {(see also E21D15/51)}	E21D15/44	E21D15/44		1316
E21D15/445	10	{comprising a fluid cushion}	E21D15/44	E21D15/44		30
E21D15/45	10	having closed fluid system, e.g. with built-in pumps or accumulators	E21D15/45	E21D15/45		132
E21D15/46	9	with load-measuring devices; with alarm devices	E21D15/46	E21D15/46		190
E21D15/465	10	{with essential hydraulic or pneumatic details}	E21D15/46	E21D15/46		62
E21D15/48	8	Chocks or the like	E21D15/48	E21D15/48		148
E21D15/483	9	{made of flexible containers, e.g. inflatable, with or without reinforcement, e.g. filled with water, backfilling material or the like (laggings making use of fluid cushions E21D11/157)}	E21D15/48	E21D15/48		161
E21D15/486	9	{with essential hydraulic or pneumatic details}	E21D15/48	E21D15/48		42
E21D15/50	8	Component parts or details of props (E21D15/43, E21D15/58, E21D15/60 take precedence)	E21D15/50	E21D15/50		765
E21D15/502	9	Prop bodies characterised by their shape, e.g. of specified cross-section	E21D15/502	E21D15/502		313
E21D15/51	9	specially adapted to hydraulic, pneumatic, or hydraulic-pneumatic props, e.g. arrangements of relief valves {(not used, see subgroups and E21D15/44)}	E21D15/51	E21D15/51		53
E21D15/512	10	{Arrangement of valves (external control of roof support installations E21D23/12, E21D23/26)}	E21D15/51	E21D15/51		468
E21D15/515	10	{Particular fluids not covered by any chemical subdivision}	E21D15/51	E21D15/51		35
E21D15/517	10	{Extension elements}	E21D15/51	E21D15/51		104
E21D15/52	9	Extensible units located above or below standard props (for allowing step-by-step movement of cap E21D23/06; setting props or chocks E21D15/58)	E21D15/52	E21D15/52		103
E21D15/523	10	{with hydraulic or pneumatic control}	E21D15/52	E21D15/52		47
E21D15/526	10	{for step-by-step extension of the prop}	E21D15/52	E21D15/52		49
E21D15/54	9	Details of the ends of props (for permitting step-by-step movement E21D23/06)	E21D15/54	E21D15/54		398
E21D15/545	10	{hydraulic or pneumatic}	E21D15/54	E21D15/54		49
E21D15/55	10	of prop heads {or feet}	E21D15/55	E21D15/55		500
E21D15/56	9	Details of locks of telescopic props	E21D15/56	E21D15/56		94
E21D15/563	10	{by which a series of similarly shaped props can obtain an almost equal load-capacity (setting props or chocks E21D15/584, E21D15/589)}	E21D15/56	E21D15/56		10
E21D15/566	10	{comprising a fluid cushion}	E21D15/56	E21D15/56		5
E21D15/58	8	Devices for setting props or chocks	E21D15/58	E21D15/58		174
E21D15/581	9	{in which the props are pre- loaded (extensible elements at strut extremities E21D15/52)}	E21D15/58	E21D15/58		205
E21D15/5813	10	{by means of power accumulators to be pre-charged by rock pressure (by means of hydraulically operated devices E21D15/587)}	E21D15/58	E21D15/58		10
E21D15/5817	10	{in which the lock is also activated}	E21D15/58	E21D15/58		33
E21D15/584	9	{in which a series of similarly shaped props obtain an almost equal load capacity by removable devices (idem for extensible props E21D15/563)}	E21D15/58	E21D15/58		20
E21D15/585	9	{by means of hydraulically operated devices for mechanical props, or hydraulic props in which the hydraulic part is not important (hydraulic props in which the hydraulic part is important E21D15/44)}	E21D15/58	E21D15/58		66
E21D15/586	10	{the props being pre-loaded}	E21D15/58	E21D15/58		152
E21D15/587	11	{by means of power accumulators to be pre-charged by rock pressure}	E21D15/58	E21D15/58		32
E21D15/588	11	{the lock also being activated}	E21D15/58	E21D15/58		39
E21D15/589	10	{in which a series of similarly shaped props are given almost equal load capacity by removable devices}	E21D15/58	E21D15/58		24
E21D15/60	8	Devices for withdrawing props or chocks	E21D15/60	E21D15/60		403
E21D15/603	9	{by means of hydraulic devices}	E21D15/60	E21D15/60		63
E21D15/606	9	{the props being moved systematically (mine roof supports for step-by-step movement E21D23/00)}	E21D15/60	E21D15/60		62
E21D17/00	7	Caps for supporting mine roofs	E21D17/00	E21D17/00		319
E21D17/003	8	{with essential hydraulic elements}	E21D17/00	E21D17/00		25
E21D17/006	8	{characterised by the material}	E21D17/00	E21D17/00		47
E21D17/01	8	characterised by the shape of the cap, e.g. of specified cross-section	E21D17/01	E21D17/01		302
E21D17/02	8	Cantilever extension or similar protecting devices	E21D17/02	E21D17/02		57
E21D17/0206	9	{Hydraulically operated extension devices}	E21D17/02	E21D17/02		105
E21D17/0213	9	{Assembling devices for pivoting caps upwardly}	E21D17/02	E21D17/02		74
E21D17/03	9	Brackets for roof-supporting bars	E21D17/03	E21D17/03		99
E21D17/04	9	for use in longwall working	E21D17/04	E21D17/04		53
E21D17/06	9	for use in drifting galleries	E21D17/06	E21D17/06		45
E21D17/08	9	Cap joints for obtaining a coal-face free of pit-props	E21D17/08	E21D17/08		25
E21D17/082	10	of sliding type	E21D17/082	E21D17/082		103
E21D17/086	10	or articulated type	E21D17/086	E21D17/086		432
E21D17/10	8	Details of mine caps for engaging the tops of pit-props, with or without retaining-plates; Retaining-plates	E21D17/10	E21D17/10		278
E21D19/00	7	Provisional protective covers for working space (E21D9/06, E21D23/00 take precedence)	E21D19/00	E21D19/00		673
E21D19/02	8	for use in longwall working	E21D19/02	E21D19/02		278
E21D19/04	8	for use in drifting galleries	E21D19/04	E21D19/04		472
E21D20/00	7	Setting anchoring-bolts (anchoring bolts for shafts, tunnels or galleries E21D21/00; means for anchoring structural elements or bulkheads specially adapted to foundation engineering E02D5/74; dowels or other devices fastened in walls or the like by inserting them in holes made therein for that purpose F16B13/00)	E21D20/00	E21D20/00		2880
E21D20/003	8	{Machines for drilling anchor holes and setting anchor bolts}	E21D20/00	E21D20/00		2947
E21D20/006	9	{having magazines for storing and feeding anchoring-bolts (combined feeding from racks and connecting of drill rods or the like E21B19/20)}	E21D20/00	E21D20/00		235
E21D20/02	8	with provisions for grouting	E21D20/02	E21D20/02		2061
E21D20/021	9	{Grouting with inorganic components, e.g. cement}	E21D20/02	E21D20/02		928
E21D20/023	10	{Cartridges; Grouting charges}	E21D20/02	E21D20/02		81
E21D20/025	9	{Grouting with organic components, e.g. resin}	E21D20/02	E21D20/02		702
E21D20/026	10	{Cartridges; Grouting charges}	E21D20/02	E21D20/02		266
E21D20/028	9	{Devices or accesories for injecting a grouting liquid in a bore-hole (E21D20/003 takes precedence; improving soil or rock by injections E21D9/001)}	E21D20/02	E21D20/02		887
E21D21/00	7	Anchoring-bolts for roof, floor {in galleries or longwall working}, or shaft-lining protection ({ground anchors E02D5/80; anchorings for building constructions E04B1/41, E21D21/00}; dowels or other devices fastened in walls or the like by inserting them in holes made therein for that purpose F16B13/00{; bolts with visible load G01L1/00})	E21D21/00	E21D21/00		995
E21D21/0006	8	{characterised by the bolt material}	E21D21/00	E21D21/00		411
E21D21/0013	8	{Protection against corrosion}	E21D21/00	E21D21/00		117
E21D21/002	8	{using explosives charges}	E21D21/00	E21D21/00		33
E21D21/0026	8	{characterised by constructional features of the bolts}	E21D21/00	E21D21/00		2710
E21D21/0033	9	{having a jacket or outer tube}	E21D21/00	E21D21/00		598
E21D21/004	9	{Bolts held in the borehole by friction all along their length, without additional fixing means}	E21D21/00	E21D21/00		240
E21D21/0046	9	{formed by a plurality of elements arranged longitudinally}	E21D21/00	E21D21/00		341
E21D21/0053	9	{Anchoring-bolts in the form of lost drilling rods}	E21D21/00	E21D21/00		239
E21D21/006	9	{Anchoring-bolts made of cables or wires}	E21D21/00	E21D21/00		433
E21D21/0066	9	{Anchoring-bolts formed by a bundle of radially arranged rigid elements}	E21D21/00	E21D21/00		55
E21D21/0073	9	{Anchoring-bolts having an inflatable sleeve, e.g. hollow sleeve expanded by a fluid}	E21D21/00	E21D21/00		199
E21D21/008	8	{Anchoring or tensioning means}	E21D21/00	E21D21/00		1819
E21D21/0086	8	{Bearing plates}	E21D21/00	E21D21/00		492
E21D21/0093	8	{Accessories}	E21D21/00	E21D21/00		1348
E21D21/02	8	having means for indicating tension (screwed connections specially modified for indicating tensile load F16B31/02)	E21D21/02	E21D21/02		439
E21D23/00	7	Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor ({transport of mine roof support units E21F13/008; } shifting of mine conveyors at the working face E21F13/08)	E21D23/00	E21D23/00		331
E21D23/0004	8	{along the working face}	E21D23/00	E21D23/00		365
E21D23/0008	9	{comprising a pair of joined struts}	E21D23/00	E21D23/00		31
E21D23/0013	9	{Frame type supports}	E21D23/00	E21D23/00		91
E21D23/0017	9	{Pile type supports}	E21D23/00	E21D23/00		112
E21D23/0021	10	{comprising two walking elements}	E21D23/00	E21D23/00		56
E21D23/0026	10	{comprising three walking elements}	E21D23/00	E21D23/00		19
E21D23/003	10	{consisting of a rigid pile}	E21D23/00	E21D23/00		29
E21D23/0034	9	{comprising a goaf shield articulated to a base member}	E21D23/00	E21D23/00		194
E21D23/0039	10	{and supported by a strut or by a row of struts parallel to the working face}	E21D23/00	E21D23/00		96
E21D23/0043	10	{and supported by two or more rows of struts parallel to the working face}	E21D23/00	E21D23/00		78
E21D23/0047	8	{without essential shifting devices}	E21D23/00	E21D23/00		195
E21D23/0052	8	{with advancing shifting devices connected therewith}	E21D23/00	E21D23/00		566
E21D23/0056	8	{with individual advancing shifting devices}	E21D23/00	E21D23/00		113
E21D23/006	8	{provided with essential hydraulic devices}	E21D23/00	E21D23/00		96
E21D23/0065	9	{driven, or automatically, e.g. electrically-hydraulically controlled}	E21D23/00	E21D23/00		87
E21D23/0069	9	{without essential advancing shifting devices}	E21D23/00	E21D23/00		147
E21D23/0073	9	{with advancing shifting devices connected therewith}	E21D23/00	E21D23/00		157
E21D23/0078	9	{with individual shifting devices}	E21D23/00	E21D23/00		24
E21D23/0082	8	{specially adapted for vertical or steep gradient seams}	E21D23/00	E21D23/00		64
E21D23/0086	8	{in galleries}	E21D23/00	E21D23/00		85
E21D23/0091	9	{at the junction with the working face}	E21D23/00	E21D23/00		61
E21D23/0095	9	{Temporary supports at the driving front}	E21D23/00	E21D23/00		116
E21D23/03	8	having protective means, e.g. shields, for preventing or impeding entry of loose material into the working space or support	E21D23/03	E21D23/03		439
E21D23/04	8	Structural features of the supporting construction, e.g. linking members between adjacent frames or sets of props; Means for counteracting lateral sliding on inclined floor (E21D23/14 takes precedence)	E21D23/04	E21D23/04		1710
E21D23/0409	9	{Aligning or guiding means for the supports or for the constitutive parts of the supports}	E21D23/04	E21D23/04		574
E21D23/0418	9	{Positioning devices and stabilizing means for the props}	E21D23/04	E21D23/04		250
E21D23/0427	9	{Shield operating devices; Hinges therefor}	E21D23/04	E21D23/04		135
E21D23/0436	9	{Means for inclining the base member of the support}	E21D23/04	E21D23/04		54
E21D23/0445	9	{Extensions of the base member supporting the conveyor}	E21D23/04	E21D23/04		30
E21D23/0454	9	{Trailing plates; Coal face or goaf side sprags (specially adapted for the placing of filling-up materials E21D23/0481)}	E21D23/04	E21D23/04		86
E21D23/0463	9	{Hanging or shifting means for tubes, electric feeding cables or the like}	E21D23/04	E21D23/04		41
E21D23/0472	9	{Supports specially adapted for people walking or transporting material}	E21D23/04	E21D23/04		98
E21D23/0481	9	{Supports specially adapted for use in combination with the placing of filling-up materials (placing filling-up materials in underground workings per seE21F15/00)}	E21D23/04	E21D23/04		236
E21D23/049	9	{Connecting devices between the head or foot of a prop and the cap or base of the roof support}	E21D23/04	E21D23/04		62
E21D23/06	9	Special mine caps or special tops of pit-props for permitting step-by-step movement	E21D23/06	E21D23/06		485
E21D23/063	10	{Retractable cantilever extensions therefor}	E21D23/06	E21D23/06		115
E21D23/066	10	{Pivoted cantilever extensions therefor}	E21D23/06	E21D23/06		91
E21D23/08	8	Advancing mechanisms (E21D23/16 takes precedence)	E21D23/08	E21D23/08		382
E21D23/081	9	{forming parts of the roof supports}	E21D23/08	E21D23/08		120
E21D23/082	10	{acting solely on the elements of the supports}	E21D23/08	E21D23/08		45
E21D23/083	10	{acting on a firm abutment adapted thereto}	E21D23/08	E21D23/08		16
E21D23/085	10	{acting on a conveyor or a guide for the mining machine}	E21D23/08	E21D23/08		113
E21D23/086	11	{Details of fixing devices therefor}	E21D23/08	E21D23/08		46
E21D23/087	10	{acting directly on the walls of the seam}	E21D23/08	E21D23/08		5
E21D23/088	11	{by means of wheels, rollers, caterpillars, belts or worm screws}	E21D23/08	E21D23/08		61
E21D23/10	9	with advancing devices separate from the supporting construction	E21D23/10	E21D23/10		85
E21D23/12	8	Control, e.g. using remote control (E21D23/16 takes precedence)	E21D23/12	E21D23/12		541
E21D23/14	9	Effecting automatic sequential movement of supports, e.g. one behind the other {(advancing of mining machines toward the working face E21C29/02; advancing of conveyors toward the working face E21D23/085)}	E21D23/14	E21D23/14		149
E21D23/142	10	{Measuring the advance of support units with respect to external points of reference}	E21D23/14	E21D23/14		36
E21D23/144	10	{Measuring the advance of support units with respect to internal points of reference, e.g. with respect to neighboring support units or extension of a cylinder}	E21D23/14	E21D23/14		63
E21D23/146	10	{Transmission of signals and commands by cable}	E21D23/14	E21D23/14		52
E21D23/148	10	{Wireless transmission of signals or commands}	E21D23/14	E21D23/14		61
E21D23/16	8	Hydraulic or pneumatic features, e.g. circuits, arrangement or adaptation of valves, setting or retracting devices	E21D23/16	E21D23/16		1287
E21D23/18	9	of advancing mechanisms	E21D23/18	E21D23/18		194
E21D23/20	10	for sequential movement, e.g. one behind the other	E21D23/20	E21D23/20		72
E21D23/22	10	incorporated in mine caps	E21D23/22	E21D23/22		21
E21D23/24	10	the advancing mechanisms being separate from the supporting construction	E21D23/24	E21D23/24		15
E21D23/26	9	Hydraulic or pneumatic control	E21D23/26	E21D23/26		531
