US1908909A - Manhole protector - Google Patents
Manhole protector Download PDFInfo
- Publication number
- US1908909A US1908909A US611202A US61120232A US1908909A US 1908909 A US1908909 A US 1908909A US 611202 A US611202 A US 611202A US 61120232 A US61120232 A US 61120232A US 1908909 A US1908909 A US 1908909A
- Authority
- US
- United States
- Prior art keywords
- frame
- manhole
- ring
- gasket
- band
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D29/00—Independent underground or underwater structures; Retaining walls
- E02D29/12—Manhole shafts; Other inspection or access chambers; Accessories therefor
Definitions
- the invention relates to manholes, and particularly to protective means for uncovered manholes.
- Manholes such as those in streets and roadways, normally include cast metal frames disposed at the street level, and provided with inner annular recesses for receiving removable covers.”
- the framesand manhole covers are made flush with the ground level.
- surface water on the street can drain into the manhole upon the workman. This. condition is particularly annoying in wet weather, although when the manholejis disposed adjacentacurb, it may exist for a longtime after rain or snow has ceased falling.
- the cover of a manhole in a street or roadway is removed, it isnecessary to erect a railing, or like obstruction, to prevent vehicles and per sons from moving over the opening,
- tective device adapted to be fitted with the manhole frame when the cover is removed, to prevent water from draininginto the manhole, and, at the same time, to present an obstruction to warn traffic of the uncovered manholeyand prevent it from passing thereover.
- Fig. 1 is a perspective View disclosing the protective device installed in an uncovered .n anhole;
- Fig. 2 is avertical sectional View, likewise disclosing the deviceinstalled
- Fig. 3 is an enlarged fragmentary vertical section through the protective .device'per se;
- Fig; 4 is a fragmentary plan View of the protective device;
- Figs. land 2 the manhole
- the present invention comprehends a pro- 1932. Serial 1 ⁇ To. 611,202.
- the frame which may be disposed adjacent a curb 10, is delineated by a frame casting 11, having its upper surface 12, flush with the level of the street or roadway 13.
- the frame is illustrated as supported by beams 1 1 and having depending lugs 15 engaged betweenthe beams?
- the upper inner periphery of the frame is recessed at 16 to provide a seat fora manhole cover (not illustrated) which normally closes the opening in the frame.
- the wall 20 of the recess is usually inclined fromthe vertical to faeilitate'insertion and removal of the cover.
- the present invention comprehends a ring which may be insertedin the recess 16 at times when the cover is removed, and may be removed when it is again desired to re-- place the cover.
- the ring includes a strip of metal 17 bent to conform generally to the contour of the recess 16 and having its ends 18 and 19 provided with interfitting tongues and grooves 21 and 22.
- a band 24 of angle iron.
- flanges 25, 26 apertured to receive an adjusting member 27
- the adjusting member may comprise a shank havingnuts 28 threaded thereto. By turning the latter,'the flanges 25, 26 may be moved'apart to expand the members 23 and 24.
- Extending about the member 17 is a continuous band 31 of rubber or similar flexible gasket material.
- the lower edge of the band is preferably tapered, as indicated at 32, to compensate for the inclination of wall 20 of the manhole frame, and terminates in an in-' wardly directed flange 33 which underlies thelower leg 34 ofthe angle iron 24.
- the protective ring, byflreason ofthe initial formation of members 17, 24 and 31 is normally of less diameter than the recess 16 so that'it may be readily inserted therein.
- Fig. 5 is a fragmentary vertical section the ring to compress the gasketring 31 and thus form a watertight seal with the manhole frame.
- the'gasket is supported and may be compressed about its en-.
- the protective ring may be of any suitable height, but preferably such that when in place it will extend above the street level a distance substantially equal to or greater than the height of the curb 10.
- clamping devices 35 may be applied to compress the bottom flange 84c of the gasket. These devices may portions 36, adapted to engage in slots 37 formed in the leg 33 of the angle member 24;, and lower hook portions 38 adapted to.
- the clamping devices may be positioned, and
- the; protectivering may be removedby releasinggtheexpandingmeans 27 28, al lowing the ring to. contract to its: normalsize, and by neleasing and. removing from;
- theringmay bra-nom na y. expanded so. as to: be; on greater diameter than the frame recess and:
- ililfisfQlzlIl'z of the invention is. depicted in- Fig,- GsWlmIZein,- fianges 26; are aperturedttoreceive contracting IIlQZEIISQOHSlSt-lfigfOfi a bolt 45.; and;
- The-latter may beadfiustedtQcmn ra t he protectlve: ring to permit: it. t -be;f inserted into-the manhole frame; After being inserted into the frame-j and the contracting means released the ring: will, eX-j nandr y. i s; o resiliency tmfirmly engage the. frame and. present, a water-tight. wall;
- a removable member extending upwardly from said frame and defining an unbroken wall aro nd. the manhole to; prevententrance of surface fluids, and means. for releasably securing said wall member with respect to said frame.
- a removable member extending upwardly from said frame and defining an unbroken wall aro nd. the manhole to; prevententrance of surface fluids, and means. for releasably securing said wall member with respect to said frame.
- a protective ring adapted. to seat. uppn said; frame, aboutthe; openlng therein, said ring.
- a; protective ring adapted. to. seat. upon. said frame 'aboutthe open ng therein, said. r ng having a gasket portion at the lower. surface.
- a protectivering fOI-d SPOSitiOmupOH a manhole frame to provide a-wallaboutgthe opening in such frame,.said:ring havin a ring-like. gasket. portion-Jet, the, lower. sur ace thereon for contact.
- a protective ring for disposition upon a manhole frame to provide a wall about the opening in such frame; said ring comprising a member of angle cross-section having an inwardly directed lower flange and an upwardly directed flange, means adjacent the ends of the members for varying the diameter of the ring, a band of greater height than said upwardly directed flange secured thereaboiut and having interfitted tongued and grooved ends; adjustable means engaged with said inwardly directed flange and engageable with the manhole frame for drawing the ring toward the frame; a continuous flexible gasket extending about said band and having an annular portion underlying said inwardly directed flange, and an inverted U- shaped member engaged over said band above the tongued and grooved ends thereof.
- a protective ring for insertion in the opening of a manhole frame comprising a band having the end portions thereof provided with interfitting tongues and grooves, a flexible gasket extending con-' tinuously about said band, and means for varying the diameter of said band.
- a protective ring for insertion in the opening of amanhole frame comprising a band having the end portions thereof provided with interfitting tongues and grooves, and a flexible gasket extending continuously about said band.
- a protective ring for insertion in the opening of a manhole frame for preventing the entrance of surface fluids into the manhole, said ring comprising a continuous flexible gasket, and means within said gasket for expanding it against the walls of the manhole opening, said gasket when in place extending above the upper surface of said frame.
Landscapes
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Underground Structures, Protecting, Testing And Restoring Foundations (AREA)
Description
y 6, 1933. c. w. MANZ 1,908,909
MANHOLE PROTECTOR Filed May 13, 1932 7% 6 GhristianWiHmm Manz 24 33 36 37 BY 34 M ATTORNEY Patented May 16, 1933 UNITED STATES CHRISTIAN WILLIAM MANZ, 01E BUFFALO, NEW YORK MANHOLE PROTECTOR i Application filed May 13,
The invention relates to manholes, and particularly to protective means for uncovered manholes.
Manholes such as those in streets and roadways, normally include cast metal frames disposed at the street level, and provided with inner annular recesses for receiving removable covers." In order to obviate an obstruction inthe street or roadway, the framesand manhole covers are made flush with the ground level. When the cover is removed and a workman has entered the manhole, surface water on the street can drain into the manhole upon the workman. This. condition is particularly annoying in wet weather, although when the manholejis disposed adjacentacurb, it may exist for a longtime after rain or snow has ceased falling. Further, whenthe cover of a manhole in a street or roadway is removed, it isnecessary to erect a railing, or like obstruction, to prevent vehicles and per sons from moving over the opening,
tective device adapted to be fitted with the manhole frame when the cover is removed, to prevent water from draininginto the manhole, and, at the same time, to present an obstruction to warn traffic of the uncovered manholeyand prevent it from passing thereover. 7
These and other objects and advantages will become apparent from the following description of the typical embodiments ofthe invention illustrated .in the accompanying drawing, wherein:
Fig. 1 is a perspective View disclosing the protective device installed in an uncovered .n anhole;
Fig. 2 is avertical sectional View, likewise disclosing the deviceinstalled Fig. 3 is an enlarged fragmentary vertical section through the protective .device'per se; Fig; 4 is a fragmentary plan View of the protective device;
taken along line 55 of Fig. lg-and Fig. 6 is a fragmentary plan'view of a modified construction. i f As shown in Figs. land 2, the manhole,
The present invention comprehends a pro- 1932. Serial 1\To. 611,202.
which may be disposed adjacent a curb 10,, is delineated by a frame casting 11, having its upper surface 12, flush with the level of the street or roadway 13. Accordingto con-* ventional practice, the frame is illustrated as supported by beams 1 1 and having depending lugs 15 engaged betweenthe beams? The upper inner periphery of the frame is recessed at 16 to provide a seat fora manhole cover (not illustrated) which normally closes the opening in the frame. The wall 20 of the recess is usually inclined fromthe vertical to faeilitate'insertion and removal of the cover. I i
The present invention comprehends a ring which may be insertedin the recess 16 at times when the cover is removed, and may be removed when it is again desired to re-- place the cover. As illustrated the ring includes a strip of metal 17 bent to conform generally to the contour of the recess 16 and having its ends 18 and 19 provided with interfitting tongues and grooves 21 and 22. Secured by fasteners 23 to the lower inner wall of member 17 is a band 24: of angle iron. At the ends of the latter are flanges 25, 26 apertured to receive an adjusting member 27 The adjusting member may comprise a shank havingnuts 28 threaded thereto. By turning the latter,'the flanges 25, 26 may be moved'apart to expand the members 23 and 24. Extending about the member 17 is a continuous band 31 of rubber or similar flexible gasket material. The lower edge of the band is preferably tapered, as indicated at 32, to compensate for the inclination of wall 20 of the manhole frame, and terminates in an in-' wardly directed flange 33 which underlies thelower leg 34 ofthe angle iron 24. f The protective ring, byflreason ofthe initial formation of members 17, 24 and 31 is normally of less diameter than the recess 16 so that'it may be readily inserted therein.
' The means 27 ,28 may be adjusted to expand Fig. 5 is a fragmentary vertical section the ring to compress the gasketring 31 and thus form a watertight seal with the manhole frame. By reason of the interlocking tongues and grooves 21,22, the'gasket is supported and may be compressed about its en-.
tire periphery. The protective ring may be of any suitable height, but preferably such that when in place it will extend above the street level a distance substantially equal to or greater than the height of the curb 10.
As another or additional precaution againsttheleakageof water between the ring and the manhole frame, clamping" devices 35 may be applied to compress the bottom flange 84c of the gasket. These devices may portions 36, adapted to engage in slots 37 formed in the leg 33 of the angle member 24;, and lower hook portions 38 adapted to.
engage under the lower edge of'the manhole frame 11.. After the protective ring-has been placed in the manhole} frame; the clamping devices may be positioned, and
tightened to draw the ring; closely against the horizontal seat surface of; the frame-.
7 NVhen it is desired tovreplace the-manhole cover, the; protectivering may be removedby releasinggtheexpandingmeans 27 28, al lowing the ring to. contract to its: normalsize, and by neleasing and. removing from;
engaged position. theturnbnekles or, clampingmeans 35 36 38; v h
In O d tQ sa eguard the. workman. fr m; being pinched by closing or contracting 2 movement on thetongue-andr groove-endsof the band; 1-71 or by contact with the;- sharp, edge.- presented' by: these ends an inverted UI-shapedguarcbmemberv 39.- may be; fitted; thereouen; and may be, held in position: by
l? fastenens 41., The guard, member pref-er ably issecuned to but one end ofi'thebandi LZ'and .has.=a,s1ir1ing it with, the oth end;
so that it wilLnot interfere, with; contraction on expansion of; the protective; ring.
The device illustrated in 1 2 !and 4:
is normally contnacted to be. of: smaller diamete than the re ess 16 insthe manh e:
ram and; m y h ernan edby the means 2,7, .28 to; tightly engagfi: the;.verti cal Walls;
of; the recess. However-,if desired: theringmay bra-nom na y. expanded so.= as to: be; on greater diameter than the frame recess and:
. maybe contracted, to reduce its 'diameterto p rmi s r ion i t the-recess. ililfisfQlzlIl'z of the invention is. depicted in- Fig,- GsWlmIZein,- fianges 26; are aperturedttoreceive contracting IIlQZEIISQOHSlSt-lfigfOfi a bolt 45.; and;
a.nut 2 6., I The-latter may beadfiustedtQcmn ra t he protectlve: ring to permit: it. t -be;f inserted into-the manhole frame; After being inserted into the frame-j and the contracting means released the ring: will, eX-j nandr y. i s; o resiliency tmfirmly engage the. frame and. present, a water-tight. wall;
63? about the manhole,
' It will: be-understood that the devicesdescribed. and illustrated herein are merely illustrative; of; the inventiveprinciples in valved; angl that. theseprinciples\ may. be
emb d d-. 11 etieeshavingwther stn oturaly characteristics and arrangements, all within the purview of this invention.
What is claimed is:
1. In combination with a manhole frame, a removable member extending upwardly from said frame and defining an unbroken wall aro nd. the manhole to; prevententrance of surface fluids, and means. for releasably securing said wall member with respect to said frame. comprise turnbucltl'es halVlT-lg upper headed opening and, extending upwardly beyond. the
upper. edge of. said frame, said. member CQTl}-- stitutlng a. continuous. and: unbroken wall about the opening for preventing surface fluids from entering thec manhol'e through. the opening inthe; frame.
a 4. In, combination, with. amanhol'eframe,
having an. opening with substantially up,-
right. walls; an. expansibl'e.v member inserted Within. said; opening and. extending upwardly,
beyond the, upper sunface. of the frame said.
member being oontinuous, andpresenting anv unbroken wall about theopem'ng,
. 5.. Amanhole protective device'comprising a ring adapted to. seat upon. amanhole. frame.
andtoextendf upwardly. above thefupper sur:
face, thereof; said. ring including gasket.
means and-means for. pressing tlie gasket. meansintol. watertightgcontact. with. the manhole fiiame, $3111 ring and gasket means, con:
stitnting. d'aun to prevent surface fluids.
rom entering. the manhole, a
. 6;, combination. with! a manhole, frame,.,
a protective ring; adapted. to seat. uppn said; frame, aboutthe; openlng therein, said ring.
having a gasket portion at the lower. surface.
thereofwfor contact Withthe frame .and said ring and; gasket, portion. constitutingv a. dam
to. preven surface. fluids. from; entering the manhole.
7 In combination with a.manliole.frame,.
a; protective ring, adapted. to. seat. upon. said frame 'aboutthe open ng therein, said. r ng having a gasket portion at the lower. surface.
thereof. for contact I with. the. frame-an means for dnawing said; ring, downwardly. for. oompr sslng said; gasketportlon against the; frame. a
.8; A protectivering fOI-d SPOSitiOmupOH a manhole frame to provide a-wallaboutgthe opening insuch frame,.said:ring havin a ring-like. gasket. portion-Jet, the, lower. sur ace thereon for contact. Witht the frame and means engaged with the-ringandwengageablei with: the. frame for: drawing said; ring. to-
ward the frame to thereby compress said gasket portion.
9. A protective ring for disposition upon a manhole frame to provide a wall about the opening in such frame; said ring comprising a member of angle cross-section having an inwardly directed lower flange and an upwardly directed flange, means adjacent the ends of the members for varying the diameter of the ring, a band of greater height than said upwardly directed flange secured thereaboiut and having interfitted tongued and grooved ends; adjustable means engaged with said inwardly directed flange and engageable with the manhole frame for drawing the ring toward the frame; a continuous flexible gasket extending about said band and having an annular portion underlying said inwardly directed flange, and an inverted U- shaped member engaged over said band above the tongued and grooved ends thereof.
10. A protective ring for insertion in the opening of a manhole frame, said ring comprising a band having the end portions thereof provided with interfitting tongues and grooves, a flexible gasket extending con-' tinuously about said band, and means for varying the diameter of said band.
11. A protective ring for insertion in the opening of amanhole frame; said ring comprising a band having the end portions thereof provided with interfitting tongues and grooves, and a flexible gasket extending continuously about said band.
12. A protective ring for insertion in the opening of a manhole frame for preventing the entrance of surface fluids into the manhole, said ring comprising a continuous flexible gasket, and means within said gasket for expanding it against the walls of the manhole opening, said gasket when in place extending above the upper surface of said frame.
CHRISTIAN WILLIAM MANZ.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US611202A US1908909A (en) | 1932-05-13 | 1932-05-13 | Manhole protector |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US611202A US1908909A (en) | 1932-05-13 | 1932-05-13 | Manhole protector |
Publications (1)
Publication Number | Publication Date |
---|---|
US1908909A true US1908909A (en) | 1933-05-16 |
Family
ID=24448035
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US611202A Expired - Lifetime US1908909A (en) | 1932-05-13 | 1932-05-13 | Manhole protector |
Country Status (1)
Country | Link |
---|---|
US (1) | US1908909A (en) |
Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3142234A (en) * | 1959-12-21 | 1964-07-28 | Fred V Maloon | Manhole shield |
US4302126A (en) * | 1979-12-27 | 1981-11-24 | Fier Raymond L | Manhole cover support ring |
US4466219A (en) * | 1982-01-04 | 1984-08-21 | Campolito James J | Adjustable manhole cover |
US4867600A (en) * | 1987-07-23 | 1989-09-19 | Bowman Harold M | Polygonal manhole cover support |
US4867601A (en) * | 1987-07-23 | 1989-09-19 | Bowman Harold M | Sturdy adjustable manhole cover support |
US4872780A (en) * | 1987-07-23 | 1989-10-10 | Bowman Harold M | Manhole cover support with box flanging |
US4927290A (en) * | 1987-07-23 | 1990-05-22 | Bowman Harold M | Manhole cover support resistant to water infiltration |
US4963053A (en) * | 1987-07-23 | 1990-10-16 | Bowman Harold M | Multicomponent wales and bases for manhole cover supports |
US4966489A (en) * | 1987-07-23 | 1990-10-30 | Bowman Harold M | Manhole cover support having interbraced top members |
US4969771A (en) * | 1987-07-23 | 1990-11-13 | Bowman Harold M | Manhole cover support having enhanced grip |
US5021261A (en) * | 1987-07-23 | 1991-06-04 | Bowman Harold M | Process for making a manhole cover support having enhanced grip |
US5150984A (en) * | 1987-07-23 | 1992-09-29 | Harold M. Bowman | Stiffening flanges for deformation resistance of manhole cover support |
US5184912A (en) * | 1989-06-06 | 1993-02-09 | Harold M. Bowman | Split-ring manhole cover support |
USRE34550E (en) * | 1987-07-23 | 1994-02-22 | Bowman; Harold M. | Sturdy adjustable manhole cover support |
US5316407A (en) * | 1992-07-15 | 1994-05-31 | Miller Wayborn M | Manhole cover support |
US6007270A (en) * | 1993-07-02 | 1999-12-28 | Bowman; Harold M. | Manhole frame assembly |
US6955498B1 (en) * | 2003-08-20 | 2005-10-18 | Mccuan Scott | Circular conduit opening closure device |
US20140041311A1 (en) * | 2004-11-04 | 2014-02-13 | Paul Richard Auckland | Temporary cover assembly for a void |
US10214345B1 (en) * | 2011-12-12 | 2019-02-26 | Cameron Gordon Howie | Entryway protective collar |
-
1932
- 1932-05-13 US US611202A patent/US1908909A/en not_active Expired - Lifetime
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3142234A (en) * | 1959-12-21 | 1964-07-28 | Fred V Maloon | Manhole shield |
US4302126A (en) * | 1979-12-27 | 1981-11-24 | Fier Raymond L | Manhole cover support ring |
US4466219A (en) * | 1982-01-04 | 1984-08-21 | Campolito James J | Adjustable manhole cover |
US5021261A (en) * | 1987-07-23 | 1991-06-04 | Bowman Harold M | Process for making a manhole cover support having enhanced grip |
USRE34550E (en) * | 1987-07-23 | 1994-02-22 | Bowman; Harold M. | Sturdy adjustable manhole cover support |
US4872780A (en) * | 1987-07-23 | 1989-10-10 | Bowman Harold M | Manhole cover support with box flanging |
US4927290A (en) * | 1987-07-23 | 1990-05-22 | Bowman Harold M | Manhole cover support resistant to water infiltration |
US4963053A (en) * | 1987-07-23 | 1990-10-16 | Bowman Harold M | Multicomponent wales and bases for manhole cover supports |
US4966489A (en) * | 1987-07-23 | 1990-10-30 | Bowman Harold M | Manhole cover support having interbraced top members |
US4969771A (en) * | 1987-07-23 | 1990-11-13 | Bowman Harold M | Manhole cover support having enhanced grip |
US4867600A (en) * | 1987-07-23 | 1989-09-19 | Bowman Harold M | Polygonal manhole cover support |
US5150984A (en) * | 1987-07-23 | 1992-09-29 | Harold M. Bowman | Stiffening flanges for deformation resistance of manhole cover support |
US4867601A (en) * | 1987-07-23 | 1989-09-19 | Bowman Harold M | Sturdy adjustable manhole cover support |
US5184912A (en) * | 1989-06-06 | 1993-02-09 | Harold M. Bowman | Split-ring manhole cover support |
WO1993018240A1 (en) * | 1992-03-04 | 1993-09-16 | Bowman Harold M | Stiffening flanges and gussets for deformation resistance of manhole cover support |
US5316407A (en) * | 1992-07-15 | 1994-05-31 | Miller Wayborn M | Manhole cover support |
US6007270A (en) * | 1993-07-02 | 1999-12-28 | Bowman; Harold M. | Manhole frame assembly |
US6955498B1 (en) * | 2003-08-20 | 2005-10-18 | Mccuan Scott | Circular conduit opening closure device |
US20140041311A1 (en) * | 2004-11-04 | 2014-02-13 | Paul Richard Auckland | Temporary cover assembly for a void |
US10214345B1 (en) * | 2011-12-12 | 2019-02-26 | Cameron Gordon Howie | Entryway protective collar |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US1908909A (en) | Manhole protector | |
US5628152A (en) | Adjustable manhole cover support with shield | |
US3712009A (en) | Manhole closure assembly with valve relief means | |
US5899024A (en) | Manhole adjustment ring | |
US7753617B1 (en) | Utility cover system | |
US5536110A (en) | Transition collar and spacing device for use in road construction | |
CA1287247C (en) | Adjustable manhole top | |
US4591290A (en) | Combination adjustable valve box adapter and replacement for broken valve boxes | |
US6752565B2 (en) | Manhole cover system | |
FI74318B (en) | ANORDNING VID DAGVATTEN- OCH NEDSTIGNINGSBRUNNAR FOER ATT BEGRAENSA LOKALA VARIATIONER I MARKNIVAON. | |
US5318376A (en) | Manhole frame | |
US3263580A (en) | Safety adaptor for manholes | |
US5184912A (en) | Split-ring manhole cover support | |
US4608787A (en) | Manhole seal construction | |
KR100241323B1 (en) | Cover assembly , cover and receiver for underground structure | |
US4963053A (en) | Multicomponent wales and bases for manhole cover supports | |
KR101191138B1 (en) | Anti-slip manhole cover | |
US9695569B1 (en) | Manhole cover sealing device | |
WO1993018240A1 (en) | Stiffening flanges and gussets for deformation resistance of manhole cover support | |
AU2018100184A4 (en) | Coverplate assembly | |
JP2960706B2 (en) | Lid body of underground structure lid | |
JPS628567B2 (en) | ||
CN218204569U (en) | Inspection shaft structure that noise control sound anti-settling | |
HU222068B1 (en) | Manhole cover | |
KR101350472B1 (en) | Manhole cover have a locking apparatus and manhole frame |