EP0050928B1 - Manufacturing manhole cover frames - Google Patents

Manufacturing manhole cover frames Download PDF

Info

Publication number
EP0050928B1
EP0050928B1 EP81304626A EP81304626A EP0050928B1 EP 0050928 B1 EP0050928 B1 EP 0050928B1 EP 81304626 A EP81304626 A EP 81304626A EP 81304626 A EP81304626 A EP 81304626A EP 0050928 B1 EP0050928 B1 EP 0050928B1
Authority
EP
European Patent Office
Prior art keywords
frame
cover
manhole cover
manhole
jig
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
Application number
EP81304626A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0050928A1 (en
Inventor
David Martin Harvey
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dover Engineering Works Ltd
Original Assignee
Dover Engineering Works Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Dover Engineering Works Ltd filed Critical Dover Engineering Works Ltd
Priority to AT81304626T priority Critical patent/ATE6749T1/de
Publication of EP0050928A1 publication Critical patent/EP0050928A1/en
Application granted granted Critical
Publication of EP0050928B1 publication Critical patent/EP0050928B1/en
Expired legal-status Critical Current

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
    • E02D29/14—Covers for manholes or the like; Frames for covers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/22—Moulds for peculiarly-shaped castings

Definitions

  • This invention relates to the manufacture of manhole cover frames.
  • manhole cover is to be understood as embracing covers for inspection and access openings, ducts, service trenches and the like whether formed as a solid top or as a grating and whether or not sized to permit the passage of a person through the opening spanned by the cover.
  • the most commonly produced type of frame is cast in one piece of cast iron or cast steel and separately from the cast iron or cast steel covers with which it is to be used.
  • Such frames and covers are not generally given machined surfaces, and the manufacturing process is such that the cover does not fit sufficiently closely against the frame with the result that a gas and liquid tight seal is not obtained between them without the introduction of a separate deformable gasket or seal.
  • Frames are also known which are assembled from components made of cast iron or steel and are generally constituted by four perimeter bars, namely (and these are terms of the art) a front end bar, a back end bar, a left hand side bar and a right hand side bar, which are bolted, fixed or welded together at the corners of the frame so as together to form a rigid structural unit. If one wishes to ensure that the joints between the four perimeter bars are gas tight, the faces which .abut when the bars are bolted together are each recessed and the mating such recesses are filled with a molten material, preferably molten lead.
  • a molten material preferably molten lead.
  • Each perimeter bar is of generally L cross-section, and the bars are arranged so that the frame essentially is constituted by a generally L perimeter section which provides a well into which a removable cast iron cover may be sunk to seat on the base of the L cross-section well and seal both on that base and against the upstanding side faces of the well.
  • the faces of each perimeter bar which contact the cover are machined as by milling, and the corresponding faces of the cover are also machined as by grinding.
  • Frames are matched to covers to ensure that the respective machined surfaces fit closely against one another to make the required gas and liquid tight seal and so that the cover and frame make substantially one solid unit with the cover being stable within the frame and not rocking therein when subjected to a moving loading as in the case of fast traffic passing thereover.
  • a method of manufacturing a manhole cover frame comprises forming a mould cavity having a configuration desired of the frame, using a manhole cover to define part of the mould cavity, and introducing a hardenable material when in a flowable condition into the mould cavity so that it will constitute the frame when solidified and have a contour conforming to those regions of the manhole cover which define said part of the mould cavity.
  • the invention further includes an apparatus for use in manufacturing a manhole cover frame comprising means defining a mould cavity and formed in part by a manhole cover such that those regions of the cover which seat in use against the frame constitute mould surfaces of the mould cavity.
  • Practise of the method in accordance with the invention of manufacturing a manhole cover frame reduces the number of operational steps necessary in its production and results in a frame of simpler structure as compared with the aforesaid machined multi-bar construction.
  • the surfaces of a cover which are to seat against a frame in use are machined as by grinding before the cover is used in the moulding process, and when such a cover is paired to the frame moulded against it we have found, surprisingly, under test, that the cover and the frame with the latter moulded of reinforced concrete stand up to a much greater loading before destruction than either of the aforesaid conventionally made manhole cover and frame assemblies.
  • the reason for this is believed to be the much closer fit obtained between the cover and the frame as a result of the moulding technique adopted, and the effect of the increased strength thus obtained should enable a thinner cross-section to be used than hitherto with a consequent saving in cost and reduction in operating weight.
  • the frames as manufactured in accordance with the invention can be produced with relatively unskilled labour as compared with that required to produce the milled, multi-bar construction of frame. Moreover, such frames may be produced in a factory or actually on site using simple «throw-away' moulding jigs.
  • a frame is moulded in one piece of a hardenable or setable material.
  • the setable material is poured into a jig and is actually moulded against those surfaces of a finished cover with which it is to interfit in use. Therefore, the frame is matched automatically to the cover when being made.
  • a jig 1 includes a base 2 which is rectangular in plan and which has upstanding marginal stepped sections 3 around its periphery which provide a ledge 4 and, inwardly thereof, a generally vertical locating surface 5 which is slightly inclined in a direction away from the ledge.
  • the marginal stepped sections 3 as formed above are designed to accept and locate a cast iron cover C which has been machined at its surfaces which will seat against the frame in use.
  • the inverted cover C is of the open top type formed by a honeycomb rib structure r upstanding from a bottom plate p with its perimeter bend defined by side and end flanges f also integral with the bottom plate. Accordingly, it is the external surfaces s and s1 of the flanges f and the marginal region of the bottom plate p, respectively, which are machined.
  • the frame could be moulded to other configurations of cover C with the jig base 2 being suitably configured to locate positively the cover in position.
  • each shutter 7 is provided with an inwardly extending protuberance 9. Additionally, each shutter 7 has its protuberance 9 provided with transverse recesses 10 (see Figure 2).
  • the jig 1 is completed by a top shutter 11 which locates on vertical pins 12 carried by the base 2 to seat on the plate p of the cover C and which is held against the cover by any suitable means such as taper wedges 13 as shown.
  • a packing 14, which may be of neoprene, is provided between the top shutter 11 and the cover plate p to take up any irregularities there might be in the plate surface. The packing 14 would be bonded to the top shutter 11.
  • a continuous cavity 15 defined between the top shutter 11 and the four side shutters 7 down to the ledge 4 of the jig base 2 and adjacent the machined surfaces s and s1 of the flange f and the margin of the plate p of the cover C.
  • a setable material m is introduced into that cavity 15 to fill it, and when that material is sufficiently solidified, the top shutter 11 is removed and the side shutters 7 hinged downwardly, thereby to permit the frame F moulded from the setable material m in the cavity to be removed together with the cover C. Since the frame F has been moulded to the surfaces of the cover C which are to seat against it, a perfect match is made and no further finishing operations are necessary.
  • the moulded one-piece frame F comprises four perimeter bars b each of which has a U-section base s formed by the corresponding protuberance 9 which moulds a recess into the bar and from which is upstanding a marginal flange I.
  • Transverse strengthening ribs (not shown) would be moulded into each frame bar b by the recesses 10 in the shutter protuberances 9.
  • the frame F would, of course, be inverted from the orientation shown, and the base swould be suitably permanently secured around the mouth of a pit opening in a floor or the like.
  • the matching cover C would be laid into the frame F so that its machined surfaces s and s1 seated against the correspondingly moulded surfaces of the frame base s and flange / to make a closely mated interface therewith to prevent the ingress of extraneous matter therebetween.
  • the setable material would conveniently be concrete preferably reinforced as by glass fibre, steel fibre or epoxy resin.
  • reinforcement such as a steel grid could be laid in the cavity to reinforce the concrete in situ.
  • top and hinged shutters and jig base could conveniently be of wood or any other material, for example melamine, suitable for forming a mould wall with respect to concrete.
  • any suitable parting agent may be applied to the moulding surfaces.
  • Frames may be moulded one at a time or in multiples using a number of jigs positioned adjacent one another. It is contemplated that a single jig could be sub-divided to mould a number of frames simultaneously or to mould a multi-span frame seating a plurality of covers, each of which would be used in the moulding process. Whilst the side shutters are shown hinged to the jig base, other means of secural may be equally appropriate. It is to be emphasised that the illustrated frame having a U-section base is but one configuration amongst many which may be moulded using the technique described.
  • That technique enables a frame to be made from but a single operation, namely by moulding, and matched during the moulding process with the cover to be used with the frame. Although such optimum matching is preferred to ensure a closely mated interface, a set of covers may be maintained for moulding purposes, and frames moulded from those covers matched subsequently to other covers.
  • moulding material Whilst reinforced concrete is preferred as the moulding material, other materials which can be cast or moulded such as metal alloys or synthetic plastics may be utilized, and the process and moulding apparatus adapted as may be necessary within the scope of the claims.
  • the moulding process may be performed away from site in a factory or frames could actually be moulded in position on site by means, if wished, of « throw-away simple shutter jigs.
  • the unmachined mating surfaces of the cover are preferably coated with a low friction material such as a polyurethane varnish or a silicone or teflon coating.
  • An alternative moulding jig could comprise a flexible sheet as, for example, of thin PVC or a silicone or polyurethane rubber which is pressed into shape so as to have a base and integral upstanding side walls, the latter being backed externally by a rigid former. After moulding, with the rigid former removed, the sheet would be peeled away from the moulded frame.
  • a flexible sheet mould would not need to be coated with a parting agent and would constitute an inexpensive « throw-away), jig suitable for use on site or in a factory.
  • the base wall of the peelable jig like that of the hinged side jig, would be stood on a suitable moulding table which would be vibrated by conventional means to ensure even filling of the mould cavity. It is envisaged that a top shutter would still be used with the peelable jig.

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)
  • Mechanical Engineering (AREA)
  • Underground Structures, Protecting, Testing And Restoring Foundations (AREA)
  • Special Wing (AREA)
  • Devices For Checking Fares Or Tickets At Control Points (AREA)
  • Packaging For Recording Disks (AREA)
  • Laminated Bodies (AREA)
  • Moulds For Moulding Plastics Or The Like (AREA)
  • Building Environments (AREA)
  • Producing Shaped Articles From Materials (AREA)
  • Mirrors, Picture Frames, Photograph Stands, And Related Fastening Devices (AREA)
  • Wing Frames And Configurations (AREA)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)
EP81304626A 1980-10-27 1981-10-06 Manufacturing manhole cover frames Expired EP0050928B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81304626T ATE6749T1 (de) 1980-10-27 1981-10-06 Herstellung von rahmen fuer mannlochdeckel.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8034487A GB2085796B (en) 1980-10-27 1980-10-27 Manufacturing manhole cover frames
GB8034487 1980-10-27

Publications (2)

Publication Number Publication Date
EP0050928A1 EP0050928A1 (en) 1982-05-05
EP0050928B1 true EP0050928B1 (en) 1984-03-21

Family

ID=10516898

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81304626A Expired EP0050928B1 (en) 1980-10-27 1981-10-06 Manufacturing manhole cover frames

Country Status (19)

Country Link
EP (1) EP0050928B1 (enrdf_load_stackoverflow)
JP (1) JPS57104730A (enrdf_load_stackoverflow)
AT (1) ATE6749T1 (enrdf_load_stackoverflow)
AU (1) AU530825B2 (enrdf_load_stackoverflow)
BE (1) BE890861A (enrdf_load_stackoverflow)
BR (1) BR8106921A (enrdf_load_stackoverflow)
CA (1) CA1169235A (enrdf_load_stackoverflow)
CH (1) CH647029A5 (enrdf_load_stackoverflow)
CY (1) CY1267A (enrdf_load_stackoverflow)
DE (1) DE3162819D1 (enrdf_load_stackoverflow)
DK (1) DK470981A (enrdf_load_stackoverflow)
ES (1) ES506530A0 (enrdf_load_stackoverflow)
FR (1) FR2492867A1 (enrdf_load_stackoverflow)
GB (1) GB2085796B (enrdf_load_stackoverflow)
IT (1) IT1144998B (enrdf_load_stackoverflow)
MY (1) MY8500882A (enrdf_load_stackoverflow)
NO (1) NO813583L (enrdf_load_stackoverflow)
SG (1) SG54684G (enrdf_load_stackoverflow)
ZA (1) ZA816855B (enrdf_load_stackoverflow)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8325048D0 (en) * 1983-09-19 1983-10-19 Dover Eng Works Ltd Covers and frames
FR2630942B1 (fr) * 1988-05-05 1991-04-05 Pont A Mousson Piece de fonderie munie d'une pastille defoncable
BE1008585A3 (nl) * 1994-03-22 1996-06-04 Kruyfhooft Christina Werkwijze voor het vervaardigen van een putdeksel en putdeksel volgens deze werkwijze bekomen.
DE29618587U1 (de) * 1996-10-25 1997-01-02 Hermann-Heinz Burger Gas- und Wasserarmaturen GmbH, 59423 Unna Straßenkappe
GB2335220B (en) * 1998-03-12 2000-06-07 Aco Technologies Plc Access cover and frame
GB2368604B (en) * 2000-11-04 2004-12-01 C I S Ground surface access assemblies
ITPI20110048A1 (it) * 2011-04-26 2012-10-27 Ferb Figli Di Ezio Rossi Spa Procedimento per la fusione contemporanea in un unica forma di piu' getti complementari
US10011971B1 (en) * 2015-07-14 2018-07-03 David L. Neathery Manhole inserts and manhole insert gasket fabrication methods
CN106759505B (zh) * 2016-12-08 2019-04-23 中国一冶集团有限公司 用于市政井盖板的现浇可调节模板及其浇筑方法
CN109865822A (zh) * 2017-12-05 2019-06-11 重庆英格力铸造科技有限公司 一种机械合模铸造机

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE7420923U (de) * 1974-10-31 Guss Und Armaturwerk Kaiserslautern Aus Gußeisen und Beton bestehender Rahmen für Schachtabdeckungen, Straßeneinläufe und dergleichen
FR1013982A (fr) * 1948-07-07 1952-08-06 Neyret Beylier & Piccard Picte Dispositif et procédé de fabrication d'éléments, pour la constitution de dalles pur plafonds ou murs insonorisés
DE1121554B (de) * 1953-06-02 1962-01-04 Dover Eng Works Ltd Rahmen fuer Schacht- oder Mannlochdeckel
US2908063A (en) * 1955-09-16 1959-10-13 Herbert S Jones Mold for forming concrete frames
GB1445565A (en) * 1972-08-02 1976-08-11 Cement & Concrete Ass Concrete articles
NO134760C (enrdf_load_stackoverflow) * 1973-04-13 1976-12-08 Dempa As
GB1468835A (en) * 1974-07-26 1977-03-30 Stoner Saunders Ltd Manhole covers
DE2537257A1 (de) * 1975-08-21 1977-02-24 Passavant Werke Rahmen fuer schachtabdeckungen, strassenablaeufe o.dgl.
GB2066335B (en) * 1979-12-28 1983-06-02 Dover Eng Works Ltd Manhole covers

Also Published As

Publication number Publication date
AU7615281A (en) 1982-05-06
FR2492867A1 (fr) 1982-04-30
EP0050928A1 (en) 1982-05-05
DK470981A (da) 1982-04-28
ATE6749T1 (de) 1984-04-15
GB2085796A (en) 1982-05-06
ES8302154A1 (es) 1983-01-01
NO813583L (no) 1982-04-28
JPS57104730A (en) 1982-06-29
IT8168392A0 (it) 1981-10-27
IT1144998B (it) 1986-10-29
ES506530A0 (es) 1983-01-01
MY8500882A (en) 1985-12-31
CY1267A (en) 1984-11-23
BE890861A (fr) 1982-02-15
ZA816855B (en) 1982-09-29
CA1169235A (en) 1984-06-19
SG54684G (en) 1985-03-08
GB2085796B (en) 1984-06-27
BR8106921A (pt) 1982-07-13
DE3162819D1 (en) 1984-04-26
CH647029A5 (fr) 1984-12-28
AU530825B2 (en) 1983-07-28
FR2492867B1 (enrdf_load_stackoverflow) 1984-05-04

Similar Documents

Publication Publication Date Title
EP0050928B1 (en) Manufacturing manhole cover frames
US20210187793A1 (en) Method Of Forming A Mold Tool For Poured Foam Parts
US6000673A (en) Mold assembly for producing a countertop exhibiting an integrally formed sink bowl and built-up edge and method for producing the same
CN111216218B (zh) 铸造预制混凝土产品的侧成型单元和系统
CN111745794A (zh) 盾构隧道的箱涵模具
US2815548A (en) Method of and means for sealing against blow-by between the separable joint faces of core boxes, pressure molds, and the like
GB2146944A (en) Covers and frames
JPH034494Y2 (enrdf_load_stackoverflow)
US230979A (en) woolnou-gh
CN213038198U (zh) 一种辊模塑钢模板连接装置
JP2001105438A (ja) 樹脂型の製造方法
JP2913541B2 (ja) 雄雌金型原体の同時製造方法
JPH0718173B2 (ja) 土留め用エル形コンクリートブロックの成形装置と成形方法
JPH0776023A (ja) 注型成形用金型及びその製造方法
JPS607045Y2 (ja) 歯科用フラスコ
JPH05344Y2 (enrdf_load_stackoverflow)
JPH0310011Y2 (enrdf_load_stackoverflow)
JPH0732020Y2 (ja) 射出成形金型における入子の取付構造
JPH08142017A (ja) 遠心成形トンネルライナの継手の成形方法
GB2123335A (en) Moulds of rigid plastics foam
CN113752366A (zh) 一种预制楼梯模具及预制楼梯生产方法
US117391A (en) Improvement in methods and apparatus for molding match-plates
GB1600219A (en) Methods of making building modules
JPS6342563B2 (enrdf_load_stackoverflow)
JP2009255259A (ja) バレル研磨機

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): AT DE NL SE

17P Request for examination filed

Effective date: 19820315

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Designated state(s): AT DE NL SE

REF Corresponds to:

Ref document number: 6749

Country of ref document: AT

Date of ref document: 19840415

Kind code of ref document: T

REF Corresponds to:

Ref document number: 3162819

Country of ref document: DE

Date of ref document: 19840426

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 19840911

Year of fee payment: 4

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19841031

Year of fee payment: 4

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19841106

Year of fee payment: 4

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19841231

Year of fee payment: 4

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

26N No opposition filed
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AT

Effective date: 19851006

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19851007

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19860501

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19900703

EUG Se: european patent has lapsed

Ref document number: 81304626.5

Effective date: 19860730