Excavating – Ditch filler
Reexamination Certificate
2000-02-25
2002-07-16
Novosad, Christopher J. (Department: 3671)
Excavating
Ditch filler
C405S179000
Reexamination Certificate
active
06418644
ABSTRACT:
TECHNICAL FIELD
The invention relates to the field of technology and hardware for earthmoving operations predominantly in replacement of the insulation coating of ducts, performed at the design elevations of ducts in the trench, predominantly without interrupting the operation of the insulation coating replacement, and more particularly to the methods and devices for padding the ground below a duct using excavated soil, equipment for soil compacting below a duct and soil compacting mechanisms. Furthermore, the invention can find an application in earth-moving operations in construction of new underground ducts.
BACKGROUND OF THE INVENTION
The advantages of such a technology of replacement of the insulation coating on operating ducts in the trench became obvious long ago to the experts who began making certain efforts for its introduction into practice. Known is the technology of replacement of the insulation coating, in which the duct is held above the trench bottom by stationary supports [S. A. Teylor. “Mechanising the operations on replacement of the insulation coating of operating ducts in the trench” // Neft′, gaz i neftekhimia za rubezohm, 1992, #10, p. 75-83]. In this case padding the ground below a duct is performed by regular earth-moving and construction machinery, due to the use of the above supports. However, the regular construction machinery does not provide a satisfactory solution for the problem of padding the ground below a duct using excavated soil, even when the above supports are applied. It is preferable to replace the insulation coating of the duct during continuous displacement of the entire system of the appropriate equipment without making use of the above supports. This requires more from the technology and equipment for padding the ground below a duct using excavated soil (feeding excavated soil from the dump, its deposition into the trench and compacting below the duct), which requirements cannot be met by the used in practice technology for performing the above-mentioned operations or the construction machinery, or by the other technologies and appropriate hardware which are not used in practice but are known from the state-of-the-art. In this case, the technology of padding the ground below a duct using excavated soil should envisage, and the appropriate device should be capable of, performing its function during its continuous uninterrupted displacement at a velocity which is equal to the velocity of displacement of the entire system (preferably 150 to 100 m/h), and the device should apply a minimal force on the insulation coating, which excludes damage to the coating even at its low strength, as when padding the ground below a duct after a small interval of time (3 to 7 min.) after application of the insulation coating, this time not being enough for some kinds of the coating to acquire its full strength. Furthermore, the device for padding the ground below a duct using excavated soil should have minimal overall dimensions in the direction along the duct for reduction of the length of the unsupported section of the duct to such an extent, as to eliminate or minimize the use of mobile means of supporting a duct. The device should provide a rather high degree of padding the ground below a duct (characterised by a bed coefficient K
y
equal to 0.5 to 1 MN/m
3
) in order to avoid the significant subsequent slumping of the duct and appropriate deformation loads in it. Furthermore, the device for padding the ground below a duct using excavated soil should operate in a reliable manner when displaced over the surface of soil with significant unevenness and a lateral gradient, as well as over soil with low load-carrying capacity, for instance marshland or a layer of loose excavated soil. It is exactly the absence at the present time of such a technology and means for padding the ground below a duct using excavated soil which largely prevents a broad use in practice of the technology of replacement of the insulation coating on the operating ducts in the trench without the use of supports for the duct resting against the trench bottom. Thus, the inventors were faced with a complicated and important problem unsolved in a manner required for practical application, despite the numerous attempts at solving it for many years.
Known is a method of padding the ground below a duct which includes picking-up soil, its deposition into the trench from both sides of the duct and soil compacting in the space below the duct by rammer-type soil compacting organs applying a force on the soil previously deposited in the trench, during continuous displacement over the soil surface along the duct of a vehicle carrying soil feeding and soil compacting organs. Unlike the claimed method, in the known method the travelling unit with a wider base of the vehicle, moves along both edges of the trench, over the soil surface formed during uncovering of the duct, and the soil is picked up from the trench edges (Vasilenko S. K., Bykov A. V., Musiiko V. D. “Technology and system of technical means for overhauling the line oil pipelines without lifting the pipe” // Truboprovodni transport nefti, 1994, #2, p. 25-27]. The vehicle displacement along both edges of the trench complicates the process of placement on and removal from the uncovered duct, possibly causing emergency situations if the vehicle falls off the trench edge and non-uniform slumping of the travelling unit of the vehicle. Furthermore, soil picking-up from the trench edges unreasonably increases the scope of earth-moving operations.
The closest known method to the claimed method is the method of padding the ground below a duct using excavated soil, which include soil picking-up from the dump, soil transportation in the direction from the dump towards the trench with the duct, soil deposition into the trench from both sides of the duct and filling at least part of the trench space with soil, during continuous displacement over the surface of the soil along the duct of a vehicle carrying the soil feeding and transport organs, and compacting the soil at least in the space below a duct by soil compacting organs applying a force on the soil during continuous displacement over the soil surface along the duct, of a vehicle carrying soil compacting organs. Unlike the claimed method, in the known method the vehicle carrying the soil feeding, transport and soil compacting organs, is displaced over the soil surface from the trench side opposite to the dump, whereas the force is applied to the soil by soil compacting organs made in the form of throwers, prior to its deposition into the trench, which accelerate the soil up to the velocity sufficient for dynamic self-compacting of the soil during its deposition into the trench [USSR Author's Certificate 855137, IPC E02F 5/12, 1981]. Displacement of the vehicle over unprepared soil surface results in the vehicle, and the soil compacting organs together with it, rocking when passing over uneven ground, with soil particles (in particular, large-sized rocky inclusions) hitting the surface of the duct insulation coating at a high speed, and breaking it. Furthermore, even with a stable position of the vehicle, it is impossible to direct the high-speed flow of soil below a duct with such a precision as to, on the one hand, eliminate formation of a cavity under the duct, and on the other hand, prevent collision of the high speed soil particles with the insulation coating surface. This method does not permit achievement of the required degree of compacting of soil below a duct, which would provide small enough slumping of the duct, and, therefore, its small deformation loading, this being especially important in performance of this work without interruption of the duct operation. This method is difficult to implement when excavated fertile soil is located on the trench side opposite to that of the mineral soil dump location. For its implementation, this method requires an appropriate device with a long extension of soil feeding organ, this being difficul
Bykov Alexandr V.
Chernaev Valery D.
Koval Andrei B.
Kumylganov Alexandr S.
Leichenko Jury B.
Burns, Doane, Swecker & Mathis, l.L.P.
Obschetvo s Ogranichennoi Otvetstvennostju nauchho-issledovateel
LandOfFree
Apparatus and method for padding the ground below a duct... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for padding the ground below a duct..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for padding the ground below a duct... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2908857