摘要:
The subject invention provides a composition and a process for forming a flexible polyurethane foam sealing device having improved compression set properties at increased temperatures. The sealing device is formed without the use of chemical blowing agents. The composition includes an isocyanate component for reaction with a resin component comprising an isocyanate-reactive component having a functionality of least four and a hydroxyl number of less than 40, a graft dispersion, and a physical blowing agent. The most preferred physical blowing agent is HFC-245 fa or 1,1,1,3,3-pentafluoropropane.
摘要:
The subject invention provides a composition and a process for forming a flexible polyurethane foam sealing device having improved compression set properties at increased temperatures. The sealing device is formed without the use of chemical blowing agents. The composition includes an isocyanate component for reaction with a resin component comprising an isocyanate-reactive component having a functionality of least four and a hydroxyl number of less than 40, a graft dispersion, and a physical blowing agent. The most preferred physical blowing agent is HFC-245 fa or 1,1,1,3,3-pentafluoropropane.
摘要:
Methods and systems relating to a file distribution scheme in a computer network are disclosed that distributes files in an efficient manner that reduces, among other things, network traffic. In an embodiment of the invention, a method for updating a file is disclosed. In such a method, unique chunks in a first version of a digital file are identified. For a second version of the digital file, chunks that are the same as in the first version are identified. Recompilation information is generated and stored for these identified chunks. Also, for the second version of the digital file, chunks in the second version that are different from chunks in the first version are identified. Recompilation information is generated and stored for these identified chunks. With this information, the second version of the digital file is completely defined and can be efficiently stored.
摘要:
The invention disclosed here is a moving headboard for use in connection with a reciprocating floor slat system. It is particularly well-suited for use in connection with load-hauling trailers that have built-in reciprocating floor slat conveyors for unloading the trailer. Trailers of this kind are used in lieu of hydraulic lifts and involve inching the load off the trailer. The moving headboard sweeps the trailer floor clean during the unloading process.
摘要:
Embodiments of the present invention provide compositions and methods for lining a wellbore. In certain aspects, the compositions and methods comprise providing a fluid composition that is solidifiable or gellable on exposure to actinic radiation of a predetermined wavelength at the wall of open-hole wellbore and providing actinic radiation at the predetermined wavelength to solidify or gel the composition. The predetermined wavelength lies in a range from 100 nm to 1500 nm.
摘要:
The invention provides rupturing devices for mitigating the explosive reaction of a casing (121), hollow tubular body or container, particularly a munition, when it is subject to an external thermal hazard threat. The devices are based on the use of shape memory alloys. The device comprises an element of shape memory alloy (123) which is joined together by a connector (122) to form an annulus, which may be located on an exterior surface of a munitions casing (121) or launch such that upon heating through its transition temperature range will cause the annulus to contract radially inwardly, thereby rupturing the munition (121), allowing any build up of pressure to be released quickly. Advantageously, the connector (122) is. reversible such that the device will be capable of being retro-fitted or removed during normal servicing of the munition (121).
摘要:
Embodiments of the present invention provide systems and methods for lining a wellbore. In certain aspects, the systems and methods comprise providing a fluid composition that is solidifiable or gellable on exposure to actinic radiation of a predetermined wavelength at the wall of open-hole wellbore and providing actinic radiation at the predetermined wavelength to solidify or gel the composition. The predetermined wavelength lies in a range from 100 nm to 1500 nm.
摘要:
A method of lining tubing within a wellbore comprises applying a polymerisable fluid composition containing a photoinitiator to the interior surface of that tubing and initiating polymerisation of the composition by exposing it to actinic radiation, suitably light or ultraviolet with wavelength 250 to 800 nm. The composition is preferably stable against heat but polymerises quickly when exposed to the actinic radiation. The composition may be spread onto the tubing and exposed to actinic radiation as soon as it has been spread into a layer, suitably with a tool which skims the tubing surface with applicator pads for dispensing and spreading the composition, immediately followed by exposing the spread composition to actinic radiation. A second option is that the composition is provided as a sleeve which is expanded against the tubing, exposure to actinic radiation preferably then being achieved using light guides or light emitting diodes within the sleeve.
摘要:
A steerable drilling system comprises a rotary drill bit 14 secured to a housing 16, a secondary rotary drill component 22 carried by the housing and rotatable therewith, the second rotary drill component 22 having a gauge dimension greater than that of the rotary drill bit 14, and a drive arrangement operable to displace the secondary rotary drill component 22 relative to the housing 16 while maintaining an axis 24 of the secondary rotary drill component 22 substantially parallel to an axis 18 of the housing 16.
摘要:
The invention relates to a tool for use in wellbore drilling, suitable for use with a drill string for drilling a wellbore having an inner wall, the tool comprising means for generating particles of solid material from the formed inner wall of a drilled wellbore, and means for directing the generated particles to the inner wall of the wellbore and a method of forming a layer of solid particles on the inner wall of a wellbore drilled by such a drill string.