1. A medical assembly comprising:
a stent;
a catheter assembly comprising a catheter body and a balloon having the stent positioned on the balloon, the balloon having a deflated configuration and capable of being enlarged to an expanded configuration; and
a releasable connection between the stent and the catheter body, wherein the releasable connection retains the stent on the catheter assembly when the balloon is in the deflated configuration, wherein the releasable connection is formed in a region of the catheter body axially distal or proximal to the balloon, and the releasable connection releases the stent from the catheter body in response to enlargement of the balloon or when the balloon has been enlarged to an expanded configuration, wherein the releasable connection is located between an inner surface of the stent and an outer surface of the catheter body.
2. The assembly of claim 1, wherein the stent is a biodegradable stent.
3. The assembly of claim 1, wherein the releasable connection releases off of the stent.
4. The assembly of claim 1, wherein the releasable connection releases off of the catheter.
5. The assembly of claim 1, further comprising an intermediary material between the releasable connection and the stent, the releasable connection and the catheter body, or the combination thereof.
6. The assembly of claim 5, wherein the intermediary material is a coating.
7. The assembly of claim 5, wherein the releasable connection releases off of the intermediary material.
8. A method for constructing a medical assembly comprising:
placing a stent over a balloon of a catheter assembly;
forming a releasable connection between the stent and the catheter assembly such that in response to the enlargement of the balloon or when the balloon has been enlarged to an expanded configuration, the stent is detached from the catheter assembly,
wherein the forming a releasable connection comprises:
depositing an adhesive material on an outer surface of the catheter assembly to form the releasable connection, the adhesive material being of the type that allows for the detachment of the stent from the catheter assembly in response to the enlargement of the balloon or when the balloon has been enlarged to an expanded configuration; and
applying pressure to the stent to allow the adhesive material to contact the stent and catheter assembly to form the releasable connection;
applying heat to assist the pressure to form the releasable connection formed by the adhesive material.
9. The method of claim 8, wherein the balloon is in a collapsed configuration when the releasable connection is formed between the stent and the catheter assembly.
10. The method of claim 8, wherein the stent is a biodegradable stent.
11. The method of claim 8, wherein the releasable connection disengages from the stent.
12. The method of claim 8, wherein the releasable connection disengages from the balloon.
13. The method of claim 8, wherein the releasable connection is configured to break in parts to disengage the stent from the balloon.
14. The method of claim 8, wherein the adhesive material secures the inner surface of the stent to the outer surface of the catheter.
15. The method of claim 8, wherein the stent is a biodegradable stent and the method of forming the releasable connection comprises
applying a solvent to an inner surface of the biodegradable stent andor an outer surface of the balloon; followed by
crimping the biodegradable stent to the balloon; followed by
removing the solvent.
16. The method of claim 8, wherein the stent is a biodegradable stent and the method of forming the releasable connection comprises
applying a solvent to an inner surface of the biodegradable stent andor an outer surface of the catheter assembly; prior to
placing the biodegradable stent over the balloon wherein the diameter of the stent allows for a fitted mate between the catheter assembly and the stent such that adjusting the diameter of the stent once positioned over the balloon is not required; followed by
removing the solvent.
17. The method of claim 8, wherein the stent includes a material on an inner surface thereof andor the catheter assembly includes a material on the outer surface thereof, and the method of forming the releasable connection comprises
applying a solvent to the material on the stent andor the material on the catheter assembly; followed by
crimping the stent on the catheter assembly; followed by
removing the solvent.
18. The method of claim 17, wherein the releasable connection disengages from the material on the stent, the material on the balloon, the material on the catheter assembly in a region outside of the balloon, or a combination thereof.
19. The method of claim 8, wherein the stent includes a material on an inner surface thereof andor the catheter assembly includes a material on the outer surface thereof, and the method of forming the releasable connection comprises
applying a solvent to the material on the stent andor the material on the catheter assembly; prior to
placing the stent over the balloon wherein the diameter of the stent allows for a fitted mate between the catheter assembly and the stent such that adjusting the diameter of the stent once positioned over the balloon is not required; followed by
removing the solvent.
20. The method of claim 19, wherein the releasable connection disengages from the material on the stent, the material on the balloon, the material on the catheter assembly in a region outside of the balloon, or a combination thereof.
21. The method of claim 8, wherein the forming the releasable connection comprises:
injecting a melted material between the catheter assembly and the stent;
applying a melted material between the catheter assembly and the stent followed by crimping the stent on the catheter assembly;
applying a melted material on an inner surface of the stent andor on an outer surface of the catheter assembly prior to placing the stent over the balloon; or
applying a melted material on an inner surface of the stent andor on an outer surface of the catheter assembly prior to crimping the stent on the catheter assembly.
22. The method of claim 8, wherein the forming the releasable connection comprises:
applying ultrasonic energy to the stent andor the catheter assembly to connect the stent to the catheter assembly;
applying vibration to the stent andor the catheter assembly to connect the stent to the catheter assembly;
spinning the stent around the balloon, spinning the balloon within the stent, or spinning both the balloon and the stent to connect the stent to the catheter assembly; or
applying an electromagnetic energy to the stent andor the catheter assembly to connect the stent to the catheter assembly.
23. The method of claim 22, wherein the stent is a biodegradable stent.
24. The method of claim 22, wherein the stent includes a material deposited on an inner surface of the stent andor the catheter assembly includes a material deposited on the outer surface of the catheter assembly for allowing the stent to be connected to the catheter assembly or for enhancing or facilitating the connection of the stent to the balloon.
25. The method of claim 22, wherein the electromagnetic energy is radio frequency energy, microwave energy, or infrared energy.
26. The method of claim 8, wherein the stent is a biodegradable stent and the method of connecting the stent to the catheter assembly includes laser welding the stent to the catheter assembly.
27. The method of claim 8, wherein forming the releasable connection comprises laser welding a material between the stent and the catheter assembly so as to cause the connection of the stent to the catheter assembly.
28. A method for constructing a medical assembly comprising:
placing a stent over a balloon of a catheter assembly; and
forming a releasable connection between the stent and the catheter assembly by applying heat using a heat source positioned between a surface of the stent and a surface of the catheter assembly such that in response to the enlargement of the balloon or when the balloon has been enlarged to an expanded configuration, the stent is detached from the catheter assembly,
wherein the stent is a biodegradable stent and the method of forming the releasable connection comprises
applying the heat to weld an inner surface of the biodegradable stent to an outer surface of the catheter assembly to form the connection between the stent and the catheter assembly.
29. The method of claim 28 additionally including applying inward radial pressure to the stent that reduces the diameter of the stent during the application of the heat andor subsequent to the application of heat.
30. The method of claim 28, wherein the method of forming a releasable connection additionally comprises crimping the stent on the catheter assembly and wherein heat is applied
prior to crimping of the stent on the catheter assembly;
during the crimping of the stent on the catheter assembly; andor
subsequent to crimping of the stent on the catheter assembly.
31. The method of claim 28, wherein the heat is applied by a heating tool, or by an electric current.
32. A method for constructing a medical assembly comprising:
placing a stent over a balloon of a catheter assembly; and
forming a releasable connection between the stent and the catheter assembly such that in response to the enlargement of the balloon or when the balloon has been enlarged to an expanded configuration, the stent is detached from the catheter assembly,
wherein the forming the releasable connection comprises:
placing a heating element between the stent and the catheter assembly; and
applying heat to weld the stent to the catheter assembly.
33. The method of claim 32, wherein the stent is a biodegradable stent made completely or in-part from a polymeric material.
34. The method of claim 32, wherein the stent includes a material deposited on an inner surface thereof andor the catheter assembly includes a material deposited on an outer surface thereof, such that application of heat to the material on the stent andor the material on the catheter assembly allows for connection of the stent to the catheter assembly.
35. The method of claim 34, wherein the material on the stent andor the catheter assembly has a lower melting temperature than the stent and the catheter assembly.
36. The method of claim 34, wherein the material on the stent andor the catheter assembly has a higher melting temperature than the stent and the assembly.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A process for pyrolyzing a wide boiling range vaporizable hydrocarbon feedstock or mixtures of hydrocarbon feedstocks having a wide boiling range, comprising a variety of hydrocarbons of differing carbonhydrogen ratios andor molecular weights in a pyrolysis furnace having a convection section, least two sets of radiant pyrolysis coils, and a vapor distribution header to produce olefins and other pyrolysis products, comprising:
a. heating and partially vaporizing a feedstock, and feeding the partially vaporized feedstock to a vaporliquid separator device to produce fractions comprising separate vapor and liquid phases;
b. feeding the vapor phase fraction to the vapor distribution header and then to a first set of radiant pyrolysis coils of a pyrolysis furnace operated at a first set of cracking conditions where the hydrocarbons are cracked to produce olefins; and
c. heating and fully vaporizing the liquid phase fraction from the vaporliquid separator, and feeding the vapor phase thus created to the vapor distribution header and then to a second set of radiant coils of the pyrolysis furnace operated at a second set of cracking conditions where the hydrocarbons are cracked to produce olefins.
2. The process of claim 1 wherein said cracking conditions in the particular set of radiant pyrolysis coils includes feed rate, residence time, temperature history, heat input and dilution steam to feed ratio.
3. The process of claim 1 wherein the hydrocarbon feedstock is selected from the group of fully vaporizable feedstocks consisting of (i) natural gas liquids (NGLs), (ii) condensate, (iii) mixtures of gas oil, naphtha andor gasoline, (iv) synthetic hydrocarbons, and (v) mixtures of vacuum gas oil with naphtha added to prevent solidification of paraffin wax contained in the feedstock in un-heated storage and transportation facilities.
4. The process of claim 3 wherein the hydrocarbon feedstock is a condensate comprising a wide-boiling point range feed, with a density from 0.71 to 0.80 gcm3, a hydrogen content from 13.0% to 15%, an initial boiling point from ambient temperature to a final boiling point of about 1000\xb0 F. (538\xb0 C.
5. The process of claim 3 wherein the hydrocarbon feedstock comprises mixtures of vacuum gas oil with naphtha added to prevent solidification of paraffin wax contained in the feedstock in un-heated storage and transportation facilities.
6. The process of claim 1 wherein a mixture of hydrocarbon feedstocks are used.
7. The process of claim 1 wherein a diluent gas or liquid or mixtures thereof are added to the hydrocarbon feedstock prior to entering the radiant pyrolysis coils.
8. The process of claim 7 wherein said diluent gas is selected from the group consisting of steam, methane, ethane, nitrogen, hydrogen, natural gas and refinery off-gas and said diluent liquid is water.
9. The process of claim 1 wherein the vaporliquid separator is selected from the group consisting of a flash vessel, a vertical drum, a horizontal drum, a fractionation column, a centrifugal separator and a cyclone.
10. The process of claim 9 wherein the vaporliquid separator is a flash vessel.
11. The process of claim 1 wherein the hydrogen-to-carbon atomic ratio of the C5+ portion of the pyrolysis products from each set of radiant coils is used to control the cracking severity in those coils.
12. The process of claim 11 wherein the hydrogen-to-carbon atomic ratio is determined by analyzing the ultra-violet absorbance of the C5+ portion of the pyrolysis products and by correlating the values of the resulting absorbance to the hydrogen-to-carbon atomic ratio of C5+ portion of the pyrolysis products from each set of radiant pyrolysis coils.
13. The process of claim 1 wherein said feedstock is a fully vaporizable wide boiling range feedstock, and wherein two vaporliquid separators are used in combination with the convection section of the furnace to form three separate vapor feedstocks for three sets of radiant pyrolysis coils.
14. The process of claim 1 wherein said feedstock is a fully vaporizable wide boiling range feedstock, and wherein three vaporliquid separators are used in combination with the convection section of the furnace to form four separate vapor feedstocks for four sets of radiant pyrolysis coils.
15. The process of claim 1 wherein said pyrolysis furnace has a single radiant cell.
16. The process of claim 1 wherein said pyrolysis furnace has two radiant cells.
17. A process for pyrolyzing a wide boiling range hydrocarbon feedstock or mixtures of hydrocarbon feedstocks having a wide boiling range, comprising a variety of hydrocarbons of differing carbonhydrogen ratios andor molecular weights and including undesirable high boiling point andor non-vaporizable components in an pyrolysis furnace having a convection section, least two sets of radiant pyrolysis coils, and a vapor distribution header in order to produce olefins and other pyrolysis products, comprising:
a. heating and partially vaporizing a feedstock, and feeding the partially vaporized feedstock to a vaporliquid separator device to produce fractions comprising separate vapor and liquid phases;
b. feeding the vapor phase to the vapor distribution header and then to a first set of radiant pyrolysis coils of a pyrolysis furnace operated at a first set of cracking conditions where the hydrocarbons are cracked to produce olefins;
c. heating the liquid phase from the first vaporliquid separator to a temperature sufficient to vaporize a portion of the hydrocarbons, feeding the heated two phase mixture to a second vaporliquid separator and separating the vapor phase fraction from the liquid phase fraction;
d. feeding the vapor phase from the second vaporliquid separator to the vapor distribution header and then to a second set of radiant pyrolysis coils of the olefins pyrolysis furnace operated at a second set of cracking conditions where the hydrocarbons are cracked to produce olefins;
e. removing the liquid phase fraction which contains undesirable andor non-vaporizable components from the second vaporliquid separator.
18. The process of claim 17 wherein said cracking conditions in the particular set of radiant pyrolysis coils includes feed rate, residence time, temperature history, heat input and dilution steam to feed ratio.
19. The process of claim 18 wherein the liquid phase from step e is removed and used as fuel oil, feedstock to a gasifier or feedstock to a coker.
20. The process of claim 18 wherein the liquid phase from step e is subjected to thermal cracking to produce additional hydrocarbon components having boiling points below 1000\xb0 F. (538\xb0 C.), which are subsequently vaporized and included in the feed to the second set of radiant pyrolysis coils, and the remaining liquid portion from the thermal cracking is removed and used as fuel oil, feedstock to a gasifier or feedstock to a coker.
21. The process of claim 17 wherein three vaporliquid separators are used in combination with the convection section of the furnace to form three separate vapor feedstocks for three sets of radiant pyrolysis coils.
22. The process of claim 17 wherein the vaporliquid separator is selected from the group consisting of a flash vessel, a vertical drum, a horizontal drum, a fractionation column, a centrifugal separator and a cyclone.
23. The process of claim 17 wherein the hydrogen-to-carbon atomic ratio of the C5+ portion of the pyrolysis products from each set of radiant coils is used to control the cracking severity in those coils.
24. The process of claim 23 wherein the hydrogen-to-carbon atomic ratio is determined by analyzing the ultra-violet absorbance of the C5+ portion of the pyrolysis products and by correlating the values of the resulting absorbance to the hydrogen-to-carbon atomic ratio of C5+ portion of the pyrolysis products from each set of radiant pyrolysis coils.
25. The process of claim 17 wherein said feedstock is selected from the group consisting of (i) short residue, (ii) long residue, (iii) desalted crude oil, (iv) oils derived from coal, shale oil and tar sands, (v) heavy component products from synthetic hydrocarbon processes selected from SMDS, gas to liquids, heavy paraffin synthesis and Fischer-Tropsch and (vi) heavy ends from hydrocrackate.
26. The process of claim 17 wherein said feedstock is short residue or vacuum tower bottom.
27. The process of claim 17 wherein said pyrolysis furnace has a single radiant cell.
28. The process of claim 17 wherein said pyrolysis furnace has two radiant cells.