WO2002042063A1 - Method for extending the useable life of a polyamide pipe liner during use in a water-oil-gas environment - Google Patents
Method for extending the useable life of a polyamide pipe liner during use in a water-oil-gas environment Download PDFInfo
- Publication number
- WO2002042063A1 WO2002042063A1 PCT/US2001/043837 US0143837W WO0242063A1 WO 2002042063 A1 WO2002042063 A1 WO 2002042063A1 US 0143837 W US0143837 W US 0143837W WO 0242063 A1 WO0242063 A1 WO 0242063A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- polyamide
- pipe
- sheath
- oil
- gas
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/34—Layered products comprising a layer of synthetic resin comprising polyamides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B1/00—Layered products having a general shape other than plane
- B32B1/08—Tubular products
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B15/00—Layered products comprising a layer of metal
- B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
- B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
Definitions
- the invention pertains to polyamide pipe liners used for the transport of oil or gas, and, more particularly, to a method for extending the useable life of a polyamide pipe liner that is used in a water-oil-gas environment.
- Polyamide (PA) materials are used as liners for a gas-oil-water barrier in pipes used to transport gas, oil water and mixtures thereof.
- the normal practice in the industry is to extrude a nylon sheath in the shape of a continuous tube of a thickness ranging from several millimeters to several centimeters. This tube will be the principal barrier containing the fulid under flow.
- a sacrificial layer several millimeters thick is extruded as a layer to protect the principal layer from mechanical friction (i.e., wear as it rubs against an internal metal carcass). The metal carcass prevents collapse of the piper from the sub-sea environment.
- a sacrificial layer may also be placed outside the principal PA layer to prevent friction wear of the principal layer with outer metal windings used to contain the often high internal pressures of the pipe which can be over 100 atmospheres.
- Prior art also shows the measurement of the molecular weight of PA using witness coupons or taking small samples of the PA liner as a means for monitoring aging of the PA liner.
- Molecular weight has been shown to be correlated with the PA liner's performance mechanical properties. See, for example, U.S. Patent 5,614,683 which is herein incorporated by reference.
- the major aging process causing degradation of polyamide (PA) when used as a pipe liner for the transport of oil, gas, and/or water has been found to be the result of two competing processes.
- Figure 1 is a graph showing the deterioration of molecular weight of a polyamide 11 sample over time at various temperatures in a 100% water environment for a relatively high molecular weight sample (77,000);
- Figure 2 is a graph showing an increase in the molecular weight of a polyamide 11 sample over time at various temperatures in a 100% water environment for a relatively low molecular weight sample (14,000);
- Figure 3 is a graph showing changes in molecular weight for a relatively high molecular weight polyamide 11 sample over time in different environments (e.g., dry oil (1% acid, dry), and oil-acid-water with increasing percentages of acid) at 115°C);
- environments e.g., dry oil (1% acid, dry), and oil-acid-water with increasing percentages of acid
- Figure 4 is a graph showing the changes in molecular weight of over time for a polyamide 11 sample over time which incorporates polyethylene glycol;
- Figure 5 is a cross-sectional view of a pipe typically used to transport oil or gas from a sub sea environment
- Figure 6 is a cross-sectional view of a pipe typically used to transport oil or gas above ground.
- Figure 2 shows the change in molecular weight of a lower molecular weight sample at these same temperatures and in the same environment. That is, in both Figure 1 and 2, the samples were stored in 100% water. In Figure 1, the sample had a starting molecular weight of 77,000, and in Figure 2, the sample had a starting molecular weight of 14,000. Figure 2, in contrast to Figure 1, shows that the molecular weight is increasing. Together, Figures 1 and 2 show the existence of processes which involve both chain scission and chain recombination during aging in a water- hydrolysis environment.
- Figure 3 shows the change in molecular weight of a relatively high molecular weight polyamide 11 sample in an oil-acid- water environment. Figure 3 shows a much slower rate of decrease in the molecular weight when less acid- water is present. Figure 3 also shows in a dry oil environment, the molecular weight exhibits a small increase in its value over time.
- Figures 1-3 demonstrate that the molecular weight of a polyamide can either decrease or increase depending on the environment in which it is used. This is the basis for the method of extending the life expectancy of a pipe liner used in a water-oil-gas environment through manufacturing design and material modification or operating procedures during use, such as filling the pipe with a hot drying agent or hot dry oil. Decreasing the amount of water present in the polyamide at any given temperature will increase the relative rate of chain recombination or polymerization and will decrease the relative rate of chain scission caused by hydrolysis. Decreasing the amount of water present in the polyamide tube liner can be controlled by several methods.
- One method involves constructing an inner sheath inside the principal piper liner which significantly reduces the diffusion of water in the polyamide barrier.
- suitable materials include fluorinated polymers such as tetrafluorinated polyethylene or polyvinyldifluoride.
- a second method involves modification to the polyamide structure which reduces water solubility in the polyamide. Examples of chemical modifications including adding moieties which reduce the concentration of water or solubility through copolymer, block polymer, graft polymer, polymer blends, or adding bulky or hydrophobic groups near the amide bond to create a modified polyamide chain.
- a third method involves use of additives in the pipe flow streams which complex and/or bind up the free water so that it does not diffuse into the polyamide sheath.
- a fourth method involves placing a drying agent in the pipe which reduces the water content in the polyamide sheath, and then allowing the pipe to heat up, as for example, by placing a hot dry oil in the pipe so the recombination rate can be made to exceed the rate of chain scission and the molecular weight of the polyamide (e.g., polyamide 11) can be increased.
- a drying agent such as, but not limited to sodium sulfate, calcium chloride, and magnesium sulfate.
- hot oil or hot oil with another liquid plus a dessicant such as sodium sulfate, calcium chloride, magnesium sulfate could be used to fill the pipe, with the desiccant serving the function of reducing or eliminating water from the pipe liner.
- a dessicant such as sodium sulfate, calcium chloride, magnesium sulfate
- Figure 4 shows that when the polyamide is exposed to ethylene glycol, a substance which is both a chain extender which can react with two polyamide chains tying them together with esterification, and also that can tie up water, the rate of degradation is decreased.
- a chain extender and/or water complexing agent such as ethylene glycol
- Figures 5 and 6 illustrate practical implementations of the claimed invention in pipes typically used to transport oil or gas in a sub sea environment or over ground, respectively.
- Figure 5 there is an inner metal carcass 10 and an outer metal sheath 12.
- Figure 6 there is no inner metal carcass, but there is an outer metal sheath 12.
- a sheath 14 impermeable to water, but not gas or oil is adhered to the inner surface of the polyamide barrier layer 16.
- This sheath 14 can be extruded separately or simultaneously with the polyamide barrier layer 16.
- the sheath 14 serves the function of reducing the permeation of water in the fluid flow within the pipe into the polyamide barrier layer.
- suitable sheath materials include but are not limited to polyvinylchloride (PVC), polyvinyldifluoride
- the polyamide barrier layer 16 acts as a barrier to the gas or oil being transported by the pipe.
- the sheath 14 and barrier layer 16 can each be on the order of several millimeters to several centimeters thick. In another embodiment of the invention the sheath 14 is eliminated.
- the polyamide barrier layer 16 is altered to be more resistant to water permeation, thereby reducing hydrolysis of the chemical backbone.
- a desiccant such as sodium sulfate, magnesium sulfate, or calcium chloride is incorporated into the polyamide barrier layer 16 during extrusion.
- the quantity of desiccant would be less than 10% by weight of the extruded material.
- the desiccant in the barrier layer 16 would bind up the water which permeates from the gas or oil into the barrier layer, and thereby reduce chain scission.
- the polyamide barrier layer 16 is a constructed as a copolymer such as a graft copolymer wherein hydrophobic side chains are covalently bonded to a backbone of a polyamide, a block copolymer wherein hydrophobic polymer chains are joined with the polyamide (e.g., alternating sections of the polymer would include polyamide and hydrophobic polymers), and polymer blends which include mixtures of hydrophobic polymers and polyamides.
- hydrophobic moieties such as halogens can be attached directly to the polyamide or to chains which are grafted to the polyamide.
- polymers such as PVC, PVDF, and PTFE might be used.
- a piece of aged polyamide liner having a molecular weight between 24,000 and 28,000 was placed in a dry hot air environment for six days. At 24,000 to 28,000 molecular weight, the polyamide liner is generally replaced since at this molecular weight it is no longer elastic and becomes brittle. After six days at 100°C, the polyamide liner material was rejuvenated to a level of 35,000 molecular weight. A similar piece of aged polyamide liner was treated for six days at 150°C and was rejuvenated to a higher molecular weight level. The high temperature may be driving off water that permeated into the polyamide as steam.
- the life expectancy of the polyamide barrier layer may be increased by periodic heat treatment such that moisture is driven out.
- hot air can be directed through the pipe to rejuvenate the polyamide barrier layer, or a hot dry oil or gas at a temperature sufficient to drive out water can be directed though the pipe, or another dry liquid or a combination of gas or oil and another dry liquid at a temperature sufficient to drive out water can be directed through the pipe.
- a desiccant or chain extender could be incorporated into the hot dry liquid directed through the pipe.
- the drying fluid will be of a sufficiently high heat capacity that it will allow adequate heating over the entire length of the polyamide liner when the fluid is injected at one end of the pipe (i.e., it will remain sufficiently warm to drive out water when it reaches the other end of the pipe).
- the pipe itself could include heating devices or hot air delivery devices used to heat a drying fluid and the polyamide material on a periodic basis.
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/432,525 US20040045620A1 (en) | 2001-11-23 | 2001-11-23 | Method for extending the useable life of a polyamide pipe liner during use in a water-oil gas environment |
BR0115681-0A BR0115681A (en) | 2000-11-24 | 2001-11-23 | Oil or gas conveying pipe, method for extending the life of a polyamide barrier layer in an oil or gas conveying pipe, method for rejuvenating a polyamide barrier layer used in a conveying pipe or gas, and method for extending the life expectancy of a polyamide material |
AU1672202A AU1672202A (en) | 2000-11-24 | 2001-11-23 | Method for extending the useable life of a polyamide pipe liner during use in a water-oil-gas environment |
EP01997207A EP1355779A4 (en) | 2000-11-24 | 2001-11-23 | Method for extending the useable life of a polyamide pipe liner during use in a water-oil-gas environment |
NO20032296A NO20032296L (en) | 2000-11-24 | 2003-05-21 | Method for Extending the Life of a Polyamide Stir Liner Using in a Water-Oil-Gas Environment |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US25258300P | 2000-11-24 | 2000-11-24 | |
US60/252,583 | 2000-11-24 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2002042063A1 true WO2002042063A1 (en) | 2002-05-30 |
Family
ID=22956624
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2001/043837 WO2002042063A1 (en) | 2000-11-24 | 2001-11-23 | Method for extending the useable life of a polyamide pipe liner during use in a water-oil-gas environment |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP1355779A4 (en) |
AU (1) | AU1672202A (en) |
NO (1) | NO20032296L (en) |
WO (1) | WO2002042063A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109595402A (en) * | 2018-12-10 | 2019-04-09 | 运城学院 | A kind of chemical industry equipment pipeline and its pipeline processing technique |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5038833A (en) * | 1985-03-22 | 1991-08-13 | Technoform Caprano+Brunnhofer Kg | Fuel line for fixed-length vehicle installation |
US5152323A (en) * | 1988-11-22 | 1992-10-06 | Allied Tube & Conduit Corporation | Plastic-lined pipe |
US5339867A (en) * | 1991-12-12 | 1994-08-23 | Itt Corporation | Composite metal tube and method of making the same |
US5500263A (en) * | 1993-04-02 | 1996-03-19 | Huels Aktiengesellschaft | Multilayer plastic pipe |
US6110550A (en) * | 1996-11-22 | 2000-08-29 | Institut Francais Du Petrole | Limited permeability sheath and application to pressure pipes |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IT222865Z2 (en) * | 1991-08-02 | 1995-05-08 | Mazzer Materie Plastiche | ANTI-STATIC PLASTIC TUBE FOR CONVEYING EVAPORABLE AND FLAMMABLE SUBSTANCES, IN PARTICULAR FOR VEHICLE FUEL SUPPLY SYSTEMS |
DE19823585A1 (en) * | 1998-05-27 | 1999-12-02 | Basf Ag | Composite element containing polyisocyanate polyaddition products |
DE29816278U1 (en) * | 1998-09-10 | 1998-12-10 | Pioflex Kunststoff In Form Gmbh | Plastic hose made up of several concentric layers |
-
2001
- 2001-11-23 AU AU1672202A patent/AU1672202A/en active Pending
- 2001-11-23 EP EP01997207A patent/EP1355779A4/en not_active Withdrawn
- 2001-11-23 WO PCT/US2001/043837 patent/WO2002042063A1/en not_active Application Discontinuation
-
2003
- 2003-05-21 NO NO20032296A patent/NO20032296L/en unknown
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5038833A (en) * | 1985-03-22 | 1991-08-13 | Technoform Caprano+Brunnhofer Kg | Fuel line for fixed-length vehicle installation |
US5152323A (en) * | 1988-11-22 | 1992-10-06 | Allied Tube & Conduit Corporation | Plastic-lined pipe |
US5339867A (en) * | 1991-12-12 | 1994-08-23 | Itt Corporation | Composite metal tube and method of making the same |
US5500263A (en) * | 1993-04-02 | 1996-03-19 | Huels Aktiengesellschaft | Multilayer plastic pipe |
US6110550A (en) * | 1996-11-22 | 2000-08-29 | Institut Francais Du Petrole | Limited permeability sheath and application to pressure pipes |
Non-Patent Citations (1)
Title |
---|
See also references of EP1355779A4 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109595402A (en) * | 2018-12-10 | 2019-04-09 | 运城学院 | A kind of chemical industry equipment pipeline and its pipeline processing technique |
Also Published As
Publication number | Publication date |
---|---|
AU1672202A (en) | 2002-06-03 |
NO20032296D0 (en) | 2003-05-21 |
NO20032296L (en) | 2003-05-21 |
EP1355779A4 (en) | 2005-03-09 |
EP1355779A1 (en) | 2003-10-29 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2956300B1 (en) | Use of semi-aromatic copolyamide for transporting refrigerant fluid | |
FR3076337A1 (en) | UNDERWATER FLEXIBLE DRIVING COMPRISING A MULTILAYER EXTERNAL SHEATH | |
RU2266309C2 (en) | Polyamide-based composition for flexible tubes contained crude oil or gas | |
CN103372986B (en) | Flexible pipe body and its manufacture method | |
JP7220568B2 (en) | Thermoplastic structure for transporting refrigerant fluids | |
FR2512165A1 (en) | FLEXIBLE PIPE RESISTANT TO HIGH PRESSURES FOR TRANSPORTING GAS AND LIQUIDS CONTAINING GAS | |
US20040045620A1 (en) | Method for extending the useable life of a polyamide pipe liner during use in a water-oil gas environment | |
RU2319887C2 (en) | Flexible pipe made of material including thermoplastic polymer and polyolefin and used in oil or gas field development (variants) | |
RU2224160C2 (en) | Multilayer pipe and system of pipes for water in water and heat supply systems | |
CA2620747C (en) | Pipes comprising hydrolysis resistant polyamides | |
JP2003227582A (en) | Plastic pipe reinforced in permeation preventing property | |
US20010021426A1 (en) | Unbonded flexible pipes and method for the production thereof | |
FR2663401A1 (en) | FLEXIBLE TUBULAR PIPE COMPRISING A CROSSLINKED POLYETHYLENE SHEATH, DEVICE AND METHOD FOR MANUFACTURING SUCH A PIPE. | |
US20050048239A1 (en) | Polymeric pipes and liners and fuel lines made from blends of fluoroppolymers and polyamides | |
US20080185065A1 (en) | Multilayer Pipe | |
JP4295274B2 (en) | Low-cost, low-permeability multilayer tube with an intermediate polymer alloy layer | |
EP1355779A1 (en) | Method for extending the useable life of a polyamide pipe liner during use in a water-oil-gas environment | |
AU746523B2 (en) | Unbonded flexible pipes and method for the production thereof | |
AU2002216722A2 (en) | Method for extending the useable life of a polyamide pipe liner during use in a water-oil-gas environment | |
CA2620157A1 (en) | Marine umbilical comprising hydrolysis resistant polyamides | |
BE1004682A3 (en) | Polyamide compositions and shaped objects from same. | |
US7696301B2 (en) | Marine umbilical comprising hydrolysis resistant polyamides | |
JP2008517814A (en) | Multi-layer pipe containing hydrolysis-resistant polyamide | |
EP3113944B1 (en) | Multilayer tube and use thereof for fluid transportation at medium pressure | |
CN108558281A (en) | A kind of seabed Sandwich pipeline and its special phase-change microcapsule |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PH PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2002216722 Country of ref document: AU |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2001997207 Country of ref document: EP |
|
REG | Reference to national code |
Ref country code: DE Ref legal event code: 8642 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 10432525 Country of ref document: US |
|
WWP | Wipo information: published in national office |
Ref document number: 2001997207 Country of ref document: EP |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 2001997207 Country of ref document: EP |
|
NENP | Non-entry into the national phase |
Ref country code: JP |
|
WWW | Wipo information: withdrawn in national office |
Country of ref document: JP |