Press Release Summary:
ThermoflexÂ® velocity strings are lined with FortronÂ® polyphenylene sulfide, which reduces friction to gas flow, lowers pressure drop, and provides resistance to acids and hydrocarbons. They also contain polyaramid fiber layer with Nylon 6 extruded over it and have smooth surface that lessens paraffin build-up. Inert products withstand brines, condensates, and hydrocarbons; come in 1 to 2 3/8 in. dia; and withstand temperatures to 250Â°F.
Original Press Release:
PolyFlow Gas-Well Velocity String Uses Fortron® PPS to Cut Pressure Drop and Gain Corrosion Resistance
Summit, New Jersey; Kelsterbach, Germany, Dec. 17, 2003 - PolyFlow, Inc. has improved the performance of its Thermoflex® velocity strings for natural gas wells compared to steel velocity strings by lining them with Fortron® polyphenylene sulfide (PPS) from Ticona, the technical polymers business of Celanese AG (NYSE: CZ; FSE: CZZ). The extruded inner layer of Fortron® PPS reduces friction to gas flow, which lowers pressure drop, and provides better resistance to acids and hydrocarbons and less paraffin build-up.
In operating a gas well, the velocity of the gas-water mixture pumped must remain above a critical value so water does not drop out, fill the bottom of the well, and halt production. Pipe liners called "velocity strings" are inserted into well casings to boost the speed of the rising mixture by narrowing the casing diameter. Steel has traditionally been used in this application, but polymer pipe has begun to supplant steel.
"The Fortron® PPS lining makes a real difference," says Jay Wright, PolyFlow's President. "It is about 100 times smoother than steel, so the gas-water mixture flows faster in casings lined with it, and it causes less pressure drop. In one case, a Thermoflex® velocity string with an inside diameter of 1.4 inch (3.6 cm) in an 8,050-ft. (2,454 meters) well raised productivity from 150-to-165 thousand cubic ft. per day (mcfd) to 200-to-240 mcfd."
"The lining's smooth surface practically eliminates paraffin buildup," says Wright, "so our Fortron® PPS-lined pipe is rarely clogged by this material. By contrast, wells with steel strings must be shut down periodically for paraffin removal. Thermoflex® plastic pipe also weighs less and is more flexible than steel, so it is easier to install."
Wright also notes that Fortron® PPS is highly inert and withstands the brines, condensates, hydrocarbons and sour environments often found in gas wells better than steel. Steel pipe generally has a one-to-four-year life in gas wells because of exposure to the carbonic and sulfuric acids present in them.
Thermoflex® strings withstand temperatures to 250° F (120°C) and are much better thermal insulators than steel. Thermoflex® plastic pipe and steel pipe have thermal conductivities of 31 and 333 BTU in./hr/ft²/°R, respectively. Higher gas temperatures help prevent the condensation of water and hydrocarbons and so reduce backpressure on the formation, which is critical in low-pressure wells.
Thermoflex® velocity strings are made by a multilayer extrusion process using engineered polymers and fiber reinforcement. In addition to the inner Fortron® PPS lining, Fortron® PPS or nylon 6 are good candidates for us as an outer layer in severe environments for corrosion and abrasion resistance. The strings also contain a polyaramid fiber layer (both in braided form and as longitudinal strands) that increases burst and tensile strength. Nylon 6 is extruded over the polyaramid fiber for added strength.
Thermoflex® strings come in several diameters between 1 and 2-3/8 inch (2.5 and 6.0 cm) that match standard piping sizes. A 1-inch diameter string weighs 0.17 lb/ft (0.25 kg/m) and can be used down to 20,000 ft. (6,100 meters), while a 2-3/8 inch string weighs 0.75 lb/ft (1.1 kg/m) and can be used down to 12,000 ft. (3,660 meters).
Thermoflex® strings are installed at rates of up to 100 ft/min. (30.5 m/min.). They come in continuous lengths of up to 6,000 ft. (1,830 meters), but special stainless steel splices allow any length to be used in the field. Since the piping has nearly one-tenth the weight of steel, smaller coiled tubing injectors often can be used, e.g., 20,000 pound (9,100 kg) "pup" units. The tubing also takes tighter bends than steel and works well in confined spaces.
PolyFlow also uses Fortron® PPS linings in other petroleum production piping to gain protection in corrosive and high-temperature environments. These piping products include casing liners, gathering liners, pipe liners, carbon dioxide injection lines, repair strings and work lines.
Additional Information Available
For information on Fortron® PPS, contact: Ticona, 90 Morris Avenue, Summit, New Jersey, 07901, USA. Phone: 1-800-833-4882 or 1-908-522-7500. Email: firstname.lastname@example.org. In Europe: Ticona GmbH, Professor-Staudinger-Strasse, D-65451 Kelsterbach, Germany. Phone: +49-(0)180-584-2662 (DE) or +49-(0)693-051-6299 (EU). Email: email@example.com. Or visit: www.ticona.com.
For information about PolyFlow's Thermoflex® velocity strings and other products, contact: PolyFlow, Inc., 2280 West Drive, P.O. Box 434, Oaks, Pennsylvania, 19456, USA. Phone: 1-610-666-5150. Or visit: www.polyflowinc.com.
PolyFlow, Inc. designs and manufactures fluid delivery systems for a wide variety of applications, including pipes, tubes and liners for oil and gas production. It is headquartered in Oaks, Pennsylvania, near Philadelphia. It also has an office in Belgium to serve markets in Europe, North Africa and the Middle East. For more information, see: www.polyflowinc.com.
About Ticona and Celanese
Ticona, the technical polymers business of Celanese AG, Kronberg, Germany, produces and markets a broad range of engineering polymers and achieved sales of Euros 757 million in 2002. Ticona has approximately 2,400 employees at production, compounding and research facilities in the USA, Germany and Brazil.
Celanese AG is a global chemicals company with leading positions in its key products and world class process technology. The Celanese portfolio consists of five main businesses: Acetyl Products, Chemical Intermediates, Acetate Products, Technical Polymers Ticona and Performance Products.
In 2002, Celanese generated sales of around Euros 4.3 billion and had 10,700 employees. The company has 24 production plants and six research centers in 10 countries mainly in North America, Europe and Asia. Celanese AG shares are listed on the Frankfurt stock exchange (stock exchange symbol CZZ) and on the New York Stock Exchange (symbol CZ).
For further information about Ticona and Celanese, please visit our websites: www.ticona.com and www.celanese.com.