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dry gas seals

8 mm to 13. of process gas by seal element analysis. gas seals have been running continuously for more than built and tested for Compared to conventional oil. When required. The total running lubricated seals.000 D-R gas seals are seals can help your currently in operation. manufacturing. pressures (up to 2. quality inspection. to provide Ingersoll-Rand began applying the best solution for each Because of their advantages. operation benefit from our product’s unique anti. This ■ retain pressure during design has been proving itself shutdown. D-R can been delivered or are currently selected to comply with NACE bring these advantages to your in production. and ability to offer Dresser-Rand gas seals have materials can be specially full-service solutions. on your centrifugal and gas production—both compressors to onshore and offshore. and speeds of success up to 48. advanced designs. and the ongoing the most experienced gas seal (procurement. even with the ever since in various compressor auxiliaries deactivated.DRY gas seals No one is better qualified to ■ improve efficiency— sometimes dramatically—by eliminating the parasitic power losses caused by oil shear and drag designs. refineries. The standard materials experience. chemical plants. and bidirectional designs D-R cartridge-type dry 95% of new compressors for Ingersoll-Rand began using are available for your needs gas seals comply with API varied services throughout the gas seals in process gas and process requirements. maintenance associated manufacturers in the industry. Thanks to our extensive compressors. world. Close Dresser-Rand dry gas to 1. In 1982. using advanced engineering methods and tools bring this superior technology ■ eliminate contamination such as CAD systems and finite to your equipment. gas Upgrading the gas seals liquefaction. 50. Some D-R standards. D-R gas seals are available in hang-up and high-reliability a range of dimensions (2 in / features. double).9 mm). dry gas seals: optimum performance experience now exceeds 10 and long life ■ eliminate the need for million hours with no “hang- D-R gas seals are manufactured complex and costly seal oil ups.) with them of our ISO 9000-certified MAKING A GOOD manufacturing and quality IDEA EVEN BETTER organizations. the technology in natural gas application. In 1995. and testing. dates back to the 1970s when tandem.000 rpm. as well as Our dry gas seal experience various arrangements (single. we drew on our extensive experience to develop our own gas seal technology. Both unidirectional dry gas seals are installed on lift compressors. more than 1. To ensure Not content with existing product performance and .600 of conditions. 617 requirements.900 a track record psi / 200 bar). accommodate a large range state-of-the-art manufacturing Since 1996. existing centrifugal compressor.5 in / 342. sealing applications such as gas transmission. etc.” That makes D-R one of using the resources systems. 11 years. D-R created lubricants a special patented rotor groove ■ eliminate contamination of pattern and carbon ring pusher seal oil by the process gas design that maximize reliability ■ extend the life of lubricating oil in all operating conditions.

performance. a dedicated D-R Gas Seals Business Unit manages the complete inboard production process. Typically. full-service D-R's unidirectional patented pattern At the heart of every gas seal is a pair of rings. fixed to the case. allow reverse rotation. and seal systems Other Material Options: design/technology work closely O-Rings—Silicone or Polymer Seal together to optimize each Barrier Seal—Aluminum Labyrinth system and ensure an efficient Other materials available on a upgrade with minimal downtime. D-R’s patented innovations ensure consistent performance. custom. D-R’s Rotating Seat: experts in rotor dynamics. a static test is Designed for reliability performed. required Spring: Inconel physical characteristics and Barrier Seal: Carbon Ring fit for existing cavities. Safety. support. engineering process gas to be contained.client satisfaction. case-by-case basis. create a dynamic gas pumping or “lifting” effect that installation. and start. fixed to the shaft by springs and pressure. pushes the spring-loaded stationary ring away from the up supervision for all seal rotating ring. the grooves on the rotating ring compressor modifications. thermodynamics. gas seal upgrades. After reassembly. is introduced into the seal has additionally been designed to capabilities and direct technical area. We take into account the crucial aspects Metallic Components 410 (NACE Compliant) of each application. . O Ring: Aflas performance and reliability are Stationary Seat: Carbon all carefully considered. filtered compressor discharge provide experienced project gas. Centrifugal compressor seals are a critical subsystem that must be carefully integrated into the overall unit design. The temperature. including compression service. Gas Path pressure and flow rate at each seal connection are measured and recorded with calibrated instruments over the full range outboard of rated operating speeds and pressures. creating a very small gap. is held against a rotating rotating seal face provides excellent Dresser-Rand is your single- ring. reduced to a pressure slightly above that of the D-R's bidirectional patented pattern management. of the faces creates a “dam” region where the gas pressure is broken down to the flare or the vent pressure. Rotating Seat Every D-R gas seal is subjected to a complete set of tests. The seals are then disassembled and inspected. The inner portion upgrades. Tungsten Carbide (Shrouded) or Silicon Carbide aerodynamics. as requested. The fully equipped test rig includes Stationary Ring a test vehicle in which a pair of gas seals (CW = Clockwise and CCW = Counter Clockwise) Compressor is tested under contractual Shaft conditions. We handle total procurement. We the outer portion. As the shaft rotates. The acting lift-off effect and optimum gas film source solution for dry face of the rotating ring incorporates special grooves on stiffness at both low and high speeds. from initial consultation through final testing. A solutions of short and long grooves on the stationary ring. inspection.

Reverse rotation can still occur in abnormal situations or in some specific processes (closed Dresser-Rand L-Ring loop systems) and only bidirectional seals can Design: Lowest Risk of withstand reverse rotation at maximum pressure and “Hang-Up” maximum speed.” equipment (for instance. check valve position).) without contact between the faces. “Hang-Up” INTERNAL DIA. For The first seal at the back a given gap. If O-ring friction prevents the spring from functioning. Reverse rotation can between the L-ring and cartridge does not change significantly Bidirectional often be avoided by the proper with operating conditions. low pressure. It must be noted that unidirectional Our patented design seals have some significant ability to withstand places the second O-ring reverse rotation for a short period of time and at low in the L-ring instead of speed. in actual applications it can develop a flaw: friction can cause the o-ring to stick. while keeping the OD Seal Design: A Risk of leakage rate at an acceptable level. to an externally imposed variation of the gap.” The reliability of the seal depends upon its ability to accommodate sudden disturbances Improved Design with (vibrations. between the rings and the potential for process gas leakage. A good design will have sufficient film thickness to Standard Dry Gas provide the best possible reliability. Dresser-Rand recommends keeping more O-ring groove. A thicker gas the rotating ring. inner diameter in clearance gap)). a condition known as “hang-up. The resulting increase in the closing force is than one seal on hand in inventory to minimize generally sufficient to eliminate “hang-up. the gas film thickness preventing the springs to push the stationary ring toward defines the distance between the faces. OF This design uses a single Both unidirectional and bidirectional designs have GROOVES their own advantages. sliding face of the O-ring is transferred to the bottom of the however. gas film thickness also increases the leakage rate. the seal can remain open (due to dirt. Unidirectional thus better reliability than seal. When the seal is rotating. etc. or “hang up.” resulting in too wide a gap film reduces the risk of contact between the faces. This provides the advantages A bidirectional seal is the same at both ends of the mentioned above plus compressor (to prevent incorrect assembly). unidirectional groove patterns provide O-RINGS of the carbon ring is in a three to five times greater gas film stiffness than relatively high-temperature bidirectional patterns.” operational risk. High Less Risk of “Hang-Up” gas film stiffness enables the seal to better react This design uses two O-rings. increasing D-R’s patented design solves this problem. bidirectional groove patterns. only the spring force closes the seal. Which design should low risk of “hang-ups” you choose? As elegant as the gas seal solution is. so there is less risk of a high-friction seal. environment. in the cartridge. Having an important benefit: if the O-ring sticks to the housing. for instance). the the same seal at both ends makes it interchangeable. However. . In operating mode ID the closing forces (springs BD plus pressure between ■ U  nidirectional seal groove outer diameter and balance patterns are known to provide diameter equalize the greater gas film thickness opening forces (pressure gradient between outer diameter and and higher gas film stiffness. design and installation of process condition and “hang-up. O-ring. thereby increasing reliability. The radial clearance of rotation. Both the and most obvious advantage is its cartridge and L-ring are manufactured of steel (same thermal ability to operate in either direction expansion coefficient and Young’s modulus). In the absence of pressure. The second O-ring is fitted into the bore ■ The bidirectional gas seal’s first of the seal cartridge in a lower-temperature location. shocks due to process L-Shaped Pushing Ring: upsets. surge.

Dynamic testing. with authorized factory parts and testing to restore them to their original condition. Brazil gas seal repair and static test facility. Brazil and Cilegon.S. is performed when major parts are replaced. Static testing is always performed on refur- bished seals. Seals removed from service for any reason should be returned to the nearest service center for disassembly. simulating running conditions of pressure and speed. France gas seal Indonesia stand ready to service D-R gas seals repair and test facility. Le Havre. Le Havre. The gas seal repair and test facilities at the Dresser-Rand Service Centers in Houston. Cilegon. set of seals to ensure a quick change-out with minimal down time.TEST facilities Complete gas seal maintenance and testing available in the U. . Indonesia gas seal repair and static test facility. Texas gas seal We recommend that each installation has a spare repair and test facility. France. and Brazil. ready for the next change-out. Houston. Campinas. Campinas. Texas. France. Indonesia. The restored seals will be repackaged as an assembly and returned in their original shipping container.. clean-up and test- ing.

Contact Dresser-Rand for detailed design and engineering information suitable to your specific applications.A. France Tel: (Int'l +33) 2-35-25-5225 Email: info@dresser-rand. For more information on dry gas seals.S. France USA Brazil.A. 2100 Cedex 7013 Houston. Lázaro Gonçalves de Oliveira. visit www. Texas 77042 Houston. Dresser-Rand Dresser-Rand do Brasil 31 Boulevard Winston Churchill 1415 Lumpkin Road Av. 13458-626 Tel: (Int'l +33) 2-35-25-5225 Tel: (Int'l +1) 713-346-2257 Tel: (Int'l +55) 19 3728.4200 – Operations For a complete list of products and services. This brochure comprises a general overview of the Dresser-Rand products described herein. It is solely for informational purposes. Suite 1000 Dresser-Rand Asia Pacific Sdn Bhd 10205 Westheimer Road 10205 Westheimer Road Unit 9-4. Paris 75784 France 31 Boulevard Winston Churchill Tel: (Int’l +33) 156 26 71 71 Cedex 7013 Fax: (Int’l +33) 156 26 71 72 Le Havre 76080. Avenue Kleber (Europe. TX 77043 Santa Barbara d’Oeste Le Havre 76080. does not represent a warranty or guarantee of the information contained herein.dresser-rand.A.8600 – Services Fax: (Int'l +33) 2-35-25-5366/5367 Fax: (Int'l +1) 713-827-0353 Tel: (Int'l +55) 19 3459. Texas 77042 Bangunan Malaysian Re Tel: (Int'l +1) 713-354-6100 Tel: (Int’l +1) 713-354-6100 17 Lorong Dungun Fax: (Int'l +1) 713-354-6110 Fax: (Int’l +1) 713-354-6110 Damansara Heights 50490 Kuala Lumpur. Printed in U. Form 85189-14 Bringing energy and the environment into or contact us at: Dresser-Rand S. 9th Floor Houston.® . visit Fax: (Int'l +33) 2-35-25-5366/5367 ©2014 Dresser-Rand. and is not to be construed as an offer to sell or solicitation to buy. Dresser-Rand reserves the right to modify its products and related product information at any time without prior notice. Middle East & Africa) Fax: (Int'l +60) 3-2093-2622 Cedex 16 Dresser-Rand S. DRESSER-RAND is a registered trademark of Dresser-Rand Company. Malaysia Dresser-Rand EMEA Tel: (Int'l +60) 3-2093-6633 112. Suite 1000 West8 or contact the following: CORPORATE Headquarters Regional Headquarters Dresser-Rand The Americas Asia-Pacific West8 Tower.