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Type 28AT

Type 28AT
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TYPE 28 DRY-RUNNING, NON-CONTACTING GAS SEALS Technical Specification Standard Unidirectional Groove Design Product Description Type 28 compressor dry-running gas seals have been the industry standard since the 1970s for gas-handling turbomachinery. Utilizing John Crane's patented spiral groove pattern, these seals are non-contacting in operation. • During dynamic operation, the mating ring/seat and primary ring/face maintain a sealing gap of approximately 0.0002 in./5 microns, thereby eliminating wear • These seals eliminate seal oil contamination and reduce maintenance costs and downtime • Single, double opposed, and tandem cartridge seals are capable of handling a wide variety of gas sealing applications in the gas collection/transmission, refining, chemical and petrochemical processing industries Optional Bidirectional Groove Design Design Features • Shrouded mating ring prevents secondary damage in the event of a mating ring fracture • Low-level leakage can be vented to a safe area, used as fuel to drive equipment, or returned to process via a low-pressure ejector Performance Capabilities • Temperature: Up to 6,500 psi(g)/450 bar(g) across single stage

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TYPE 28 DRY-RUNNING, NON-CONTACTING GAS SEALS Technical Specification Type 28AT Tandem Arrangement

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Inlet for Filtered Seal (or Process) Gas MATING RING PRIMARY RING Outlet for 1st Stage Leakage and Buffer Gas Inlet for Buffer Gas (Optional) MATING RING Outlet for 2nd Stage Leakage and Separation Gas Separation Seal contact John Crane for options BEARING CAVITY Polymer Secondary Seal *Typical Application pressures up to 2,650 psi(g)/180 bar(g) PRIMARY RING Interstage Labyrinth TYPE 28 Technical Specification Type 28XP Tandem Arrangement DRY-RUNNING, NON-CONTACTING GAS SEALS

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Seal (Or Process) Gas Labyrinth Inlet for Filtered Seal (or Process) Gas MATING RING PRIMARY RING Outlet for 1st Stage Leakage and Buffer Gas Inlet for Buffer Gas (Optional) MATING RING Outlet for 2nd Stage Leakage and Separation Gas Separation Seal contact John Crane for options BEARING CAVITY Polymer Secondary Seal *Typical Application pressures up to 2,650 psi(g)/180 bar(g) PRIMARY RING Interstage Labyrinth TYPE 28 Technical Specification DRY-RUNNING, NON-CONTACTING GAS SEALS

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Seal (Or Process) Gas Labyrinth Inlet for Filtered Seal (or Process) Gas MATING RING PRIMARY RING Outlet for 1st Stage Leakage and Buffer Gas Inlet for Buffer Gas (Optional) Outlet for 2nd Stage Leakage and Separation Gas Separation Seal contact John Crane for options BEARING CAVITY Technical Specification Type 28EXP Tandem Arrangement DRY-RUNNING, NON-CONTACTING GAS SEALS Advanced Polymer Secondary Seal *Typical Application pressures up to 3,250 psi(g)/220 bar(g) PRIMARY RING 2ND STAGE MATING RING Interstage Labyrinth

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TYPE 28 DRY-RUNNING, NON-CONTACTING GAS SEALS Technical Specification Typical Single Seal Arrangement and Seal Support System *Single Seal Arrangement for applications not requiring a safety back-up seal. Typical Double Opposed Seal Arrangement and Seal Support System VEN T *Double Seal Arrangement where hazardous gas is not permissible to leak into atmosphere. Typical Tandem Seal Arrangement and Seal Support System VEN T *Tandem Seal Arrangement for applications requiring a safety back-up seal.

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TYPE 28 DRY-RUNNING, NON-CONTACTING GAS SEALS Technical Specification Size and Speed Effect on Leakage Conditions: Air, 1,200 psig/83 bar g 5 Leakage (SCFM) Leakage (sl/min) Seal Size Pressure, Temperature and Gas Effect on Leakage Conditions: 6.187-inch Diameter Seal, 14,000 rpm 5 125 100 3 Leakage (sl/min) Leakage (SCFM) Gas Seal Power Consumption Conditions: Air, 140°F/60°C 5 Seal Size *This information should not be used for specification purposes. Contact DryGasSeals@johncrane.com for more information about exact application requir

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TYPE 28 DRY-RUNNING, NON-CONTACTING GAS SEALS Technical Specification North America United States of America Tel: 1-847-967-2400 Fax: 1-847-967-3915 Europe United Kingdom Latin America Brazil Middle East & Africa United Arab Emirates Asia Pacific Singapore If the products featured will be used in a potentially dangerous and/or hazardous process, your John Crane representative should be consulted prior to their selection and use. In the interest of continuous development, John Crane Companies reserve the right to alter designs and specifications without prior notice. It is dangerous to smoke...

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