Pusher Seals

+GENERAL PURPOSE +CAN BE LOWER COST +HIGH PRESSURE +HIGH SPEED +AXIAL DAMPING OF GASKET: BENEFICIAL FOR LIGHT HYDROCARBONS -GASKET MATERIAL & TEMPERATURE LIMITATIONS -CAN BE MORE SENSITIVE FOR HANG-UP DEPENDING ON APPLICATION

Pusher seals incorporate secondary seals, called the dynamic gasket, that are axially pushed by springs along the shaft or sleeve to compensate for seal face wear or wobble due to misalignment. Pusher seals -except for high duty versions- are generally less expensive than bellow designs and come in more sizes. The pusher seal is often chosen for light hydrocarbons, high pressure and high speed applications because of the inherently greater strength of the design and the axial damping action of the dynamic gasket. However pusher seals do not allow graphite gaskets and therefore maximun temperatures are limited by the available elastomer or PTFE gasket materials. Chemical attack of the gasket material can alsobe a limiting factor. In addition build-up from weepage across the seal faces can keep the secondary seals from moving axially on the shaft, thus robbing it of its ability to compensate for face wear (hang-up). The most common spring arrangement uses a number of small, highly corrosion resistant, springs. To Protect the small springs from contamination some designs position the springs outside the product. Alternatively a large single spring is used, that is better suited to harsh duties and dirty product. A last design which is often used is the so-called 'wavy spring,' which allows to build axially very compact designs.

84/85 SERIES PRESSURE: TO 400 psi TEMPERATURE: TO 400 F SPEED: TO 3000 fpm STD SIZES: 1" TO 7" Single multi-spring pusher cartridge seal suited for services in chemical applications, water treatment, and pulp and paper mills. This off-the-shelf, simple to install cartridge features a floating stationary face assembly to prevent face distortion during assembly and springs isolated from the pumpage for non-clogging operation. 86/87 SERIES PRESSURE: TO 400 psi TEMPERATURE: TO 400 F SPEED: TO 3000 fpm STD SIZES: 1" TO 7" Double multi-spring pusher cartridge seal suited for services in chemical applications, water treatment, and pulp and paper mills. This off-the-shelf, simple to install cartridge features a floating stationary face assembly to prevent face distortion during assembly and springs isolated from the pumpage for non-clogging operation. ALLPAC 2039 PRESSURE: TO 360 psi TEMPERATURE: TO 430 F SPEED: TO 4500 fpm STD SIZES: 33, 43, 53 AND 65mm Single, balanced multi spring seal designed according the metric DIN 24960 standard to L1k. Though a balanced seal it can be used on a straight shaft, with springs are mounted outside the product, without gasket sleeve wear. The seal uses two 100% identical faces. This seal is applied on a wide range of duties, primarily in the chemical industry where DIN standard pumps are used. ALLPAC N PRESSURE: TO 360 psi TEMPERATURE: TO 430 F SPEED: TO 4500 fpm STD SIZES: 30, 40, 50, 60mm Single, tandem or double balanced wavy spring seal cartridge designed according the metric DIN 24960 form C. Each seal face pair uses two 100% identical faces. When used as a double seal the inboard seal is reverse pressurized and therefore very resistant to clogging. This seal is designed specifically for the so-called 'form C' part of the DIN standard, and is therefore available only in four sizes. CRO PRESSURE: TO 300 psi TEMPERATURE: TO 500 F SPEED: TO 4500 fpm STD SIZES: 3/4" TO 4-1/2" Double, friction drive single spring pusher seal that can be used in moderate pressure applications with water or similar viscosity product. Seal depends on friction between dynamic gasket and pump shaft for drive. Metal parts of the seal are isolated from pumped product to prevent possible chemical or abrasive attack. Very easy to install. D PRESSURE: TO 1000 psi TEMPERATURE: TO 400 F SPEED: TO 4500 fpm STD SIZES: 0.525" TO 5.400" Balanced rotating single spring seal for the power industry or other high pressure applications. The design is identical to the U seal, except for the pumpring slots in the rotating face. Using an API plan 23 system to keep the seal cool, this seal is used in hot water and flashing hydrocarbon applications. DHTW PRESSURE: TO 2500 psi TEMPERATURE: TO 400 F SPEED: TO 15000 fpm STD SIZES: 1-5/8" TO 12" Balanced, stationary multi-spring seal, designed for power industry or other high pressure / high speed applications. Using an API plan 23 system, this seal is used in hot water applications. This seal is always carefully analyzed and tuned for balance and low face deformation for critical applications. EROPAC 600 PRESSURE: TO 150 psi TEMPERATURE: TO 430 F SPEED: TO 4500 fpm STD SIZES: 10mm TO 100mm Single, unbalanced single wavy spring seal designed according the metric DIN 24960 standard to L1k. This seal is applied on a wide range of duties, primarily in the chemical industry where DIN standard pumps are used. HDHW PRESSURE: TO 2500 psi TEMPERATURE: TO 400 F SPEED: TO 15000 fpm STD SIZES: 2" TO 6-1/2" Balanced, stationary multi-spring seal, designed for pipeline industry or other high pressure/ high speed applications. The seal design resembles the UHTW type, uses a different stationary face back-up ring, allowing a more compact design. This seal is always carefully analyzed and tuned for balance and low face deformation for critical applications. HSC/HSH PRESSURE: TO 1200 psi TEMPERATURE: TO 400 F SPEED: TO 12500 fpm STD SIZES: 1.5" TO 10" Balanced, flexible stator, multi-spring pusher design for use in high pressure high speed applications. This seal is boundary lubricated for long seal life. P-200 PRESSURE: TO 400 psi TEMPERATURE: TO 450 F SPEED: TO 4500 fpm STD SIZES: 1" TO 3-7/8" Economical, cartridge mounted, double multi spring pusher design combines value with ease of installation. Unitized construction and balanced design make the P-200 an ideal choice for a wide range of demanding services in general industry including chemical processing, pulp and paper, water treatment, and sewage plant applications. P-50 PRESSURE: TO 300 psi TEMPERATURE: TO 300 F SPEED: TO 3000 fpm STD SIZES: 1" TO 4" Single multi-spring pusher cartridge seal excellent for numerous services in chemical processing, water treatment and sewage plants, and pulp and paper mills. Pre-set cartridge design speeds installation, eliminates chance of installation error. Very easy to repair. Springs are mounted on stationary portion of seal to reduce contamination and forgive seal misalignment. PSS PRESSURE: TO 100 psi TEMPERATURE: TO 250 F SPEED: TO 3200 fpm STD SIZES: 1.5" TO 6" Split, single inside seal for pumps. Pre-assembled, unitized construction makes installation & repair easy and foolproof. Excellent for many non-hazardous services in chemical processing, pulp & paper, power generation and waste water treatment. High runout PSS-A version available for mixers and other equipment where teardown is a problem. QB PRESSURE: TO 750 psi TEMPERATURE: TO 400 F SPEED: TO 4500 fpm STD SIZES: 0.411" TO 5.911" Balanced multi-spring pusher seal for general service, primarily applied in the petrochemical and chemical industry. The QB(Q) complies fully with all requirements of API 682 type A. QBB/QB PRESSURE: TO 220 psi TEMPERATURE: TO 400 F SPEED: TO 4500 fpm STD SIZES: 1.750" TO 4.250" A QB version designed for reversed pressure operation. Fully compliant all requirements of API 682 type A arrangement 3, but with an extended pressure range. RO PRESSURE: TO 300 psi TEMPERATURE: TO 500 F SPEED: TO 4500 fpm STD SIZES: 3/8" TO 4-1/2" Single, unbalanced multi-spring seal used for general purpose mainly in the chemical industry. Individual parts are completely interchangeable and easy to replace. Can be used as an inside or outside seal in abrasive and corrosive services. UC PRESSURE: TO 1000 psi TEMPERATURE: TO 400 F SPEED: TO 4500 fpm STD SIZES: 0.566" TO 5.838" Balanced rotating single spring seal for heavy duty applications and general services. The UC seal has sufficient flexibility and clearance to compensate for minor misalignment of the shaft and bearings, while incorporating a state of the art encapsulated graphite gasketed silicon carbon rotating face. The UC seal's canned face provides optimum face flatness for low level emissions control

©1998-2000 Sealing Specialists & Service Company
turso@sealingspec.com