Flowserve ISC2 API 682 Cartridge Mechanical Seal

Overview

Flowserve ISC2 is a cartridge-mounted, API 682-compliant mechanical seal built to control leakage and extend mean time between repairs on centrifugal pumps handling hydrocarbons, chemicals, and general process fluids. As a cartridge design, the ISC2 arrives pre-assembled, pre-set, and dimensionally verified at the factory, which removes the setting errors that are the single most common cause of premature seal failure when a component-style seal is fitted in the field. Both balanced pusher and metal bellows configurations are available under the ISC2 family, and the seal is qualified to API 682 Category 1, 2, or 3 depending on the service class, so it can be specified directly against refinery and petrochemical engineering standards without a non-standard exception.

As a regional supplier of Flowserve products, Seven Star LLC supplies the ISC2 mechanical seal to industrial buyers across Oman and the wider GCC, with application engineering support delivered from within the region. Refinery turnaround teams in Sohar, petrochemical operators in Sur, and general process plants throughout Muscat rely on this traceable supply chain to source correctly configured ISC2 seals for their exact pump models and service conditions.

Operating Principle

The Flowserve ISC2 works as a rotating and stationary seal face pair held in continuous contact by spring or bellows load plus hydraulic pressure from the sealed fluid, forming a thin fluid film at the faces that provides both lubrication and the primary sealing barrier. In a balanced pusher configuration, a secondary O-ring or elastomer seal slides along the shaft or sleeve to compensate for face wear and thermal growth, while in a metal bellows configuration a welded metal bellows performs the same compensating function without any secondary elastomer, which is the preferred choice for high-temperature or chemically incompatible services where an elastomer would degrade.

Because the ISC2 is supplied as a complete cartridge with its own sleeve, gland, and setting clips, the axial face load is fixed at the factory to the correct value for the specified operating conditions before the seal ever reaches site. The installer simply mounts the cartridge on the pump shaft, removes the setting clips once the gland is bolted up, and the seal is ready for service — there is no field measurement, no spring compression gauge, and no risk of an incorrectly set face load that would otherwise shorten seal life or cause an immediate leak on startup.

Engineering Design of the Flowserve ISC2

Mechanically, the Flowserve ISC2 cartridge integrates the seal chamber, gland plate, sleeve, and seal faces into a single pre-assembled unit that bolts directly onto the pump’s stuffing box cover, matching the mounting dimensions of the pump manufacturer’s original seal chamber. The design supports single, dual unpressurized, and dual pressurized (API 682 Arrangement 1, 2, and 3) configurations, so the same base cartridge platform can be specified for straightforward hydrocarbon duty or upgraded to a fully contained dual-seal arrangement with an external barrier or buffer fluid system for zero-emission or highly hazardous service.

Face materials are selected from carbon, reaction-bonded silicon carbide, and tungsten carbide combinations to match the abrasiveness and lubricity of the process fluid, while secondary seals and gaskets are available in Viton, Kalrez, PTFE, and other elastomer or polymer grades chosen for chemical compatibility. The cartridge’s gland incorporates quench, flush, and drain ports as standard so it can be piped to any of the standard API 682 piping plans without modification, giving turnaround planners a predictable, repeatable installation across an entire pump fleet.

Key Features

The ISC2 combines cartridge convenience with the configuration range needed to meet refinery and petrochemical sealing standards. Its key features include:

• Factory pre-set, pre-assembled cartridge construction that eliminates field setting errors.
• API 682 qualification across Category 1, 2, and 3 service classes for direct specification against refinery engineering standards.
• Available as balanced pusher or metal bellows seal types for standard or high-temperature/chemically aggressive duty.
• Single, dual unpressurized, and dual pressurized (Arrangement 1, 2, 3) configurations from one common platform.
• Face material options including carbon, reaction-bonded silicon carbide, and tungsten carbide.
• Standard quench, flush, and drain gland ports compatible with all standard API 682 piping plans.
• Elastomer and polymer secondary seal choices including Viton, Kalrez, and PTFE for broad chemical compatibility.
• Dimensionally interchangeable with the original seal chamber, simplifying upgrade from packing or an older seal design.

Industrial Applications

The Flowserve ISC2 mechanical seal is specified wherever a centrifugal pump must contain hydrocarbons, chemicals, or process fluids to a strict emissions or safety standard. The Flowserve ISC2 is selected for typical duties that include crude and refined product transfer in refineries, feedstock and intermediate handling in petrochemical plants, boiler feedwater and condensate service in power and utility plants, and general process transfer in chemical manufacturing where fugitive emissions control is a regulatory requirement.

As the trusted supplier for Flowserve, Seven Star LLC supplies the ISC2 cartridge seal to refining and petrochemical operators across the Sohar and Salalah economic zones, power generation and desalination plants throughout the Sultanate of Oman, and process industries across the wider GCC. Because the ISC2 is dimensionally interchangeable with the original equipment seal chamber on most ANSI and API pump platforms already installed regionally, Seven Star LLC can supply exact-fit replacement cartridges and spare parts kits without requiring the pump itself to be modified.

Technical Specifications

The Flowserve ISC2 table below summarizes the principal design and application parameters, and every Flowserve ISC2 unit supplied by Seven Star LLC is built to this specification.

Request a Quote for Flowserve ISC2

For the Flowserve ISC2, Seven Star LLC invites refinery turnaround teams, EPC contractors, and rotating equipment engineers in Oman and across the GCC to submit a formal RFQ for the Flowserve ISC2 API 682 cartridge mechanical seal. Common configurations and spare parts kits are supplied on request with lead time confirmed at quotation, technical datasheets are available on request, and our instrumentation and rotating equipment division can advise on seal arrangement, face material, and piping plan selection for your specific pump and process fluid. In Oman and the GCC, Seven Star LLC guarantees genuine factory-warranted seals, certified spare parts, and locally based technical support for every ISC2 supplied.

Browse the full Flowserve range or see more Pumps products supplied by Seven Star LLC in Oman and the GCC.