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FLOWSERVE Mechanical Seal: Mechanical Shaft Seal, 51, 1 1/4 in Shaft Dia., 1.63 in Working Lg - Mechanical Shaft Seals
FLOWSERVEMechanical Shaft Seals

FLOWSERVE Mechanical Seal: Mechanical Shaft Seal, 51, 1 1/4 in Shaft Dia., 1.63 in Working Lg

The FLOWSERVE Mechanical Shaft Seal, type designation 51, is a single-spring mechanical seal with a carbon ring and Buna gasket. It features a 316 stainless steel spring and is designed for a 1 1/4-inch shaft…

SKU 3G-OTH-96966

Also listed as: 5112504 · 51 125 04

Brand
FLOWSERVE
Item
Mechanical Seal: Mechanical Shaft Seal, 51, 1 1/4 in Shaft Dia., 1.63 in Working Lg
Category
Mechanical Shaft Seals
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Technical Specifications

FLOWSERVE
Manufacturer Part Number
51-125-04
Type
51, 316
Shaft Dia.
1 1/4 in
Working Lg
1.63 in
Spring Type
Single Spring
Ring Material
Carbon
Gasket Material
Buna
Spring Material
316
Seal Type Designation
51

Technical Documents

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FLOWSERVE Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The FLOWSERVE Mechanical Shaft Seal, type designation 51, is a single-spring mechanical seal with a carbon ring and Buna gasket. It features a 316 stainless steel spring and is designed for a 1 1/4-inch shaft diameter with a 1.63-inch working length (MPN 51-125-04).

Frequently Asked Questions

What is the FLOWSERVE 51-125-04 mechanical seal used for?

The FLOWSERVE 51-125-04 mechanical shaft seal is used in industrial pumps and rotating equipment to prevent fluid leakage along a 1 1/4-inch shaft. It is suitable for applications requiring a single-spring design with a carbon ring and Buna gasket, such as water, chemical, and general process industries.

What are the specifications of the FLOWSERVE 51-125-04 mechanical seal?

The FLOWSERVE 51-125-04 mechanical seal has a 1 1/4-inch shaft diameter, 1.63-inch working length, single-spring design, carbon ring, Buna gasket, and 316 stainless steel spring. It is type designation 51 with manufacturer part number 51-125-04. These specs ensure reliable sealing in standard pump applications.

Where to buy the FLOWSERVE 51-125-04 mechanical seal worldwide?

You can source the FLOWSERVE 51-125-04 mechanical seal worldwide through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time on this FLOWSERVE mechanical shaft seal.

How to install a FLOWSERVE 51-125-04 mechanical seal?

To install the FLOWSERVE 51-125-04 mechanical seal, ensure the shaft and housing bore are clean and free of debris. Lubricate the Buna gasket and carbon ring with a compatible lubricant, then slide the seal onto the 1 1/4-inch shaft. Follow pump manufacturer guidelines for proper compression and alignment to avoid damage.

Used in

Common applications for FLOWSERVE
Water and wastewater pumping — FLOWSERVE Type 21 mechanical seal (e.g., MPN 21-100-10) for centrifugal pumps in municipal water treatment
Hydrocarbon processing — FLOWSERVE Type 68 mechanical seal (e.g., MPN 68-062-214) for diesel and light oil transfer pumps
Food processing — FLOWSERVE Type 21 seal (MPN 21-137-04) for cooking oil circulation pumps in edible oil refineries
Chemical transfer — FLOWSERVE Type 51 narrow cross-section seal (MPN 51-087-05) for compact chemical dosing pumps
HVAC and cooling systems — FLOWSERVE Type 16 unitized rotary seal (MPN 16-062-11) for chilled water pump shaft sealing
General industrial mixing — FLOWSERVE Type 52 narrow cross-section seal (MPN 52-125-05) for agitator shafts in batch processing tanks

FLOWSERVE Products

3G Electric supplies FLOWSERVE mechanical shaft seals. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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