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FLOWSERVE Mechanical Seal: Mechanical Shaft Seal, 21, 3/4 in Shaft Dia., 0.88 in Working Lg - Mechanical Shaft Seals
FLOWSERVEMechanical Shaft Seals

FLOWSERVE Mechanical Seal: Mechanical Shaft Seal, 21, 3/4 in Shaft Dia., 0.88 in Working Lg

The FLOWSERVE Mechanical Shaft Seal, designated Type 21, is a single-spring mechanical seal with a carbon ring and Buna gasket. It features an 18-8 spring material and is designed for a 3/4-inch shaft diameter with a…

SKU 3G-OTH-95236

Also listed as: 2107504 · 21 075 04

Brand
FLOWSERVE
Item
Mechanical Seal: Mechanical Shaft Seal, 21, 3/4 in Shaft Dia., 0.88 in Working Lg
Category
Mechanical Shaft Seals
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Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

FLOWSERVE
Manufacturer Part Number
21-075-04
Type
21, 18-8
Shaft Dia.
3/4 in
Working Lg
0.88 in
Spring Type
Single Spring
Ring Material
Carbon
Gasket Material
Buna
Spring Material
18-8
Seal Type Designation
21

Technical Documents

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

Product Description

The FLOWSERVE Mechanical Shaft Seal, designated Type 21, is a single-spring mechanical seal with a carbon ring and Buna gasket. It features an 18-8 spring material and is designed for a 3/4-inch shaft diameter with a 0.88-inch working length (MPN 21-075-04).

Frequently Asked Questions

What is the FLOWSERVE Type 21 mechanical seal used for?

The FLOWSERVE Type 21 mechanical shaft seal is used in industrial pumps and rotating equipment to prevent fluid leakage along a rotating shaft. It is suitable for water, light chemicals, and general process applications where a single-spring, carbon-versus-ceramic face seal is required.

What are the specifications of the FLOWSERVE 21-075-04 mechanical seal?

The FLOWSERVE 21-075-04 is a Type 21 mechanical shaft seal with a 3/4-inch shaft diameter and 0.88-inch working length. It features a carbon ring, Buna gasket, and 18-8 spring material with a single-spring design. The manufacturer part number is 21-075-04.

Where to buy FLOWSERVE mechanical seals worldwide?

You can source FLOWSERVE mechanical seals, including the Type 21, through 3G Electric. As a global industrial equipment distributor since 1990, 3G Electric handles full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time.

How to install a FLOWSERVE Type 21 mechanical seal?

To install a FLOWSERVE Type 21 mechanical seal, ensure the shaft and housing bore are clean and free of burrs. Lubricate the seal faces and gasket with a compatible fluid. Slide the seal onto the shaft, seat the stationary face, and secure the set screw. Follow pump manufacturer torque specs.

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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Cross-referenced by specification & description
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