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FLOWSERVE Mechanical Seal: Mechanical Shaft Seal, 21, 1/2 in Shaft Dia., 0.81 in Working Lg - Mechanical Shaft Seals
FLOWSERVEMechanical Shaft Seals

FLOWSERVE Mechanical Seal: Mechanical Shaft Seal, 21, 1/2 in Shaft Dia., 0.81 in Working Lg

The FLOWSERVE Mechanical Shaft Seal, designated Type 21, is a single-spring mechanical seal with a carbon ring and a Viton gasket. It features an 18-8 spring material and is designed for a 1/2-inch shaft diameter…

SKU 3G-OTH-94979

Also listed as: 2105005 · 21 050 05

Brand
FLOWSERVE
Item
Mechanical Seal: Mechanical Shaft Seal, 21, 1/2 in Shaft Dia., 0.81 in Working Lg
Category
Mechanical Shaft Seals
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

FLOWSERVE
Manufacturer Part Number
21-050-05
Type
21, 18-8
Shaft Dia.
1/2 in
Working Lg
0.81 in
Spring Type
Single Spring
Ring Material
Carbon
Gasket Material
Viton
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 a Viton gasket. It features an 18-8 spring material and is designed for a 1/2-inch shaft diameter with a 0.81-inch working length (MPN 21-050-05).

Frequently Asked Questions

What is the FLOWSERVE Type 21 mechanical seal used for?

The FLOWSERVE Type 21 mechanical 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-ring seal with Viton gasket provides reliable sealing.

What are the specifications of the FLOWSERVE 21-050-05 mechanical seal?

The FLOWSERVE 21-050-05 mechanical seal has a 1/2-inch shaft diameter, 0.81-inch working length, single spring type, carbon ring, Viton gasket, and 18-8 spring material. It is designated Type 21 and manufactured by FLOWSERVE under MPN 21-050-05.

Where to buy the FLOWSERVE 21-050-05 mechanical seal worldwide?

You can source the FLOWSERVE 21-050-05 mechanical seal through 3G Electric, a global industrial equipment distributor. We handle 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, then slide the seal onto the shaft. Follow the manufacturer's instructions for setting the working length and tightening the set screw.

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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