Single Mechanical Seals
Balanced and unbalanced single mechanical seals for water, utility and general process pumps — built to spec in SiC, carbon and tungsten carbide.
Balanced & unbalanced · Type 1 / 2 / 21 · SiC / Carbon / TC · FFKM / EPDM / Viton · Custom
We are the manufacturer, not a reseller — we build in-house and supply at quantities that work for a distributor, an OEM or a maintenance department.
Balanced & unbalanced
for low- and high-pressure duty
Proven designs
Type 1, 2 and 21 component seals
Any face pair
SiC, carbon or tungsten carbide
When a single seal is the right call
- Clean, non-hazardous media — for water, coolant and benign process fluids a single seal is the simplest, most economical choice.
- Balanced for pressure — balanced single seals take higher stuffing-box pressure without the heat and wear an unbalanced seal suffers.
- Face pair matters — carbon/SiC for clean duty, SiC/SiC for mild abrasives; the wrong pair is the usual cause of early failure.
- Easy to standardize — Type 1, 2 and 21 are the workhorses; matching the original type keeps a fleet simple to maintain.
Hazardous or volatile duty instead? See when you need a double seal vs a single.
What we supply
Unbalanced and balanced single seals, OEM-compatible or custom — at the quantities your operation actually orders.
Unbalanced single seals
Type 1 and Type 2 single-spring and multi-spring seals for low-pressure water and utility pumps.
Balanced single seals
Type 21 and balanced designs for higher stuffing-box pressure and longer life on demanding duty.
OEM-compatible & custom
Drop-in equivalents to common single seals, or custom-machined to your shaft and stuffing-box dimensions.
Match the single seal to the duty
Type, face pair and elastomer follow the service. The table is a starting point; send the duty and we confirm.
| Service | Type | Face pair | Elastomer |
|---|---|---|---|
| Clean water | Unbalanced (Type 1) | Carbon / Ceramic | NBR / EPDM |
| Hot water / utilities | Balanced (Type 21) | Carbon / SiC | EPDM / Viton |
| Mild chemical | Balanced | SiC / SiC | Viton / FFKM |
| High pressure | Balanced | SiC / SiC | FFKM |
Go deeper: Balanced vs unbalanced · Single vs double.
Single Mechanical Seal FAQ
Balanced or unbalanced?
Unbalanced single seals suit low stuffing-box pressure; once pressure climbs a balanced seal runs cooler and lasts longer. We size it to your conditions.
Single or double seal?
Single seals are for clean, non-hazardous media. Hazardous, toxic or volatile duty needs a double seal.
Will it fit my pump?
We build to your shaft and stuffing-box dimensions and to Type 1, 2 and 21 envelopes — send the pump model or a sample.
What face materials?
Carbon/ceramic for clean water, carbon/SiC for utilities, SiC/SiC for mild abrasives and chemicals.
Source Single Mechanical Seals At Scale
OEM-compatible, custom-machined and private-label single seals built in-house to your spec, at low minimums. Send a pump model, a drawing or a sample and we’ll quote.