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Other Mechanical Seals — Specialty Range from Mumbai, India
Vacuum service, cryogenic-to-high-temperature swings, a reversible pump, or a duty that just doesn't fit a standard catalogue seal?
Alongside our core mechanical seal ranges, Ashish Seals India manufactures four specialty constructions that solve problems the standard designs don't: reverse balanced seals for vacuum and high-pressure duty, single acting balanced seals for crystallising and sludge-laden media, engineered balanced seals for extreme pressure and cryogenic-to-high-temperature service, and bi-directional seals for reversible pumps. We've been building these in Mumbai since 2005.
Each of these four exists because a standard single or double seal hits a limit somewhere — pressure, temperature, rotation direction, or a media that fouls a conventional face. Tell us where your duty sits and we'll tell you honestly which of these four actually solves it, rather than pushing the one that's easiest to sell.
Types of Other Mechanical Seals
Reverse Balanced Mechanical Seals
Externally mounted, multi-coil spring seals where liquid pressure itself is used to close the faces — useful for vacuum and high-pressure applications. Compact design needs no extra axial or radial installation space, and eliminates the shaft step or sleeve normally needed for balancing. Built to handle corrosive chemicals, hydrocarbons, and light or contaminated liquids.
View Reverse Balanced Seal →
Single Acting Balanced Seals
A standard design, independent of rotation direction, with springs placed outside the media so there's no shaft fretting. The unbalanced and balanced versions are achieved by simply altering the carbon face on its circlip — one platform, two duty levels. Suited to crystallising solutions, slurries and sludge across wastewater, sugar, pulp and pharmaceutical processes.
View Single Acting Balanced Seal →
Engineered Balanced Seals
Our most demanding-duty construction — balanced, inside mounted, independent of direction of rotation, built with multiple springs and a dedicated drive mechanism. Rated up to 150 bar and down to –140°C, purpose-built for oil pumps and boiler feed pumps where standard seals simply don't have the pressure or temperature headroom.
View Engineered Balanced Seal →
Bi-Directional Mechanical Seals
Standard, unbalanced, inside-mounted construction that runs equally well in either direction of rotation — the seal to specify when the pump itself is reversible. Handles chemical, water and slurry duty without needing a rotation-specific design.
View Bi-Directional Seal →Compare the Four: Specifications at a Glance
These four seals solve different problems and cover different operating envelopes. Use this table for a first shortlist — final selection always depends on your actual duty.
| Seal Type | Shaft Diameter | Pressure (max.) | Temperature | Rotation | Typical Duty |
|---|---|---|---|---|---|
| Reverse balanced | [Custom to application] | Vacuum & high-pressure duty | [Custom to application] | Independent of direction | Corrosive chemicals, hydrocarbons, vacuum service |
| Single acting balanced | [Custom to application] | [Custom to application] | [Custom to application] | Independent of direction | Crystallising solutions, slurries, sludge |
| Engineered balanced | 25 mm to 110 mm | 25 to 150 bar | –140°C to 180°C | Independent of direction | Oil pumps, boiler feed pumps |
| Bi-directional | 25 mm to 90 mm | Up to 14 bar | –25°C to 200°C | Reversible / bi-directional | Chemical, water, slurry |
The engineered balanced seal covers the widest pressure and temperature range of the four and is the one to consider first for cryogenic or high-pressure oil and boiler feed duty. If your requirement doesn't map cleanly onto any of these four, send us the details anyway — this range exists precisely for duties that don't fit a standard catalogue seal.
Which of the Four Do You Need?
Vacuum or high pressure, with liquid pressure available to help close the faces? Reverse balanced seal.
Crystallising, sludge-laden or slurry media where you want both balanced and unbalanced options on one platform? Single acting balanced seal.
Extreme pressure (up to 150 bar) or cryogenic-to-high temperature (–140°C to 180°C), typically on oil or boiler feed pumps? Engineered balanced seal.
A reversible pump that runs in either direction? Bi-directional mechanical seal.
What We Need to Quote Your Seal
These specialty constructions are matched to the duty that pushed you past a standard seal — the more precisely we understand that duty, the better the recommendation. Send as much of this as you can.
| Parameter | What to Send | Why It Matters |
|---|---|---|
| Equipment type | Pump, oil pump, boiler feed pump, or other rotating equipment | Sets duty class and expected loading |
| Shaft / sleeve diameter | Actual measured diameter at the seal | Sets internal dimensions |
| Rotation | Fixed direction or reversible | Rules bi-directional in or out |
| Pressure | Normal, maximum, and whether vacuum is involved | Points toward reverse balanced or engineered balanced |
| Temperature | Operating and extreme (including cryogenic) conditions | Rules out standard constructions if extreme |
| Media | Chemical name, corrosivity, crystallising or slurry tendency | Material compatibility and geometry choice |
| Reason a standard seal didn't work | Failure history, or why you're not using a standard single/double seal | Tells us which of the four actually applies |
| Existing seal | Model, drawing, photos, sample, failure history | Enables a compatible replacement |
| Order details | Quantity, delivery location, required date | Production and dispatch planning |
Industries We Serve
This specialty range goes wherever a standard seal hits a limit — pressure, temperature, rotation, or fouling media:
Why Buy from Ashish Seals India?
We've manufactured industrial sealing solutions in Mumbai since 2005, with the entire process under one roof:
Application-based seal selection by our own engineering team — we'll say if a standard seal is actually enough
Custom design and development, including reverse engineering from a worn sample
CNC and VMC machining, seal-face lapping [checked to light-band flatness]
Component inspection, assembly and testing before every dispatch
Extreme-duty capability — up to 150 bar and –140°C to 200°C across this range
[Repair and reconditioning of existing seals]
What that means for you as a buyer: one accountable manufacturer, a seal matched to the specific limit your standard seal hit rather than a generic "high-performance" part, and someone who picks up the phone when there's a question after delivery.
Frequently Asked Questions
What is a reverse balanced mechanical seal?
An externally mounted, multi-coil spring seal where liquid pressure is used to close the faces rather than oppose them — useful for vacuum and high-pressure applications, and compact enough to need no extra axial or radial installation space.
What is a single acting balanced seal?
A standard-design, single mechanical seal with springs placed outside the media, so there's no shaft fretting. The balanced and unbalanced versions are made from the same platform by altering the carbon face on its circlip.
What is an engineered balanced seal?
Our extreme-duty construction — balanced, with multiple springs and a dedicated drive mechanism, rated up to 150 bar and down to –140°C. Built for oil pumps and boiler feed pumps where standard seals don't have the pressure or temperature headroom.
What is a bi-directional mechanical seal?
A standard, unbalanced, inside-mounted seal built to run equally well in either direction of rotation — specified whenever the pump itself is reversible.
How do I know which of these four I need?
Start with what pushed you past a standard seal: vacuum or high pressure points to reverse balanced; crystallising or sludge media points to single acting balanced; extreme pressure or cryogenic temperature points to engineered balanced; a reversible pump points to bi-directional. Send us the details and we'll confirm.
What pressure and temperature can an engineered balanced seal handle?
Shaft diameters 25 mm to 110 mm, pressure 25 to 150 bar, and temperatures from –140°C to 180°C — the widest envelope of the four, built for oil and boiler feed pumps.
What pressure and temperature can a bi-directional seal handle?
Shaft diameters 25 mm to 90 mm, pressure up to 14 bar, and temperatures from –25°C to 200°C, for chemical, water and slurry duty.
Can a reverse balanced seal handle vacuum service?
Yes — this is one of its primary applications, along with high-pressure duty, since liquid pressure itself helps close the faces.
Can a single acting seal be converted between balanced and unbalanced?
Yes — both versions are made from the same platform, achieved by altering the carbon face assembled on its circlip.
Which materials are used for these specialty seals?
Ceramic, carbon, silicon carbide and tungsten carbide for the faces, with metal parts and elastomers selected for your specific pressure, temperature and media.
Can you manufacture a replacement from an old seal or sample?
Yes. We regularly develop replacements from a worn sample, a dimensional drawing, or good photographs plus the equipment details and operating conditions.
What is the price of these specialty mechanical seals in India?
It depends heavily on which of the four, plus shaft diameter, materials and quantity — there's no fixed price list. Send your pump and duty details for a specific quotation.
Do you supply outside Mumbai?
Yes — we supply across India [and export to the Middle East, Africa and Southeast Asia].
Request a Quote for a Specialty Mechanical Seal
A duty that doesn't fit a standard catalogue seal — extreme pressure, cryogenic temperature, vacuum service, or a reversible pump. Send us the equipment details, operating conditions and why your standard seal hasn't worked. Our engineers will confirm which of these four fits, with a quotation to follow.