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Custom and Replacement Seals for Reactors & Process Vessels

Reactor Mechanical Seal Manufacturer in Mumbai, India

Running a glass-lined or stainless steel reactor that needs a seal built for real batch conditions — not a catalogue part guessed from vessel size?

Ashish Seals India manufactures application-specific reactor mechanical seals for glass-lined, SS316 and mild-steel reactors across single, double, top-entry, bottom-entry, horizontal-mount and dry-running arrangements. We've been building mechanical seals in Mumbai since 2005, and reactor duties are one of the most demanding jobs we handle — the seal has to survive heating, cooling, vacuum and pressure all within the same batch, in shaft sizes from [20 mm to 200 mm].

A reactor seal is built around the same principle as an agitator mechanical seal, but the duty is harder: the vessel cycles between vacuum and pressure, hot and cold, clean and fouled, several times a day. A seal sized only for the nameplate pressure rating will fail the first time the batch goes off-recipe. So we don't quote from vessel volume alone — send us the full batch profile and we'll size the seal for the worst condition it will actually see, not the average one.
Reactor mechanical seal manufactured by Ashish Seals India
Engineered To OrderBuilt for Your Batch Profile, Not Just Vessel Size
CertifiedISO 9001:2015 Certified
ExperienceManufactured in Mumbai Since 2005
FabricationIn-House CNC Machining, Lapping & Testing
FlexibilityCustom & Replacement Seals

Types of Reactor Mechanical Seals

Reactor mechanical seal manufactured by Ashish Seals India

Single Reactor Mechanical Seal

One set of sealing faces — the economical choice where the process fluid presents little to no risk to the environment and conditions stay within moderate pressure and temperature. Common on general-purpose SS reactors and non-hazardous batch chemistry.

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Reactor mechanical seal manufactured by Ashish Seals India

Double Reactor Mechanical Seals

Two sets of faces with a barrier or buffer fluid between them, giving a second stage of containment for toxic, flammable or solvent-based reactions, and for reactors that swing between vacuum and pressure within the same batch.

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Reactor mechanical seal manufactured by Ashish Seals India

Top Entry Reactor Mechanical Seals

Mounted above the reactor, shaft hanging down through the manway or nozzle into the batch. The standard arrangement on glass-lined and SS reactors alike — and the position where shaft deflection through heating and cooling cycles matters most.

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Reactor mechanical seal manufactured by Ashish Seals India

Bottom Entry Reactor Mechanical Seals

Fitted at the base of the reactor, close to the outlet nozzle — where product settling, solids and residue at the faces are the main design concern. Used where the process or discharge arrangement calls for a lower-mounted drive.

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Reactor mechanical seal manufactured by Ashish Seals India

Horizontal Mount Entry Reactor Mechanical Seals

Fitted where the shaft enters through the side wall of a horizontal reactor or kettle. Radial loading and the product level at the seal drive the design — typical on horizontal reaction vessels and specialised batch equipment.

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Reactor mechanical seal manufactured by Ashish Seals India

Dry Running Mechanical Seals

Purpose-built for reactors where the process fluid presents little to no risk to the environment and no liquid reaches the faces — most often top-entry reactors running above the batch level. Face combination and temperature decide whether a dry-running design will hold up.

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Every double reactor seal works together with a barrier-fluid support system. See our thermosyphon pot systems — we supply the seal and its support system as a matched pair.

What We Need to Quote Your Reactor Seal

Reactor seals are built around the vessel and the batch, not picked off a shelf. The more of this you can send, the faster and more accurate the quotation — but don't hold back an enquiry because a few rows are blank. Photographs of the existing installation fill many of the gaps.

ParameterWhat to SendWhy It Matters
Reactor typeGlass-lined, SS316, mild-steel lined, or other constructionSets material compatibility and nozzle/flange standard
Entry positionTop, bottom, or horizontal mountDetermines orientation and drive arrangement
Reactor capacityWorking volume in litresIndicates shaft length and expected torque
Shaft diameterActual shaft or sleeve diameter at the sealSets face, sleeve and internal dimensions
Nozzle / manway dimensionsOD, PCD, bolt count, pilot, mounting depthNeeded for gland and cartridge design
Installation spaceAvailable height above the reactor, clearanceAvoids clashes with the drive or platform
Agitator speedNormal and maximum RPMAffects heat generation and face choice
RotationCW, CCW or reversibleDirectional vs bidirectional design
Design pressure / vacuumNormal, maximum, and whether the batch cycles between the twoSets seal balance and support needs
Temperature profileHeating, holding and cooling range across the batch, plus CIP/SIPDrives face, elastomer and metal choice
Process mediaChemical name(s), concentration, pHMaterial compatibility
Batch behaviourClean, sticky, abrasive, crystallising, polymerising, foamingChanges geometry and flushing
ViscosityAt start, mid-batch and end of reactionDrag and product movement at the seal
Solids%, particle size, abrasivenessFace materials and clearances
Batch cycleBatches per day, cycle time, number of heating/cooling swingsIndicates thermal and mechanical fatigue on the seal
Shaft runoutMeasured at the seal location, if knownExcess runout is a leading leak cause
Leakage riskNon-hazardous, toxic, volatile, flammableSingle vs double decision
LubricationDry, product, liquid or gas barrierHow the faces are cooled
Existing sealModel, drawing, photos, sample, failure historyEnables a compatible replacement
Order detailsQuantity, delivery location, required dateProduction and dispatch planning

Typical builds cover pressures up to [XX bar], vacuum down to [full vacuum], and temperatures from [–20 °C to 250 °C], depending on the material combination. Final limits are stated on the approved design.

Choose the Right Reactor Mechanical Seal

Use this table for a first shortlist. The final choice always comes down to your media, pressure or vacuum swing across the batch, temperature profile, and how strictly leakage has to be controlled.

Seal TypeBest Suited ForTypical ApplicationsLubricationEntry Position
Single reactor sealNon-hazardous process fluid, moderate pressure and temperatureGeneral SS reactors, low-risk batch chemistryDry-running or product-lubricatedTop, bottom or horizontal
Double reactor sealToxic, volatile or solvent-based reactionsGlass-lined reactors, pharma and agrochemical batchesBarrier or buffer fluidTop, bottom or horizontal
Top-entry reactor sealStandard glass-lined and SS reactor drivesChemical, pharma and agrochemical reactorsDry, liquid or gas-supportedTop entry
Bottom-entry reactor sealLower-mounted drive arrangementsReactors with bottom-driven agitationProduct or barrier-fluid lubricatedBottom entry
Horizontal-mount reactor sealHorizontal reaction vessels and kettlesSpecialised batch and blending equipmentBarrier or buffer fluidHorizontal (side) entry
Dry-running reactor sealProcess fluid presents little to no environmental riskTop-entry reactors running above batch levelDry-running face combinationMainly top entry

Where your specification calls for standard envelopes, we work to [EN 12756 / DIN 24960 dimensions and DIN 28138 reactor and agitator seal requirements].

Industries We Serve

Reactor mechanical seals go wherever a rotating agitator shaft enters a pressurised, vacuum-rated or contamination-sensitive reaction vessel:

Agitator mechanical seal manufactured by Ashish Seals India
ChemicalBatch and continuous reactors, solvent-based reactions
Agitator mechanical seal manufactured by Ashish Seals India
Pharmaceutical & Bulk DrugsAPI and bulk drug reactors, GMP-compliant builds
Agitator mechanical seal manufactured by Ashish Seals India
Dyes and PigmentsColour-intermediate synthesis and finishing reactors
Agitator mechanical seal manufactured by Ashish Seals India
PetrochemicalProcess reactors handling hydrocarbon and volatile streams
Agitator mechanical seal manufactured by Ashish Seals India
Food and NutraceuticalReaction and extraction vessels with CIP/SIP-compatible builds

Why Buy from Ashish Seals India?

We've manufactured industrial sealing solutions in Mumbai since 2005, with the entire process under one roof:

1

Application-based seal selection by our own engineering team, sized for your batch profile

2

Custom design and development, including reverse engineering from a worn sample

3

CNC and VMC machining, seal-face lapping [checked to light-band flatness]

4

Component inspection, assembly and testing before every dispatch, including hydro testing

5

Matched thermosyphon and barrier-fluid systems supplied with the seal

6

[Repair and reconditioning of existing seals]

Frequently Asked Questions

What is a reactor mechanical seal?

It's the seal that controls leakage where a rotating agitator shaft passes through the wall of a reactor or process vessel. It has to hold through the pressure, vacuum and temperature swings that happen across a single batch.

How is a reactor seal different from an agitator seal?

The two overlap heavily — a reactor seal is an agitator seal built for the extra stress of batch processing. The difference is the duty cycle: a reactor seal has to survive repeated swings between vacuum and pressure, and heating and cooling, within the same batch, not just steady-state running.

Should I use a single or double reactor seal?

Single where the process fluid presents little to no risk to the environment and pressure stays moderate. Double where the reaction involves toxic, volatile or solvent-based media, or where the vessel cycles between vacuum and pressure and any leakage to atmosphere is unacceptable.

When is a double mechanical seal required for a reactor?

Whenever leakage to atmosphere must be kept to an absolute minimum, or the batch involves hazardous solvents, toxic intermediates or vacuum distillation stages where a single seal can't hold a reliable barrier.

Does a double reactor seal need a thermosyphon pot?

Most liquid-lubricated double reactor seals do — the barrier fluid has to circulate, stay cool and stay monitored through every heating and cooling cycle. We supply the pot and the seal as a matched pair.

Can a reactor seal handle both vacuum and pressure in the same batch?

Yes, provided it's designed for that swing from the start. Tell us the full pressure and vacuum range the batch goes through — not just the nameplate rating — and we'll size the seal for the worst condition, not the average one.

What is a dry-running reactor seal used for?

It's used where the process fluid presents little to no risk to the environment and no liquid reaches the faces — typically top-entry reactors running above the batch level. Face material and temperature decide whether a dry-running design will hold up.

Can a reactor seal be fitted to a glass-lined reactor?

Yes. Glass-lined reactors have fixed nozzle and manway dimensions set by the vessel manufacturer, so send us the nozzle drawing and existing seal details and we'll build the seal to match rather than asking you to modify the vessel.

What is a horizontal-mount entry reactor seal?

A seal fitted where the shaft enters through the side wall of a horizontal reactor or kettle, rather than from the top or bottom. Radial loading and product level at the seal drive the design.

Can you manufacture a replacement from an old seal or sample?

Yes. We regularly develop replacements from a worn sample, a dimensional drawing, or even good photographs plus the equipment details and batch conditions.

Which materials are used for reactor seals?

Carbon, silicon carbide and tungsten carbide for the faces; SS 316/316L for metal parts; FKM, EPDM, PTFE or FFKM for the secondary seals, chosen for solvent and temperature compatibility across the full batch cycle.

Why does my reactor seal keep failing after a few batches?

The usual causes: the seal was sized for average conditions instead of the worst pressure/vacuum/temperature swing in the batch, thermal fatigue from repeated heating and cooling, barrier-pressure problems, or the wrong face material for the solvent. Send us the batch profile and failure history and we'll identify the likely cause before quoting a replacement.

What is the price of a reactor mechanical seal in India?

It depends on reactor type, single or double configuration, entry position, materials and any barrier-fluid system — there's no standard price list. Send your reactor and batch details for a specific quotation.

How long does a custom reactor seal take to manufacture?

Typically [X–Y weeks] depending on materials and complexity. Repeat orders against an approved drawing ship faster. Share your required date with the enquiry and we'll confirm.

Do you supply reactor seals outside Mumbai?

Yes — we supply across India [and export to the Middle East, Africa and Southeast Asia].

What details do you need for a quotation?

Reactor type, capacity, entry position, shaft diameter, nozzle dimensions, design pressure/vacuum, temperature profile, process media, batch cycle and existing seal details. See the table above — and if some of it is missing, send photos and we'll work from there.

Request a Quote for a Reactor Mechanical Seal

New reactor, existing vessel, or a seal that keeps failing after a handful of batches — send us the vessel drawing, existing seal details and full batch profile. Our engineers will review the application and recommend the seal configuration, materials and support arrangement, with a quotation to follow.