Precision engine valves,
engineered to run.
Antra Auto Tech forges, machines and heat-treats intake & exhaust valves, guides and seats for automotive, diesel and industrial engines - manufactured in Rajkot, India and exported to OEM and aftermarket partners in 35+ countries.
Antra engine valves, boxed and ready for the counter
Intake and exhaust valves in bright-finish and black-finish variants, forged and machined in Rajkot and packed in sealed Antra Industries retail boxes. Every box carries the Antra mark, the part reference and an Antra Power Rewards card with its own one-time code.
- Genuine Antra parts for 2 & 3-wheeler engines, plus passenger, commercial, tractor and industrial fitments
- Tamper-evident retail packaging with printed part reference
- Reward code inside every box - register it and earn a point
Manufacturer names are used for identification and fitment reference only. Antra Auto Tech is an independent manufacturer of aftermarket replacement parts and is not affiliated with, authorised by or endorsed by any vehicle manufacturer.
Three decades of precision, one Rajkot facility
Since 1992, Antra Auto Tech has forged, machined and heat-treated engine valves from a single manufacturing base in Metoda G.I.D.C., Rajkot - supplying OEM production lines and aftermarket buyers in 35+ countries. Every process stage stays under one roof, from raw steel to finished, inspected valve.
Valve treatments, and what each one is for
Where a valve wears depends on where it runs. These are the treatments applied to the seat, the tip, the stem and the head - specified per part, never left ambiguous.
surface treatment
resistance
resistance
at the head
Built for OEM & replacement buyers who can't afford downtime
In-house forging to finish
Every process stage - forging, machining, heat treatment, coating, grinding - stays under one roof for tighter tolerance control.
100% dimensional inspection
Every batch is measured against OEM drawings before it ships, not sample-checked.
OEM cross-reference library
500+ documented part-number cross-references across passenger, commercial and off-highway engines.
Export-ready documentation
Mill certs, material traceability and inspection reports packaged with every export shipment.
Custom engineering support
Reverse-engineering from sample or drawing for valves not in any catalog.
34 years of metallurgy know-how
Three decades focused on one product family - valves - not a diversified parts catalog.
Engineered across five vehicle & engine segments
Passenger Vehicles
Commercial Trucks
Tractors & Off-Highway
Two & Three-Wheelers
Forging checknear-net shape
CNC machining checkin-process
Profile checkseat & radius
Roundnessstem & head
Surface roughnessRa, stem finish
Dimension drawingvs. OEM specControlled at every stage, not checked at the end
A valve that looks right on the outside can still fail if the material, heat treatment or tolerance is off. We verify at each stage rather than relying on a final inspection to catch problems.
- Incoming raw steel verified against grade and composition before production
- 100% of batches dimensionally inspected against OEM drawings - not sample-checked
- Hardness and heat-treatment logged per batch for traceability
- Material test certificates and inspection reports ship with every export order
Three decades of building one product family - right.
Antra Auto Tech started as a small valve workshop in Rajkot in 1992. Today it's a specialist engine-valve manufacturer serving OEM and aftermarket buyers across 35+ countries - still focused on the one component family we've always made.
A specialist, not a generalist
While many auto-parts exporters spread across dozens of component categories, Antra Auto Tech has stayed narrow on purpose: intake and exhaust valves, valve guides, and valve seat inserts. That focus is what lets a mid-size manufacturer compete on the same drawings as much larger, diversified suppliers - every forging die, heat-treatment cycle and inspection gauge on our floor exists to serve one job.
We supply both OEM production lines and the aftermarket/replacement channel, with documented cross-references that let buyers match an Antra part to the OEM number they already know.
Quality built into the process, not checked at the end
We don't treat engine valves as a commodity part. A valve that fails under heat cycling or seat wear doesn't just cost a customer money - it costs them trust. That's why every batch we produce goes through the same four stages.
Material verification
Confirming steel grade and composition before machining begins.
Precision machining
Holding tolerances that match or exceed OEM drawings.
Heat treatment & hardening
Tuned to the specific valve application - passenger, diesel, two-wheeler, marine, and more.
Dimensional & visual inspection
At in-process and final stages, not just at the end of the line.
From workshop to export manufacturer
Founded in Rajkot, Gujarat
Started as a precision valve workshop serving the local automotive replacement market.
Moved into in-house heat treatment & machining
Brought forging, CNC machining and heat-treatment stages under one roof to tighten tolerance control.
First export shipments
Began supplying aftermarket distributors outside India, starting the current 35+ country export network.
OEM & aftermarket, five vehicle segments
Serving passenger, commercial, tractor, two-wheeler and industrial-engine customers with 500+ documented valve variants.
Three principles behind every batch
Precision over volume
We'd rather ship a smaller batch that's fully inspected than a larger one that isn't.
Documented traceability
Material certs and inspection records travel with every shipment - no exceptions for export orders.
Long-term partnerships
Most of our export relationships are repeat buyers, not one-off orders - we plan capacity around that.
Engine valves, guides, seat inserts and steering bearings - OEM and custom.
500+ documented valve variants plus guides, seat inserts and 2 & 3-wheeler steering bearing sets - cross-referenced to OEM part numbers wherever available.
Engine Valves - Intake & Exhaust
EN/DIN and JIS-grade alloy steel intake and exhaust valves for passenger, commercial, tractor, two-wheeler and industrial engines. Nimonic, bimetallic and Stellite-faced options for sustained high-temperature exhaust duty; bright and black finish.
Valve Guides
Precision-bored guides that hold the valve stem true through its full stroke - supplied matched to Antra valve SKUs or independently, to OEM bore and length.
Valve Seat Inserts
Seat inserts machined to a press-fit interference for cylinder-head repair and remanufacture, sized to the matching Antra valve head.
Steering Bearings
Steering-head bearing sets for 2 & 3-wheelers - cone races, caged ball retainers and lock nuts, boxed as a complete kit under the Antra mark.
Custom & Reverse-Engineered Valves
Send a sample, drawing or worn part - our engineering team reverse-engineers dimensions and metallurgy for valves that aren't in any catalog.
OEM production & aftermarket replacement
Production-line supply
Drawing-based production runs against your specification, with PPAP-style documentation on request.
Aftermarket replacement
Cross-referenced part numbers matched to the OEM valve your customers already ask for by name.
Custom / low-volume
Reverse-engineering and short-run production for legacy engines and niche applications.
Additional valve-train components
Beyond valves, guides and seats, we can source or supply the following components alongside your order - confirm current availability with our team.
Valve Springs & Retainers
Tappets / Lifters
Push Rods
Rocker Arm Components
Valve Cotters / Collets
Engine valve materials - grades, properties & applications.
A quick-reference guide across our intake steels, exhaust steels & superalloys, performance alloys, and seat/tip hardfacing materials. Tell us your engine specification and we'll confirm the right grade for your application.
Grades built for stem & tip wear resistance
| Material | Overview | Key Properties | Typical Applications |
|---|---|---|---|
| SUH3 (Silchrome 1) | The standard hardened steel grade for intake valves, built for stem/tip wear resistance rather than extreme heat. | High hardness · good fatigue resistance · cost-effective | Passenger cars, two/three-wheelers, general-purpose engines |
| SUH11 (Silchrome XB) | A harder, more wear-resistant step up from SUH3 for demanding intake applications. | Higher hardness · resists temper softening | High-performance and higher-RPM intake valves |
| EN8 / EN19 | General engineering steels for light-duty, cost-sensitive valve applications. | Adequate strength · good machinability | Small stationary engines, low-cost aftermarket |
Grades matched to the heat of the exhaust cycle
| Material | Overview | Key Properties | Typical Applications |
|---|---|---|---|
| EN52 | A cost-effective exhaust steel for moderate-temperature service. | Moderate hot strength (~650-700°C) · economical | Two/three-wheelers, naturally aspirated passenger vehicles |
| 21-2N | A mid-tier exhaust grade bridging EN52 and 21-4N. | Balanced hot strength and cost | Mid-displacement passenger & commercial vehicle exhaust valves |
| 21-4N | The industry-standard exhaust valve steel across automotive and diesel applications. | Strong hot strength (~700-750°C) · proven track record | Passenger cars, commercial vehicles, agricultural engines |
| Nimonic 80A | A superalloy for exhaust duty beyond what steel grades can reliably handle. | Superior high-temp strength · excellent creep resistance | Turbocharged/supercharged engines, heavy-duty diesel |
| Nimonic 90 | A cobalt-enhanced superalloy reserved for the most extreme thermal duty. | Higher creep strength than 80A | Extreme motorsport, specialty industrial engines |
| Inconel 751 | A functional equivalent to the Nimonic family, common in OEM programs. | High-temp strength and creep resistance | High-performance and OEM exhaust valve programs |
For reciprocating mass reduction
| Material | Overview | Key Properties | Typical Applications |
|---|---|---|---|
| Titanium Alloy (Ti-6Al-4V) | A lightweight valve material used to cut reciprocating valvetrain mass. [[confirm active product line]] | ~45-55% the density of steel · high strength-to-weight | Motorsport, racing, high-RPM performance builds |
Applied to the contact face, not the valve body
| Material | Overview | Key Properties | Typical Applications |
|---|---|---|---|
| Stellite | The premium hardfacing alloy for seat recession resistance. | Exceptional hot hardness · outstanding wear/galling resistance | Exhaust valve seat facing, LPG/CNG engines |
| Colmonoy | A cost-competitive hardfacing alternative to Stellite. | Strong abrasion resistance · economical | Standard-duty passenger & two/three-wheeler valve facing |
Seven industries, one valve range built for each of them.
Engine valves don't fail politely - they fail expensively, in the middle of a duty cycle the customer was counting on. That's why we build valves specific to the demands of each industry we serve, rather than a one-size-fits-all part.
Automotive
Passenger car and light commercial vehicle engine valves, manufactured to OEM tolerances for new-vehicle production and the aftermarket.
Commercial & Heavy Vehicles
Valves engineered for the higher thermal and mechanical loads of trucks, buses and off-highway diesel engines.
Two & Three-Wheelers
High-volume valve production for motorcycles, scooters and auto-rickshaws.
Agriculture & Tractors
Valves built for extended run-time under dust, heat and inconsistent maintenance schedules.
Marine [TBC]
Valves for marine propulsion and auxiliary engines, where corrosion resistance matters as much as durability.
Power Generation & Stationary Engines
Generator sets, compressors and industrial stationary engines that need to start reliably.
Industrial Equipment
Custom and reverse-engineered valves for industrial machinery outside standard automotive use cases.
Six process stages, one continuous quality chain.
Forging, machining, heat treatment, coating, grinding and inspection all happen under one roof in Rajkot - so tolerance control doesn't depend on a third-party subcontractor.
From bar stock to finished valve
Six process stages under one roof in Rajkot - so tolerance control never depends on a third-party subcontractor.
Hot Forging Line
Alloy steel bar stock heated and forged to near-net shape under controlled temperature.
CNC Turning & Profiling
Stem, head and seat geometry machined to drawing tolerance on CNC lines.
Hardening & Tempering
Controlled cycles set metallurgical properties for stem wear and seat durability.
Stellite / Induction Facing
Seat and tip facing applied where the application calls for extra wear or heat resistance.
Grinding & Plating
Precision grinding and hard-chrome stem plating bring parts to final dimension.
Dimensional Inspection
Every batch measured against the OEM drawing before packing.
Built to hold export lead times
[[NEEDS INPUT]] facility floor area / headcount / manufacturing-unit count not yet confirmed
How we hold tolerance, batch after batch
A valve that looks right on the outside can still fail on the inside if the material, heat treatment, or tolerance is off - so we control quality at every stage rather than relying on a final check to catch problems. Every export order ships with material test certificates and inspection reports. We do not hold a formal ISO or IATF certification at this time - this section intentionally doesn't claim one.
Incoming material verification
Every batch of raw steel is verified against grade and composition specification before it enters production.
In-process inspection
Dimensional checks at each machining stage - not just at the end of the line - catch deviations before they compound.
Heat treatment control
Hardness and thermal treatment are monitored and logged per batch.
Final inspection & testing
Finished valves are checked for dimensional accuracy and surface finish before packing.
Batch traceability
Every shipment can be traced back to its production batch and material certificate on request.
Packaging & dispatch check
Quantity, labeling and packing-list details are verified against the order before a shipment leaves the plant.
Exporting from Gujarat to five continents.
35+ active export markets across Africa, the Middle East, South & Southeast Asia, Latin America and Europe - served from a single manufacturing base in Rajkot.
Africa & Middle East Primary region
- Nigeria
- Kenya
- Tanzania
- Ghana
- UAE
- Saudi Arabia
- Iraq
- Oman
Asia & Beyond Growth region
- Bangladesh
- Nepal
- Sri Lanka
- Indonesia
- Vietnam
- Philippines
- Peru
- Colombia
What happens after you place an order
Quotation & sample
Share your part number, drawing or a sample - we confirm spec and send a quotation with lead time.
Production & inspection
Your order runs through our six-stage process with 100% dimensional inspection before packing.
Documentation & dispatch
Material certs and inspection reports are packaged with the shipment, ready for customs clearance.
Let's talk about your valve requirement.
Whether you need a quote on a standard catalog valve, a custom specification, or you're evaluating us as a new supplier, tell us a bit about what you need and we'll respond with a straight answer - not a generic brochure.
To Speed Up Your Quote, Please Include
- Vehicle/engine make, model and year (or OEM part number if known)
- Quantity required
- Destination country (for export shipments)
- Any specification documents, drawings or samples you can share
Send an Inquiry
Register your code.
Earn a point every time.
Every Antra valve box carries a reward card with a unique code. Enter it here - each valid code is worth 1 point.
- 1Find the card in the boxYour unique 8-character code is printed on it.
- 2Enter the code and your detailsCode, mobile, name, city and the product fitted.
- 31 point is creditedThe code closes so it can't be used twice. [[points per gift TBC]]
Register your purchase
All fields required.
Can't find your code?
It's printed on the Antra Power Rewards card inside the valve box - 8 characters, starting AN.
Card missing or unreadable?
Send a photo of the card and the box on WhatsApp and we'll sort it out.
Who can join?
Mechanics, retailers and distributors. Genuine Antra packs only, one registration per code. [[full terms TBC]]
Privacy Policy
This Privacy Policy explains how Antra Industries (trading as "Antra Auto Tech") collects, uses and protects information submitted through antraautotech.com.
What we collect
- Information you submit through our contact/inquiry form: name, company, email, phone/WhatsApp number, country, and message content.
- Antra Rewards registrations: your name, mobile number, city, the pack code you register, and the vehicle or engine model the part was fitted to.
- Standard technical data collected automatically by any website. [[NEEDS INPUT: confirm analytics tool, if any]]
How we use it
To respond to quote requests and business inquiries, and to maintain records of customer/distributor communication. Rewards registrations are used to verify the code, credit your rewards balance, and contact you about it. We do not sell or rent your information to third parties.
Cookies
[[NEEDS INPUT: confirm actual cookie usage once implemented]]
Data retention
[[NEEDS INPUT: confirm retention period]]
Your rights
You may request access to, correction of, or deletion of your personal data by contacting info@antraautotech.com.
Contact
Antra Industries, Plot No. G-2118, Kishan Gate No. 3, Metoda G.I.D.C., At Lodhika, Dist. Rajkot - 360021, Gujarat, India · info@antraautotech.com
Terms & Conditions
These terms govern use of antraautotech.com, operated by Antra Industries (trading as "Antra Auto Tech"). This website is an informational and inquiry channel - placing an inquiry through this site does not itself constitute a binding purchase order; actual sales terms are agreed separately per order.
Website use
Content on this site (product descriptions, material specifications, images) is provided for general reference. Material grade information should be confirmed against actual mill/supplier certificates for any specific order.
Quotations
Quotations provided in response to inquiries are subject to confirmation and are not binding until a formal order is accepted in writing. [[NEEDS INPUT: payment terms, MOQ policy, lead times, Incoterms]]
Intellectual property
Site content, the Antra Auto Tech name and logo are the property of Antra Industries. [[NEEDS INPUT: trademark registration status]]
Governing law
[[NEEDS INPUT: confirm governing jurisdiction]]
Disclaimer
Material & specification information
Material grades, chemical compositions, and technical specifications published on this site are typical industry reference values provided for general guidance only. They do not constitute a guarantee of the composition or performance of any specific batch or shipment.
Product images
Product and facility images on this site are illustrative placeholders and may not depict the exact part, finish, or facility configuration for every order.
No warranty implied
Nothing on this website constitutes a warranty of merchantability or fitness for a particular purpose beyond what is explicitly agreed in a written order confirmation.
Third-party links
This site may link to third-party sites (e.g. WhatsApp, Google Maps, social media). Antra Industries is not responsible for the content or privacy practices of those third-party sites.