Vacuum Carburizing Furnace · Overview
Clean Case Hardening Without Intergranular Oxidation
Lakshmi Vacuum Technologies builds vacuum carburizing furnaces that diffuse carbon into gears, shafts and transmission parts under vacuum — then quench them in high-pressure inert gas up to 20 bar. No oxygen in the chamber means no intergranular oxidation, so the surface stays clean and the grinding allowance shrinks.
Low-pressure carburizing replaces the pit furnace with short acetylene boost pulses and controlled diffusion. Case depth is built pulse by pulse and logged by PLC and IPC with SCADA, so the same recipe gives the same case, load after load — with far less distortion than atmosphere carburizing.
Every furnace is engineered to order at our Bengaluru works: working area, hot zone, number of zones, quench pressure and process gas are configured around your parts and your case-depth specification.
Working Area up to 900 × 900 × 1200 mm
Process
How Low-Pressure Carburizing Works
Boost & Diffuse
Acetylene is pulsed into the hot vacuum chamber, then pumped away so carbon diffuses into the surface. The cycle repeats until the required case depth is built up.
Control the Case
PLC and SCADA hold temperature, gas flow and pulse timing recipe by recipe, so case depth and surface carbon stay repeatable from load to load.
Quench & Unload
High-pressure nitrogen or argon at 10–20 bar (or oil, where specified) locks in a hard case over a tough core. Parts unload clean, with no intergranular oxidation to grind away.
Technical Specifications
Built to Your Case Depth, Sized to Your Load
Working area, hot zone, quench pressure and process gas are all customised to your parts. Send your component drawings for a configured quotation.
Applications
Where This Furnace Earns Its Keep
Gearbox & Transmission Parts
Deep, uniform case hardness with a tough core for automotive and industrial gearboxes.
Shafts & Bearing Components
Wear-resistant surfaces on high-load power transmission parts, with controlled distortion.
Large Components
Heavy parts that need consistent case depth across the section without intergranular oxidation.
Aerospace Flight Parts
Surface-hardened flight hardware processed with documented metallurgical control.
Tooling & Dies
Case hardening of tooling where dimensional stability matters as much as surface hardness.
High-Volume Production
Repeatable processing of transmission and engine components, load after load.
Why Vacuum Carburizing
The Case for Carburizing Under Vacuum
No Intergranular Oxidation
Vacuum carburizing eliminates the IGO that atmosphere furnaces leave behind, improving fatigue life and cutting the grinding allowance.
Even Carbon Diffusion
Gas pulses under vacuum diffuse carbon uniformly, so case depth and surface hardness are controlled, not guessed.
Recipe-Level Repeatability
PLC, IPC and SCADA log every boost, diffuse and quench step, so the same recipe gives the same result.
Quench Tailored to the Part
10–20 bar gas quenching (or oil) is selected per part family to hit core hardness with minimum distortion.
FAQs
Frequently Asked Questions
What is low-pressure carburizing (LPC)?
LPC introduces hydrocarbon gas such as acetylene into a vacuum furnace in short boost pulses, lets the carbon diffuse into the steel surface, and repeats until the target case depth is reached. Because the atmosphere holds no oxygen, the surface stays free of intergranular oxidation.
Why is LPC better than traditional gas carburizing?
Traditional atmosphere carburizing exposes parts to oxygen and water vapour, which grow intergranular oxides and force a grinding allowance. LPC runs under vacuum, so IGO is eliminated, distortion is lower and case depth is controlled by gas pulses rather than by time in a pit.
Which materials can be carburized in your furnaces?
Case-hardening and low-alloy steels such as 16MnCr5, 20MnCr5, 8620, 9310 and equivalent Indian grades, plus tool steels and bearing steels. The exact cycle is set from your material, required case depth and core hardness.
What quenching is available after carburizing?
High-pressure inert-gas quenching at 10, 12, 15 or 20 bar with nitrogen or argon, and oil quench where the section and distortion limits call for it. Quench pressure is selected per part family and recorded in the recipe.
Can case depth and hardness be tightly controlled?
Yes. PLC and IPC with SCADA log every boost, diffuse and quench step, so case depth, surface carbon and hardness repeat from load to load. Coupons and metallographic checks verify the result before release.
Which industries use vacuum carburizing?
Automotive gearboxes and transmission components, off-highway and agricultural drivetrains, aerospace flight parts, bearing and tooling manufacturers, and general precision engineering where wear resistance with a tough core matters.
Still have questions? Talk to our engineers or request a quotation.
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