--- title: "Neutral Hardening" url: "https://uptonindustries.com/application/neutral-hardening/" description: "Upton ceramic, high-speed, internally heated and externally heated salt bath furnaces plus automated systems for neutral hardening." site: "Upton Industries" updated: "2026-09-25T04:24:43+00:00" breadcrumbs: "Home > Applications > Neutral Hardening" --- # Neutral Hardening Upton ceramic, high-speed, internally heated and externally heated salt bath furnaces plus automated systems for neutral hardening. 5 Upton systems · Salt Bath - **Process:** Neutral Hardening - **Equipment type:** [Salt bath furnaces](https://uptonindustries.com/application/neutral-hardening/#route-salt) - **Systems:** 5 [Request a quote for a neutral hardening system](https://uptonindustries.com/contact/?need=equipment&equipment=salt-bath&ref=Neutral%20Hardening) ## Plan your equipment Neutral hardening can run in a salt bath furnace, a heated salt pot or an automated line. Send the material, part dimensions, load and required cycle, and we’ll talk through which fits. ## Salt bath furnaces ### [Automated Salt Bath Systems](https://uptonindustries.com/products/salt-bath-furnaces/automated/) Upton configures automated salt bath systems with PLC controls and material handling for multiple processes. ### [Ceramic Salt Bath Furnaces](https://uptonindustries.com/products/salt-bath-furnaces/ceramic/) U-ABCD Only the faces of Upton’s submerged electrodes touch the salt, so the electrodes take up none of the bath space. ### [Externally Heated Salt Pot Furnaces](https://uptonindustries.com/products/salt-bath-furnaces/externally-heated/) Externally heated salt pot furnaces with carbon-steel or stainless-steel liners, electric resistance heaters or Upton Hurricane gas burners, for intermittent service. ### [High Speed Salt Bath Furnaces](https://uptonindustries.com/products/salt-bath-furnaces/high-speed/) U-HS For high-speed and tool steel heat treating. A film of salt on each part slows cooling on the way to the quench. ### [Internally Heated Salt Bath Furnaces](https://uptonindustries.com/products/salt-bath-furnaces/internally-heated/) Internally heated salt bath furnaces for non-chloride salts, with carbon-steel or stainless-steel liners. ## Externally or internally heated Link: https://uptonindustries.com/application/neutral-hardening/#compare-salt-heating Both are steel-lined salt bath furnaces. They differ in where the heat enters the salt: through the wall of a pot, or directly in the bath. *Fig. 1 Where the heat enters the salt. Section views, not to scale.* *Externally Heated Salt Pot Furnaces & Internally Heated Salt Bath Furnaces compared* | | [Externally Heated Salt Pot Furnaces](https://uptonindustries.com/products/salt-bath-furnaces/externally-heated/) | [Internally Heated Salt Bath Furnaces](https://uptonindustries.com/products/salt-bath-furnaces/internally-heated/) | | --- | --- | --- | | Heat enters | From outside the pot, through its wall | In the salt, from heat sources immersed in the bath | | Electric | Electric resistance heaters | Immersion heaters for lower-temperature work; air- or water-cooled electrodes with transformers at elevated temperatures | | Gas | Upton Hurricane tangential burners, designed to minimize flame impingement on the salt pot | Radiant tubes | | Suited to | Intermittent service | Non-chloride salt applications | | Liner | Carbon steel or stainless steel, selected for the operating conditions | Carbon steel or stainless steel, selected for the operating conditions | | Drawings (PDF) | [Round: Upton Externally Heated Salt Pot Furnace (Round)](https://uptonindustries.com/wp-content/uploads/2018/04/externally-heated-salt-pot-furnace-round.pdf); [Square: Upton Externally Heated Salt Pot Furnace (Square)](https://uptonindustries.com/wp-content/uploads/2018/04/externally-heated-salt-pot-furnace-square.pdf) | [Electrodes: Internally Heated Salt Bath Furnaces (Electrodes)](https://uptonindustries.com/wp-content/uploads/2018/04/upton-internally-heated-salt-bath-furnace.pdf); [Heaters: Internally Heated Salt Bath Furnaces (Heaters)](https://uptonindustries.com/wp-content/uploads/2018/04/upton-internally-heated-salt-bath-furnace-heaters.pdf) | To quote either furnace, send us: - Part sizes - Load weight - Process temperature - The salt you plan to run ## Related processes - [Austempering 4 shared systems](https://uptonindustries.com/application/austempering/) - [Marquenching 4 shared systems](https://uptonindustries.com/application/marquenching/) - [Martempering 4 shared systems](https://uptonindustries.com/application/martempering/) - [Degreasing 3 shared systems](https://uptonindustries.com/application/degreasing/) - [Descaling 3 shared systems](https://uptonindustries.com/application/descaling/) - [Drawing 3 shared systems](https://uptonindustries.com/application/drawing/) ## Need a custom thermal solution? Send us your process details to start a quote. [Request a quote](https://uptonindustries.com/contact/?need=equipment&equipment=salt-bath&ref=Neutral%20Hardening)