1.4848 Carburizing Furnace Heat Treatment Toolings & Fixtures for Ipsen 1.2-ton TQ13 Furnaces, Oil-Cooled at 980°C

Carburizing furnace Heat Treatment Fixtures & Toolings

Carburizing furnace fixtures are specialized support and fixturing systems used in processes such as gas carburizing and carbonitriding. Their core objective is to ensure the active atmosphere uniformly surrounds each workpiece to achieve consistent case depth and carbon concentration during the prolonged high-temperature (typically 900-950°C) carburizing cycle, often lasting tens of hours, while maximizing the loading rate and effectively controlling workpiece distortion.

These fixtures combine the strength requirements of multi-purpose furnace fixtures with the atmosphere flow requirements of nitriding furnace fixtures, making them among the most heavily loaded and critically demanding fixtures in operation.

I. Main Types and Structural Forms
Carburizing furnace fixtures are typically heavy-duty, modular systems, particularly used in pit furnaces, box-type/multi-purpose furnaces, and pusher-type continuous carburizing furnaces.

1. Pit-Type Carburizing Furnace Fixture System:

• Structure: Core system consists of a base, retort (furnace pot), and hanging fixtures (baskets/racks).
• Baskets/Racks: Hung in the center of the retort, usually cylindrical or polygonal frames welded from heat-resistant steel bars/plates, with internal tiered plates. Workpieces are stacked or hung inside.
• Design Key Points: Must ensure unobstructed atmosphere circulation channels from the retort wall to the basket center. A central flow guide (duct/cone) is often designed within the basket to force atmosphere, driven by a top fan, to flow downward through the workpieces and then return via the central duct, creating forced convection.

2. Box-Type / Multi-Purpose Furnace Carburizing Fixtures:

• Structure: Highly consistent with the multi-purpose furnace fixture system described earlier, but with higher material requirements. Composed of heavy-duty trays, high-strength stands, and baskets/spacers.
• Characteristics: Must withstand automatic transfer from the heating chamber to the quench chamber, placing extremely stringent demands on the flatness and strength of the trays.

3. Pusher-Type Continuous Carburizing Furnace Fixtures:

01. Structure: The heavy-duty tray (often called a "boat") is the core. It is progressively pushed on rails through multiple zones: preheat, carburize, diffuse, quench, etc.

02. Design Core:

• Tray/Rail Friction Pair: A major technical challenge. Requires using high-grade heat-resistant alloys (e.g., RA330) and optimized design (e.g., adding slide blocks, using dissimilar material pairs) to reduce friction and wear at high temperatures.
• Atmosphere Sealing: The gap between the tray and furnace hearth must be minimal yet not cause jamming, to prevent atmosphere mixing between zones.

II. Material Selection: The Decisive Factor for Lifespan
Failure of carburizing fixtures almost always stems from material embrittlement due to deep carburization and thermal fatigue cracking. Material selection is paramount.

01. Gold Standard Materials: High-Nickel-Chromium Austenitic Heat-Resistant Alloys. Their high nickel content effectively impedes the diffusion of carbon atoms, significantly slowing down the carburization rate of the fixture itself.

• Primary Choice: RA 330 (35Ni-18Cr) or equivalent. Offers the best overall combination of high-temperature strength, carburization resistance, and thermal fatigue resistance. It is the industry standard for heavy-duty carburizing fixtures.
• Common Choice: AISI 314 (25Cr-20Ni), AISI 310S. Slightly lower performance but more cost-effective, suitable for less demanding applications.
• Premium Choice: Inconel 600/601. Exceptional performance, with极强的 carburization resistance, but very expensive. Used for the most critical parts or where ultra-long service life is required.

02. Materials Strictly Prohibited: Plain carbon steels, low-alloy steels (e.g., AISI 1018, 4140). They will embrittle, expand, and crack due to severe carburization within just a few cycles, failing rapidly and generating large amounts of scale that contaminates the furnace and workpieces.

III. Summary
Carburizing furnace fixtures are the "backbone" of the carburizing process. They must remain stable under the harshest chemical environment (strong carburizing atmosphere) and the most severe physical conditions (high temperature, heavy load, long duration). The quality of their design and material selection directly determines:

• Case Uniformity and Consistency (Product Quality)
• Load per Batch and Production Efficiency (Production Cost)
• Fixture Lifespan and Maintenance Frequency (Equipment Cost)

A deep understanding of the principle that "carburization-resistant materials (e.g., RA330) are the foundation, and forced atmosphere flow design is the key" is central to successful carburizing fixture design and management. They are not merely racks for holding parts but are the directors of process gas flow and the invisible guardians of product quality.

Material Grade Table:

FAQ:

Q: How to give inquiry ?

A: Step 1, please give us some details about your furnace,operating temperature,cooling method,loading weight of your furnace and so on;

Step 2, it's better to provide 3D drawings;

Step 3, when we have enough details, we may design the products drawings and quote accordingly;

Q: When can I get the price?

A: We usually quote within 24 hours after we get your inquiry(Except weekend and holidays). If you are very urgent to get the price, please email us or contact us in other ways so that we can offer you a quote.

Q: When will make delivery ? /What is the delivery Time?

A: -Sample Order: 35 days after receipt of the full payment.

-Stock Order: 10 days after receipt of the full payment

-OEM Order: 30 days after receipt of the deposit.

Q: What's your after-sales service?

A: 1 year warranty for all kinds of products;

If you find any defective accessories first time, we will give you the new parts for free to replace in the next order, as an experienced manufacturer, you can rest assured of the quality and after-sales service.

Q: What's your payment condition?

A: T/T

Payment<=USD10000, 100% in advance. Payment>USD10000, 50% T/T in advance ,balance before shipment.

Q: What is the shipping method?

A: Transported by DHL, UPS, EMS, Fedex,Air freight, sea freight or train freight.