Custom Vacuum Furnace Water-Quench Fixtures for High Temperature Heat Treatment

Customer Case Study | Custom Design & Manufacturing for RTI, France
Customer: RTI, France
Product: Custom Vacuum Furnace Basket / Heat Treatment Fixture
Application: High-Temperature Vacuum Heat Treatment & Water Quenching
Maximum Furnace Temperature: 1200°C
Quench Water Temperature: 20–50°C
Maximum Furnace Load: 800 kg
Loading Zone: 1200 × 800 × 800 mm
Service: Engineering Design + Drawing + Manufacturing
Manufacturer: Wuxi Junteng Fanghu Alloy Technology Co., Ltd. (FH® Alloy)

Project Overview
FH® Alloy was commissioned by RTI, France to develop a customized vacuum furnace basket and heat treatment fixture system for a high-temperature vacuum furnace with a water-quenching process.

Unlike a standard build-to-print project, the customer provided the main furnace operating parameters, loading limits and available loading space, while FH® Alloy was responsible for designing the fixture structure, preparing the manufacturing drawings and producing the finished furnace tooling.

The operating conditions presented a demanding engineering challenge. The fixture would be exposed to furnace temperatures of up to 1200°C, followed by rapid water quenching at approximately 20–50°C. At the same time, the furnace had a maximum loading capacity of 800 kg and an available loading zone of 1200 × 800 × 800 mm.

The fixture therefore needed to combine high-temperature structural stability, load-bearing capability and resistance to severe thermal cycling.

Customer Requirements
RTI provided FH® Alloy with the key furnace and process parameters required for fixture development.

Based on these conditions, the fixture could not simply be designed according to external dimensions. Its structural layout also had to consider repeated heating, rapid cooling, load distribution and dimensional stability.

Engineering Challenge: From 1200°C to Water Quenching
One of the most important considerations in this project was the large temperature change between the heat treatment stage and water-quenching stage.

The fixture may operate at temperatures approaching 1200°C before entering quenching water at approximately 20–50°C.

This severe thermal cycle can create substantial thermal stress within the fixture structure.

The engineering design therefore needed to address:

• Thermal expansion at high temperature
• Thermal contraction during rapid cooling
• Thermal shock during water quenching
• Structural deformation after repeated cycles
• Load distribution under high-temperature conditions
• Water drainage during quenching
• Fixture stability during loading, heating, quenching and unloading

These conditions make water-quench furnace fixtures considerably more demanding than conventional furnace baskets used only for heating and air cooling.

Fixture Design Based on the Furnace Loading Zone
The available furnace loading space was:

1200 × 800 × 800 mm
FH® Alloy used this loading envelope as one of the principal design constraints when developing the fixture.

The engineering team needed to balance several factors:
Maximum Use of Furnace Space
The basket structure had to make effective use of the available furnace volume while maintaining adequate clearance for loading, unloading and furnace operation.

Structural Strength
The furnace permitted a maximum load of 800 kg.
The fixture design therefore needed sufficient structural strength while avoiding unnecessary self-weight that would reduce the available payload for the customer's workpieces.

Uniform Load Distribution
The supporting structure was designed to distribute the workpiece load as evenly as possible and reduce local stress concentration at elevated temperatures.

Thermal Expansion Allowance
At temperatures up to 1200°C, dimensional expansion becomes an important engineering consideration.
The design therefore needed to allow for thermal movement rather than excessively restricting the structure, helping reduce the risk of distortion during repeated heat treatment cycles.

Design Considerations for Water Quenching
Water-quenching fixtures require additional structural considerations that are not as critical for conventional heat treatment tooling.

Open Structure
An appropriate open-frame structure helps quenching water rapidly reach the workpieces and fixture surfaces.

Fast Water Drainage
The geometry should avoid unnecessary closed cavities or areas where water can remain trapped after quenching.

Reduced Thermal Stress Concentration
Section transitions, joints and supporting members need to be designed carefully to minimize localized stress during rapid temperature changes.

Structural Rigidity
The fixture must retain sufficient rigidity during loading and handling while also accommodating thermal expansion and contraction.
The final design therefore requires a balance between strength, weight, thermal movement and quenching efficiency.

From Customer Parameters to Manufacturing Drawings
One of the key features of this project was that RTI did not simply provide a finished production drawing for FH® Alloy to manufacture.
Instead, FH® Alloy provided an engineering-to-manufacturing service.

The project workflow included:
Furnace Parameters → Application Analysis → Structural Design → Drawing Preparation → Customer Review → Manufacturing → Inspection

1. Operating Condition Review
FH® Alloy reviewed the customer's:

• Furnace dimensions
• Maximum furnace temperature
• Water-quenching temperature
• Maximum load
• Loading space
• Heat treatment process requirements

2. Structural Concept Development
Based on the operating conditions, the fixture structure was developed with consideration for:

• Loading capacity
• High-temperature strength
• Thermal expansion
• Water-quenching behavior
• Handling requirements
• Dimensional limitations

3. Engineering Drawing Preparation
FH® Alloy prepared the fixture drawings according to the proposed structural design.
The drawings provided the basis for customer review and subsequent production.

4. Manufacturing
After the design was finalized, the fixture components were manufactured and assembled according to the approved drawings and technical requirements.

5. Final Inspection
Before delivery, key aspects of the finished fixture were inspected, including:

• Overall dimensions
• Structural geometry
• Assembly condition
• Critical connection areas
• Surface condition
• Conformance with approved drawings

Why Fixture Weight Matters in an 800 kg Furnace
The furnace has a specified maximum loading capacity of 800 kg.
For this reason, fixture design must consider not only whether the tooling itself is strong enough, but also the relationship between:

Fixture Weight + Workpiece Weight ≤ Furnace Maximum Load
An excessively heavy fixture reduces the amount of product that can be processed in each furnace cycle.
FH® Alloy therefore evaluates structural strength and fixture weight together during the design stage to achieve an appropriate balance between load capacity, durability and usable furnace payload.

Project Specifications

More Than Build-to-Print Manufacturing
For many furnace tooling projects, customers already have complete drawings and only require manufacturing.

This RTI project was different.

The customer supplied the operating conditions and furnace parameters, and FH® Alloy converted those requirements into a manufacturable furnace fixture solution.

This capability allows FH® Alloy to support customers who need more than OEM production, including projects requiring:

• Fixture concept development
• Structural optimization
• Material selection support
• Loading layout optimization
• Drawing preparation
• Custom manufacturing

Custom Vacuum Furnace Fixtures by FH® Alloy
Wuxi Junteng Fanghu Alloy Technology Co., Ltd. (FH® Alloy) designs and manufactures customized heat treatment tooling for industrial furnaces, including:

• Vacuum Furnace Fixtures
• Water-Quench Furnace Baskets
• Heat Treatment Baskets
• Furnace Trays
• Heat Treatment Frames
• Stacking Fixtures
• High-Temperature Furnace Supports
• Custom Heat-Resistant Alloy Components

Fixtures can be developed according to customer drawings or designed based on parameters such as:
Furnace Type + Working Temperature + Loading Size + Maximum Load + Cooling Method + Workpiece Geometry

Need a Custom Fixture for Your Vacuum Furnace?
If you do not have a finished fixture drawing, FH® Alloy can develop the tooling based on your furnace and process information.

For engineering evaluation, customers can provide:

• Furnace type
• Maximum operating temperature
• Heating atmosphere
• Cooling or quenching method
• Loading zone dimensions
• Maximum furnace load
• Workpiece dimensions
• Workpiece weight
• Loading quantity
• Existing fixture drawings or photos, if available

FH® Alloy can support the complete process from fixture design and drawing preparation to manufacturing and inspection.

About FH® Alloy
Wuxi Junteng Fanghu Alloy Technology Co., Ltd. (FH® Alloy) specializes in customized high-temperature alloy components and furnace tooling for industrial heat treatment applications.
Our manufacturing capabilities cover heat treatment fixtures, furnace baskets, radiant tubes, furnace rollers, centrifugal cast tubes and other custom heat-resistant alloy components.

Custom Design | Custom Material | Custom Size | OEM Manufacturing