Hot Distortion Tester is equipped with a gas burner mechanism, specimen clamping mechanism and sensing mechanism which are controlled by PLC and observed on screen touch HMI. By default it can measure distortion of a 1/4”x1”x4”) standard transverse specimen.

Product Name:	Hot Distortion Tester
Product Code:	VHD I
Order Reference Code:	V0000116
Electrical Supply Required:	230v 50Hz A.C. (Default) 110v 60 Hz A.C (Optional) Single Phase, Stabilized with Over/ Under Voltage cut-off.
Electrical Plug:	M type : 15 Amp Plug
Typical Maximum Current:	1.2 A at 230V
Compressed air Supply:	Not Required
Communication:	Ethernet (RJ45) CloudSync using V-Sync
Dimensions:	685x390x360 mm (WxBxH)
Packing Dimensions:	790x500x460 mm (WXBXH) Typical
Net Weight:	Approximately 40 kg
Gross Weight:	Approximately 50 kg
Colour:	Factory Default
Measuring Range:	Distortion: ±7mm
Traceable to:	NABL Standards
Least Count:	Distortion: 0.01 mm
Specimen Requirements:	Required
Operating Temperature:	0-500C
Testing Standards:	BIS/AFS
Calibration Frequency:	22500 nos. of Testing Cycles or Once in Year

• Hot Distortion Tester.
• Standard calibration plate.
• Calibration certificate.
• Instruction manual.

Sand Splitter : To get representative sample

Specimen preparation equipment’s to make a standard specimen.

Standard slip gauge: 7mm

NA

Hot Distortion Tester VHD

The Importance and Use of Hot Distortion Testing in Foundry Sands

In modern metal casting, achieving consistent quality and reducing rejections is a top priority. One often-overlooked but critical contributor to casting defects is thermal distortion in mould and core materials. The Hot Distortion Test plays a vital role in diagnosing and preventing such defects by evaluating how foundry sand systems behave when subjected to high temperatures.

 Why Hot Distortion Testing Matters

Chemically bonded moulds and cores, especially those exposed directly to molten metal, undergo extreme thermal stress during casting. If the sand system lacks thermal stability, the binder or sand matrix can distort, leading to a cascade of defects such as:

• Veining and Expansion Cracks: Resulting from uneven or excessive expansion.

• Metal Penetration: Caused by loss of sand strength and surface integrity.

• Scabbing and Buckling: Due to non-uniform distortion and binder degradation.

Hot distortion testing simulates these conditions under controlled parameters, providing foundries with quantitative data on how their sand formulations will perform in actual casting environments.

 How the Test Works

A standard sand specimen is subjected to a direct flame in the Hot Distortion Tester (VHD I). As the specimen heats, a non-contact sensor records its deformation over time, producing a distortion curve. The test concludes when the specimen fails due to thermal stress.

Key outcomes of the test include:

• Maximum distortion value (mm)

• Time to failure (s)

• Distortion curve shape, indicating binder resilience and structural integrity

These insights enable foundries to:

• Compare different sand-binder systems

• Optimize binder levels and curing parameters

• Qualify new suppliers or raw materials

• Monitor production batch-to-batch consistency

 Applications Across Foundry Operations

Application Area	Role of Hot Distortion Test
R&D & QA	Benchmark new sand formulations or resin systems
Process Optimization	Tune additive and binder levels for better thermal resistance
Supplier Evaluation	Validate sand quality before large-scale procurement
Defect Diagnosis	Correlate distortion behavior with observed casting defects

🏭 Real-World Value in Foundries

Foundries that integrate hot distortion testing into their quality control framework benefit from:

• Lower scrap and rework rates

• Improved casting dimensional accuracy

• Enhanced confidence in new tooling or mould design

• Faster troubleshooting and root cause analysis

By identifying how sands behave under heat before actual casting, foundries can make proactive adjustments—saving time, money, and resources.

VHD I: Designed for Precision and Simplicity

The Versatile Hot Distortion Tester (Model: VHD I) offers unmatched ease of use, accuracy, and digital traceability. Its touchscreen interface, automated flame control, and Industry 4.0 connectivity make it ideal for both production and R&D environments.

Predicting how chemically bonded molds and cores will behave when hit by molten metal is one of the most difficult challenges in the foundry. Conventional tests like grain fineness or tensile strength only tell part of the story; they measure properties at room temperature. To truly minimize casting defects like veining, cracking, or mold breakage, you need to understand sand behavior at elevated temperatures.

The Versatile Hot Distortion Tester (VHD) provides this insight by measuring the millimetric deflection of a cured sand specimen as it is preferentially heated on one side.

Understanding the Hot Distortion Curve (HDC)

A single test generates a comprehensive curve that describes four critical stages of sand performance:

• Region 1: Upward Deflection (Expansion) Driven by the base sand, this measures how much the sand expands when first exposed to heat. Minimizing this expansion is key to maintaining dimensional accuracy and reducing casting stress.

• Region 2: Thermoplastic Relaxation (Plasticity) As the binder begins to melt or decompose, the specimen "sags" or relaxes. Controlled plasticity is vital; it helps avoid hot cracking and veining by allowing the mold to "give" slightly under thermal shock.

• Region 3: Thermosetting This region marks the point where the chemical binder fully cures due to heat, transitioning from a plastic state back to a rigid, thermoset state.

• Region 4: Degradation and Failure Eventually, the binder burns out, leading to mechanical failure. The "time to failure" is an indicator of hot strength. While high hot strength prevents mold breakage, it can also lead to poor collapsibility during shakeout.

From Research Tool to Production Control

Historically, hot distortion testing was a qualitative research tool because the curves were too complex for manual calculation. Versatile has transformed this with a fully automated, digital system:

• Statistical Tolerance Bands: Our software automatically calculates ±3 sigma control limits based on your "normal" process.

• Real-Time Monitoring: Operators can see live production tests plotted against these tolerance bands on a color monitor. If the curve intersects a limit, the system visually depicts that the process has drifted out of control.

• Data Integration: All data can be exported to spreadsheets for detailed X-bar and R-charting, enabling deep process capability studies.

Why Choose the Versatile Hot Distortion Tester?

• Precision Sensing: Measures deflection with 0.01mm accuracy.

• Automated Operation: Single-touch operation with a fully automated burning mechanism ensures operator-to-operator consistency.

• Comprehensive Analysis: Store, retrieve, and compare multiple curves to evaluate new sand formulations or binder grades before they reach the production floor.