Graigar KT320 Digital Ultrasonic Metal Thickness Gauge User Manual

1. Introduction

The Graigar KT320 Digital Ultrasonic Metal Thickness Gauge is a precision instrument designed for accurate measurement of material thickness using ultrasonic principles. It is suitable for a wide range of materials that are good conductors of ultrasonic waves, including various metals (steel, cast iron, aluminum, copper), plastics, ceramics, glass, and fiberglass.

This device features advanced functionalities such as probe zero calibration, two-point calibration for system error correction, and the ability to measure sound velocity to enhance measurement accuracy. It includes a clear LED backlight display for use in low-light conditions, coupling status alerts, and battery level indication. The KT320 is designed for portability, high reliability, and resistance to vibration, impact, and electromagnetic interference, making it suitable for diverse operating environments. It also supports data processing, PC communication, and printing.

2. Safety Information

Please read and understand all safety instructions before operating the Graigar KT320 thickness gauge. Failure to follow these instructions may result in injury or damage to the device.

• Battery Safety: Use only the specified battery type (2x 1.5V AA). Do not mix old and new batteries or different types of batteries. Dispose of used batteries according to local regulations.
• Environmental Conditions: Operate the device within the specified temperature range (-10°C to 60°C). Avoid exposing the device to extreme temperatures, humidity, or corrosive environments.
• Handling: Handle the device with care. Avoid dropping or subjecting it to severe impacts.
• Coupling Agent: Use the provided or recommended coupling agent. Avoid contact with eyes and skin. In case of contact, rinse thoroughly with water.
• Maintenance: Do not attempt to open or repair the device yourself. Refer all servicing to qualified personnel.
• Probe Care: Ensure the probe surface is clean and free from damage before and after use to ensure accurate readings.

3. Package Contents

Upon unpacking, please verify that all items listed below are present and in good condition:

• Graigar KT320 Host Unit
• 5MHz Probe
• 4 mm Steel Calibration Block
• Coupling Agent (bottle)
• Instruction Manual
• USB Communication Cable (if included in specific package)
• Software CD (if included in specific package)
• Carrying Case (if included in specific package)

Image 3.1: Contents of the Graigar KT320 package, including the main unit, probe, calibration block, coupling agent, manual, and cables.

4. Product Overview

4.1 Front Panel and Display

Image 4.1: Front view of the KT320 gauge, showing the LCD display and control buttons.

The front panel features a clear LCD display and a set of control buttons for operation. The display shows measurement readings, unit indicators, battery status, and menu options.

Image 4.2: Close-up of the LCD display, showing measurement values and menu indicators.

4.2 Control Buttons

• Power Button (⏻): Turns the device ON/OFF.
• Save Button (💾): Saves current measurement data.
• Up Arrow (▲): Navigates up in menus or increases values.
• Down Arrow (▼): Navigates down in menus or decreases values.
• Backlight Button (☀): Toggles the LCD backlight.
• Calibration Button (⚙): Accesses calibration settings.
• Enter/Back Button (↵): Confirms selection or returns to the previous screen.
• Sound/Alarm Button (🔊): Controls sound or alarm functions.
• Unit/Balance Button (⚖): Toggles measurement units (Metric/Imperial) or other balance functions.

4.3 Rear Panel

Image 4.3: Rear view of the KT320 gauge, showing the battery compartment and product label.

The rear panel houses the battery compartment, which requires two 1.5V AA batteries for operation. The product label with model and power information is also located here.

5. Setup

5.1 Battery Installation

1. Locate the battery compartment cover on the rear of the device.
2. Slide the cover downwards or unclip it to open the compartment.
3. Insert two 1.5V AA batteries, ensuring correct polarity (+/-) as indicated inside the compartment.
4. Replace the battery compartment cover, ensuring it clicks securely into place.

5.2 Probe Connection

Connect the probe cable to the designated port on the top or side of the KT320 unit. Ensure the connection is firm to prevent signal loss during measurements.

5.3 Powering On

Press and hold the Power Button (⏻) for a few seconds until the LCD display illuminates. The device will perform a self-test and display the initial measurement screen.

6. Operating Instructions

6.1 Probe Zero Calibration

Probe zero calibration compensates for any delay in the probe and cable. This should be performed before initial use or if the probe is changed.

1. Ensure the probe is clean and free of coupling agent.
2. Press the Calibration Button (⚙) to enter the calibration menu.
3. Select "Zero Calibration" (or similar option) using the arrow buttons and confirm with the Enter Button (↵).
4. Follow on-screen prompts to complete the calibration.

6.2 Two-Point Calibration

Two-point calibration improves accuracy over a specific measurement range by using two known thickness values.

1. Apply coupling agent to the 4mm steel calibration block.
2. Place the probe firmly on the 4mm block and take a reading.
3. Enter the calibration menu and select "Two-Point Calibration."
4. Input the known thickness (4.00mm) for the first point.
5. Repeat the process with a second known thickness standard (if available and required for your application).
6. Confirm the calibration.

6.3 Taking Measurements

1. Prepare the Surface: Ensure the surface of the material to be measured is clean, smooth, and free of rust, paint, or debris.
2. Apply Coupling Agent: Apply a small amount of coupling agent to the measurement area on the material. This eliminates air gaps between the probe and the material, which would block ultrasonic waves.
3. Place the Probe: Press the probe firmly and flatly against the prepared surface.
4. Read the Display: The thickness reading will appear on the LCD display. If the coupling is poor, the display may show an error or an unstable reading. Adjust the probe position or reapply coupling agent.
5. Remove Probe: Lift the probe from the surface. The last stable reading will typically remain on the display.

6.4 Sound Velocity Measurement

If the sound velocity of a material is unknown, but its thickness is known, the KT320 can measure the sound velocity.

1. Enter the sound velocity measurement mode via the menu.
2. Input the known thickness of the material.
3. Apply coupling agent and place the probe on the material.
4. The device will calculate and display the sound velocity.

6.5 Data Memory and PC Communication

The KT320 can store up to 5 files, with each file holding up to 100 measurement values. It also stores 5 sound velocity values. Use the Save Button (💾) to store readings. For PC communication and printing support, connect the device to a computer using the appropriate USB cable and software (if provided).

6.6 Unit Selection

Press the Unit/Balance Button (⚖) to toggle between Metric (mm) and Imperial (inch) units as desired.

7. Maintenance

7.1 Cleaning

• After each use, wipe the probe surface and the main unit with a soft, dry cloth to remove any coupling agent residue or dirt.
• Do not use abrasive cleaners or solvents, as these can damage the device.

7.2 Battery Replacement

When the battery indicator shows low power, replace the batteries promptly to ensure accurate operation. Refer to Section 5.1 for battery installation instructions.

7.3 Storage

When not in use for an extended period, remove the batteries to prevent leakage. Store the device and its accessories in the provided carrying case in a cool, dry place, away from direct sunlight and extreme temperatures.

8. Troubleshooting

9. Specifications

10. Warranty and Support

For warranty information, technical support, or service inquiries, please refer to the documentation included with your purchase or contact Graigar customer service directly. Keep your purchase receipt as proof of purchase for warranty claims.