How to Measure Pipe Wall Thickness Using Benetech GM100 Plus and GM130 Malaysia

How to Measure Pipe Wall Thickness Using Benetech GM100 Plus and GM130 Malaysia

Introduction

Pipe wall thickness measurement is an important inspection activity in manufacturing factories, industrial maintenance facilities, water treatment plants and engineering operations throughout Malaysia.

Metal pipelines are commonly used to transport water, compressed air, chemicals and industrial process fluids. Over time, pipe walls may experience corrosion, erosion, mechanical wear and material thinning.

Regular inspection helps maintenance teams monitor the remaining wall thickness and identify areas that may require further engineering assessment.

The Benetech GM100 Plus and Benetech GM130 Ultrasonic Thickness Gauges are portable instruments designed for measuring the thickness of suitable materials using ultrasonic technology.

These instruments can perform measurements from one accessible side of a pipe when appropriate ultrasonic coupling and reflection conditions are available.

This guide explains how to measure pipe wall thickness using an ultrasonic thickness gauge, including preparation, calibration, probe selection, inspection techniques and troubleshooting.

1. Why Is Pipe Wall Thickness Measurement Important?

Industrial pipelines may gradually lose wall thickness because of operating conditions and environmental exposure.

Common causes include:

Internal Corrosion

External Corrosion

Erosion from Flowing Materials

Chemical Exposure

Moisture and Condensation

Mechanical Wear

Long-Term Equipment Operation

Excessive wall thinning may affect the structural integrity of a pipeline.

Benefits of Regular Pipe Thickness Inspection

Early Identification of Wall Thinning

Repeated measurements may reveal areas where material thickness has decreased.

Preventive Maintenance Planning

Inspection records help maintenance teams plan further assessments, repairs or replacements.

Improved Equipment Monitoring

Thickness readings provide useful information about the condition of selected pipe sections.

Reduced Need for Dismantling

Ultrasonic thickness measurement can often be performed without cutting or removing suitable installed piping.

Better Inspection Documentation

Recorded measurements allow technicians to compare readings collected at different inspection dates.

However, wall thickness measurement alone does not establish whether a pipeline is safe for continued operation. Engineering decisions must consider the applicable design requirements, operating conditions and inspection standards.

2. What Is an Ultrasonic Thickness Gauge?

An ultrasonic thickness gauge is a non-destructive testing instrument that measures material thickness using high-frequency sound waves.

The probe transmits ultrasonic energy into the material.

When the sound wave reaches a suitable reflecting boundary, part of the energy returns to the probe.

The instrument calculates thickness using the measured travel time and the configured sound velocity.

Basic Measurement Formula

Thickness = Sound Velocity × Echo Travel Time / 2

For example, when measuring a steel pipe, the operator must use a suitable sound velocity setting for the steel material.

If the sound velocity is incorrect, the displayed thickness may also be incorrect.

Why Ultrasonic Measurement Is Useful

Traditional measuring tools such as vernier calipers normally require access to the relevant measurement surfaces.

An ultrasonic thickness gauge can measure suitable pipe wall thickness from the outside without requiring access to the internal pipe surface.

This makes ultrasonic measurement useful for installed industrial pipelines.

3. Benetech GM100 Plus and GM130 Specifications

Both models are suitable for general ultrasonic thickness measurement, but they offer different functions.

SpecificationGM100 PlusGM130Measuring Range on Steel1.2–300 mm1.0–300 mmWorking Frequency5 MHz5 MHzSound Velocity Range1000–9999 m/s1000–9999 m/sAutomatic CalibrationYesYesLinear Automatic CompensationYesNoThickness Value StorageYesYesCoupling Status IndicationYesYesThickness AlarmNoYesMetric / Imperial ConversionNoYesMeasurement Mode SelectionNoYes6 mm Probe SupportNoYes10 mm Probe SupportYesYes

Important: The specified measurement ranges are based on the manufacturer's steel reference conditions. Actual performance depends on the selected probe, pipe diameter, material, surface condition and measurement technique.

GM100 Plus

The Benetech GM100 Plus is suitable for routine thickness measurement of steel plates, suitable pipes and industrial metal components.

GM130

The Benetech GM130 provides additional functions such as thickness alarm settings, measurement mode selection and support for compatible 6 mm and 10 mm probes.

The GM130 may be preferable when customers require these additional inspection features.

4. Equipment Required for Pipe Wall Thickness Measurement

Before starting an inspection, prepare the necessary equipment.

Ultrasonic Thickness Gauge

Use a suitable instrument such as the Benetech GM100 Plus or Benetech GM130.

Ultrasonic Probe

Select a compatible probe according to the instrument, pipe geometry and measurement requirements.

Ultrasonic Coupling Gel

Coupling gel helps transmit ultrasonic energy between the probe and pipe surface.

Calibration Reference

Use an appropriate reference sample or calibration block according to the manufacturer's instructions.

Surface Cleaning Tools

Prepare suitable cleaning materials to remove loose rust, dirt and contaminants.

Inspection Record

Record the pipe location, material, measurement date and thickness readings.

For critical inspection work, follow the relevant site procedures and applicable NDT requirements.

5. Step-by-Step Guide to Measuring Pipe Wall Thickness

Step 1 - Identify the Pipe Material

Determine the type of material being inspected.

Common materials include:

Carbon steel

Stainless steel

Aluminium

Other compatible metals

Different materials have different ultrasonic sound velocities.

Correct material identification is essential for reliable thickness measurement.

Step 2 - Inspect the Pipe Surface

Check the measurement area for:

Rust

Paint

Surface scale

Dirt

Uneven surfaces

Visible corrosion

Mechanical damage

Surface conditions may affect ultrasonic coupling and measurement accuracy.

Step 3 - Prepare the Measurement Area

Clean the selected pipe surface.

Remove loose contamination and prepare a suitable contact area for the ultrasonic probe.

If coating removal is required, obtain the necessary site approval and follow the applicable procedure.

Step 4 - Check the Instrument

Switch on the Benetech Ultrasonic Thickness Gauge.

Check the battery condition, probe connection and display operation.

Verify the instrument using the manufacturer's recommended procedure.

Step 5 - Set the Sound Velocity

Configure the appropriate sound velocity for the pipe material.

Where necessary, use a suitable known-thickness reference made from the same or a representative material.

Incorrect sound velocity settings can cause incorrect thickness readings.

Step 6 - Apply Coupling Gel

Apply a small amount of suitable ultrasonic coupling gel to the measurement location.

The coupling agent helps eliminate air gaps between the probe and the pipe surface.

Step 7 - Position the Probe

Place the ultrasonic probe firmly against the pipe surface.

Maintain stable contact and ensure that the probe orientation is appropriate for the pipe curvature.

Step 8 - Observe the Thickness Reading

Check the coupling indication and displayed thickness value.

If the reading is unstable, repeat the measurement after checking the surface and probe contact.

Step 9 - Repeat Measurements

Take repeated readings according to the inspection procedure.

For corrosion monitoring, measurements at multiple defined locations may be necessary.

Step 10 - Record the Results

Record:

Pipe identification

Measurement location

Pipe material

Instrument model

Probe used

Measurement date

Thickness readings

Relevant surface conditions

Consistent documentation is important for long-term pipe corrosion monitoring.

6. Example of Pipe Wall Thickness Inspection

Consider a hypothetical industrial steel pipeline undergoing periodic maintenance inspection.

The maintenance team records thickness measurements at several inspection locations.

Inspection PointMeasured ThicknessPoint A6.2 mmPoint B5.9 mmPoint C5.5 mmPoint D4.8 mmPoint E5.7 mm

These values are illustrative and do not represent actual inspection results.

Point D has the lowest recorded thickness.

This may justify additional measurements or engineering assessment.

However, the lowest reading does not automatically indicate that the pipe is unsafe.

Important Engineering Consideration

The acceptable remaining thickness depends on factors such as:

Pipe material

Original wall thickness

Operating pressure

Operating temperature

Pipe diameter

Corrosion allowance

Applicable design code

Inspection requirements

A qualified engineer should establish the minimum allowable wall thickness for critical applications.

7. How to Use GM130 Thickness Alarm Settings

The Benetech GM130 includes upper and lower thickness alarm settings.

This feature can help technicians identify measurements outside predefined screening limits.

Example

Suppose an engineer establishes a lower inspection screening threshold of 4.5 mm for a particular component.

The operator configures the GM130 according to that threshold.

If a measurement falls below the configured limit, the instrument can provide an alarm indication.

Advantages of Thickness Alarm Settings

Faster Screening of Multiple Measurement Points

Convenient Identification of Out-of-Range Readings

Improved Consistency During Routine Inspection

Support for Maintenance Documentation

Important: The alarm setting is a screening aid, not an automatic engineering safety decision.

The threshold must be established according to the relevant inspection requirements.

8. Which Probe Is Better for Pipe Thickness Measurement?

Probe selection is important when measuring curved pipe surfaces.

The GM100 Plus supports a 10 mm probe, while the GM130 supports compatible 6 mm and 10 mm probe options.

10 mm Probe

A 10 mm probe may be suitable for:

Flat steel plates

Large accessible surfaces

Suitable large-diameter pipes

General industrial components

6 mm Probe

A compatible 6 mm probe may be useful for:

Smaller measurement areas

Certain restricted locations

Some curved components

Applications requiring a smaller contact footprint

However, a smaller probe does not automatically guarantee accurate measurements on every small-diameter pipe.

Probe frequency, contact geometry, surface curvature and minimum measurable thickness must be considered.

Practical Recommendation

For routine measurements on suitable large metal surfaces, the GM100 Plus may be sufficient.

For applications requiring additional probe flexibility, consider the GM130.

9. Can Ultrasonic Thickness Gauges Measure Corroded Pipes?

Yes. Ultrasonic thickness gauges can support corrosion monitoring by measuring remaining wall thickness at suitable locations.

However, heavily corroded surfaces can create measurement difficulties.

Common Corrosion Measurement Challenges

Rough External Surfaces

Surface irregularities may reduce probe contact quality.

Internal Pitting

Localized internal corrosion may not be reliably characterized by a limited number of thickness readings.

Uneven Wall Thickness

Different measurement locations may produce different readings.

Poor Ultrasonic Reflection

Irregular internal surfaces can affect the returning ultrasonic signal.

Recommended Approach

Prepare the measurement surface appropriately.

Verify the instrument and probe.

Use a documented inspection procedure.

Record multiple readings where required.

Investigate unexpected thickness changes.

Use specialized NDT methods when necessary.

Neither GM100 Plus nor GM130 should be assumed to detect every localized corrosion defect.

10. Can GM100 Plus and GM130 Measure Through Paint?

This is a common question for industrial maintenance technicians.

Many installed steel pipelines are covered with protective paint or coatings.

Standard ultrasonic thickness measurements may be affected by the coating layer.

The Benetech GM100 Plus and GM130 should not be assumed to provide specialized through-coating thickness measurement.

For applications where paint cannot be removed, customers may need an instrument specifically designed to measure substrate thickness through coatings.

The measurement method should be confirmed before purchasing an ultrasonic thickness gauge.

11. Common Pipe Thickness Measurement Problems

Problem 1 - No Thickness Reading

Possible causes:

Insufficient coupling gel

Poor probe contact

Incorrect settings

Unsuitable surface condition

Probe connection problems

Solution: Check the probe connection, prepare the surface and verify the instrument settings.

Problem 2 - Unstable Reading

Possible causes:

Curved pipe surface

Inconsistent probe positioning

Rough metal surface

Poor coupling

Material irregularities

Solution: Improve probe contact and repeat the measurement using a suitable procedure.

Problem 3 - Incorrect Thickness Reading

Possible causes:

Incorrect sound velocity

Calibration error

Incorrect probe selection

Material differences

Surface coating interference

Solution: Verify the instrument using an appropriate reference and confirm the material properties.

Problem 4 - Difficulty Measuring Small Pipes

Possible causes:

Excessive pipe curvature

Probe contact limitations

Inappropriate probe size

Unsuitable measurement geometry

Solution: Check whether a compatible probe and appropriate ultrasonic measurement technique are available.

Problem 5 - Different Readings at Nearby Locations

Possible causes:

Actual wall thickness variation

Localized corrosion

Surface condition differences

Probe positioning differences

Measurement uncertainty

Solution: Repeat measurements systematically and investigate significant variations.

12. Pipe Wall Thickness Measurement for Preventive Maintenance

Preventive maintenance involves inspecting equipment regularly to identify deterioration before major operational problems develop.

Ultrasonic thickness measurement can support this process.

Typical Inspection Activities

Baseline Thickness Measurement

Record initial thickness values at established inspection locations.

Periodic Inspection

Repeat measurements according to the maintenance schedule.

Thickness Trend Monitoring

Compare current readings with previous records.

Engineering Review

Investigate significant reductions or readings outside established limits.

Maintenance Planning

Use the inspection findings to support decisions about further assessment, repair or replacement.

Benefits

Better Visibility of Equipment Condition

Improved Maintenance Documentation

Early Identification of Possible Wall Thinning

Support for Planned Maintenance

Reduced Unnecessary Dismantling

Inspection intervals should be established according to operating conditions, corrosion risks and applicable engineering requirements.

13. Industrial Applications in Malaysia

The Benetech GM100 Plus and GM130 Ultrasonic Thickness Gauges are relevant to various industrial sectors.

Manufacturing Factories

Thickness inspection of suitable metal pipelines and equipment components.

Water Treatment Facilities

Monitoring accessible metallic pipework and storage equipment.

Steel Fabrication Workshops

Thickness verification of suitable steel plates and fabricated components.

Mechanical Maintenance Contractors

Routine industrial equipment and pipeline inspection.

Petrochemical Facilities

Supporting appropriate thickness measurements on compatible metal components, subject to site safety and inspection requirements.

Engineering Companies

General metal thickness measurement and maintenance documentation.

These applications are relevant to customers in Selangor, Kuala Lumpur, Johor, Penang, Melaka, Negeri Sembilan, Perak, Pahang, Kedah, Kelantan, Terengganu, Perlis, Sabah and Sarawak.

14. GM100 Plus vs GM130 - Which Should You Choose?

Choose Benetech GM100 Plus If:

You need general pipe wall thickness measurement.

You mainly inspect suitable steel plates and pipes.

You require routine maintenance measurements.

You do not require thickness alarm settings.

You prefer a straightforward ultrasonic thickness gauge.

Choose Benetech GM130 If:

You need upper and lower thickness alarm settings.

You require metric and imperial unit conversion.

You want additional measurement mode options.

You need compatible 6 mm and 10 mm probe options.

You perform varied industrial thickness inspection tasks.

Both instruments can support pipe wall thickness measurement when the application falls within their verified measurement capabilities.

15. Frequently Asked Questions

Q1. How do you measure pipe wall thickness without cutting the pipe?

A suitable ultrasonic thickness gauge can measure wall thickness from one accessible side of the pipe using ultrasonic sound waves.

Q2. Can Benetech GM100 Plus measure steel pipe thickness?

Yes. The GM100 Plus can measure suitable steel pipe wall thickness when proper probe contact and measurement conditions are available.

Q3. What is the minimum thickness GM130 can measure?

The manufacturer specifies a steel measurement range beginning at 1.0 mm under the applicable reference conditions.

Actual minimum measurable thickness depends on probe selection and material conditions.

Q4. Do ultrasonic thickness gauges require coupling gel?

Yes. Suitable coupling agent is normally required to transmit ultrasonic energy between the probe and material.

Q5. Can an ultrasonic thickness gauge detect corrosion?

It can help identify possible wall thinning associated with corrosion.

However, it does not automatically detect every corrosion defect or determine equipment safety.

Q6. Can GM130 measure small-diameter pipes?

It may be possible with a suitable compatible probe and appropriate measurement conditions.

Pipe diameter and probe geometry must be evaluated.

Q7. Which is better for pipe inspection, GM100 Plus or GM130?

The GM100 Plus is suitable for general measurements, while the GM130 offers additional thickness alarm and probe options.

Q8. Where can I buy an ultrasonic thickness gauge in Malaysia?

MTM Precision Sdn Bhd supplies Benetech GM100 Plus and GM130 Ultrasonic Thickness Gauges for industrial maintenance and testing applications in Malaysia.

16. Buy Benetech GM100 Plus and GM130 Ultrasonic Thickness Gauge Malaysia

Looking for a reliable Pipe Wall Thickness Measurement Instrument in Malaysia?

MTM Precision Sdn Bhd supplies industrial testing and measuring instruments for manufacturing factories, engineering contractors, maintenance departments and inspection applications.

We supply:

Benetech GM100 Plus Ultrasonic Thickness Gauge

Suitable for routine steel plate and pipe wall thickness measurements.

Benetech GM130 Ultrasonic Thickness Gauge

Offers additional features including thickness alarm settings, measurement mode selection and compatible probe options.

Need Help Choosing a Suitable Model?

Please provide the following information:

Pipe Material

Pipe Diameter

Expected Wall Thickness

Surface Condition

Measurement Application

Probe Requirements

Special Inspection Requirements

Customers may send photographs of the pipe or equipment through WhatsApp for preliminary product selection assistance.

Contact MTM Precision Sdn Bhd

MTM PRECISION SDN BHD

Showroom & Service Centre:

No. 29-1 & 29-2, Jalan Bandar 18, Pusat Bandar Puchong, 47160 Puchong, Selangor, Malaysia.

Tel: 03-8080 7172

WhatsApp: +6016-660 7346

Email: mtmpre@yahoo.com

Website: www.mtmpre.com.my

Contact MTM Precision today for Benetech GM100 Plus and GM130 Ultrasonic Thickness Gauge enquiries, product availability and quotations in Malaysia.