Ultrasonic Thickness Gauge for Steel Corrosion Monitoring and Preventive Maintenance Malaysia

Ultrasonic Thickness Gauge for Steel Corrosion Monitoring and Preventive Maintenance Malaysia

Introduction

Steel corrosion monitoring is an important part of industrial preventive maintenance in Malaysia. Manufacturing factories, water treatment plants, engineering facilities and industrial contractors regularly inspect metal equipment to identify deterioration before major failures occur.

Steel pipelines, storage tanks and mechanical components may gradually lose wall thickness due to corrosion, erosion, chemical exposure and long-term operating conditions.

One practical method for monitoring possible wall thinning is ultrasonic thickness measurement.

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

By recording thickness measurements at established inspection locations over time, maintenance teams can monitor changes and identify areas requiring further assessment.

This guide explains how ultrasonic thickness gauges support steel corrosion monitoring, thickness trend analysis and preventive maintenance programs in Malaysian industries.

1. What Is Steel Corrosion Monitoring?

Steel corrosion monitoring involves inspecting metal components to identify deterioration associated with chemical or electrochemical reactions.

Corrosion can gradually reduce the thickness of metal equipment.

Common industrial components affected by corrosion include:

Steel Pipelines

Water Storage Tanks

Industrial Process Tanks

Cooling Water Systems

Metal Equipment Housings

Steel Fabricated Structures

Industrial Utility Piping

Mechanical Components

Corrosion may occur on the external surface, internal surface or both.

Why Is Corrosion Monitoring Important?

Identify Possible Wall Thinning

Thickness measurements can help reveal material loss at selected inspection locations.

Support Preventive Maintenance

Inspection findings can help maintenance teams plan further assessment or repair.

Improve Equipment Records

Repeated measurements provide information about changes in material thickness.

Support Engineering Decisions

Thickness data can be used alongside operating conditions and applicable engineering requirements.

Reduce Unexpected Equipment Problems

Appropriate inspection programs may help identify deterioration before serious damage develops.

However, ultrasonic thickness measurements do not automatically identify every corrosion defect.

2. How Does an Ultrasonic Thickness Gauge Detect Wall Thinning?

An Ultrasonic Thickness Gauge uses high-frequency sound waves to measure material thickness.

The probe transmits ultrasonic energy into the material.

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

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

Basic Formula

Thickness = Sound Velocity × Echo Travel Time / 2

For reliable measurement, the operator must use the correct material sound velocity and suitable ultrasonic coupling.

Example

Suppose a steel pipe has a baseline thickness reading of 6.0 mm.

During a later inspection, the same location produces a verified reading of 5.7 mm.

This may indicate a reduction in wall thickness.

However, the difference should be evaluated against measurement uncertainty, surface conditions and inspection consistency before concluding that corrosion has occurred.

Thickness measurement is a method of monitoring possible material loss, not a complete corrosion diagnosis.

3. Benetech GM100 Plus and GM130 for Corrosion Monitoring

Both instruments can support routine thickness measurements.

SpecificationGM100 PlusGM130Steel Measuring Range1.2–300 mm1.0–300 mmWorking Frequency5 MHz5 MHzSound Velocity Range1000–9999 m/s1000–9999 m/sAutomatic CalibrationYesYesLinear Automatic CompensationYesNoThickness Value StorageYesYesCoupling Status IndicationYesYesThickness AlarmNoYesMeasurement Mode SelectionNoYesMetric / Imperial ConversionNoYes6 mm Probe SupportNoYes10 mm Probe SupportYesYes

Important: The specified measuring ranges are based on the manufacturer's steel reference conditions. Actual measurement capability depends on material properties, probe selection and inspection conditions.

Benetech GM100 Plus

The GM100 Plus is suitable for general thickness measurement of compatible steel plates, pipes, storage tanks and machinery components.

Benetech GM130

The GM130 provides additional features including thickness alarm settings, measurement mode selection and compatible 6 mm and 10 mm probe options.

These features may be useful for repeated inspection work where technicians need additional measurement flexibility.

4. What Is Preventive Maintenance?

Preventive Maintenance involves scheduled inspection and maintenance activities intended to reduce the likelihood of equipment deterioration or unexpected failure.

For industrial metal equipment, preventive maintenance may include:

Visual inspection

Corrosion assessment

Wall thickness measurement

Leak inspection

Equipment condition monitoring

Maintenance documentation

Planned repair or replacement

Role of Ultrasonic Thickness Measurement

Ultrasonic thickness gauges provide measurement data that can support equipment condition assessment.

For example, a maintenance team may establish thickness monitoring locations along a steel pipeline.

Readings collected during later inspections can be compared with the baseline measurements.

Significant changes may indicate a need for additional inspection.

Benefits for Malaysian Factories

Better Maintenance Planning

Maintenance teams can use inspection findings to prioritize further investigation.

Improved Documentation

Recorded thickness values support maintenance history tracking.

Reduced Unnecessary Dismantling

Suitable components can often be measured from one accessible side.

Early Identification of Possible Material Loss

Repeated measurements may reveal deterioration trends.

Support for Risk-Based Maintenance

Thickness information can contribute to broader equipment condition and risk assessments.

5. How to Establish a Steel Thickness Monitoring Program

A useful corrosion monitoring program requires more than taking occasional thickness readings.

Measurements should be collected consistently and recorded properly.

Step 1 - Identify Equipment for Monitoring

Select equipment according to its operating conditions, corrosion risks and maintenance requirements.

Examples include:

Steel pipelines

Storage tanks

Industrial process piping

Cooling water systems

Metal equipment components

Step 2 - Establish Inspection Locations

Select measurement points according to the inspection plan.

Locations may include areas with known corrosion risks, previous deterioration or relevant operating conditions.

Step 3 - Record Baseline Thickness

Measure and document the initial wall thickness at each established location.

Where available, compare measurements with reliable historical records or design information.

Step 4 - Verify the Instrument

Check the ultrasonic thickness gauge using a suitable reference sample.

Confirm the material sound velocity and probe selection.

Step 5 - Perform Measurements

Prepare the surface, apply coupling agent and obtain stable thickness readings.

Step 6 - Record Results

Document the measurement location, date, thickness and relevant inspection conditions.

Step 7 - Compare Historical Data

Compare current readings with previous measurements at the same location.

Step 8 - Investigate Significant Changes

Unexpected thickness reduction should be verified and assessed according to an appropriate inspection procedure.

A consistent monitoring method is essential for meaningful thickness trend analysis.

6. Example of Long-Term Steel Thickness Monitoring

Consider a hypothetical steel pipeline monitored over several years.

Inspection YearMeasured Thickness20236.0 mm20245.9 mm20255.7 mm20265.5 mm

Illustrative example only. These values are not actual field measurements.

The recorded thickness decreases from 6.0 mm to 5.5 mm over three years.

Estimated Average Thickness Loss Rate

Thickness Loss = Initial Thickness - Latest Thickness

Thickness Loss = 6.0 - 5.5 = 0.5 mm

Average Thickness Loss Rate = 0.5 mm / 3 Years

Estimated Average Loss Rate = 0.167 mm per year

This calculation provides a simple historical average.

Important Limitations

The estimated loss rate assumes that:

Measurements were taken at the same location.

Instrument settings were appropriate.

Measurement uncertainty was controlled.

The recorded thickness difference represents actual material loss.

Actual corrosion rates may change over time.

Historical average thickness loss should not be treated as a guaranteed future corrosion rate.

For critical equipment, remaining life and inspection intervals should be determined using applicable engineering methods and standards.

7. How to Create a Thickness Inspection Record

Good documentation is essential for effective preventive maintenance.

A basic inspection record may include:

InformationExampleEquipmentCooling Water PipeInspection PointCW-01MaterialCarbon SteelInstrumentBenetech GM130ProbeCompatible 10 mm ProbeInspection Date11 October 2026Measured Thickness5.8 mmSurface ConditionCleaned Metal SurfaceInspectorMaintenance Technician

Example record only.

Why Inspection Records Matter

Historical Comparison

Records allow technicians to compare readings over time.

Maintenance Planning

Thickness trends may help identify areas requiring additional assessment.

Inspection Consistency

Defined locations reduce confusion during repeat measurements.

Equipment Documentation

Records support maintenance history and engineering review.

Recommended Recordkeeping Practice

Maintain consistent equipment identification and inspection point references.

Where practical, use photographs, location diagrams or permanent measurement point markings.

The GM100 Plus and GM130 offer thickness value storage functions, but customers should confirm the actual storage capacity and data handling requirements before purchasing.

8. Using GM130 Thickness Alarm for Preventive Maintenance

The Benetech GM130 includes upper and lower thickness alarm settings.

This function can assist with repeated thickness screening.

Example

Suppose a qualified engineer establishes a lower inspection screening threshold of 4.5 mm for a specific component.

The technician configures the GM130 lower alarm setting according to the approved inspection procedure.

Measured ThicknessScreening Result5.5 mmAbove threshold4.9 mmAbove threshold4.5 mmAt threshold4.2 mmBelow threshold

Illustrative example only. The 4.5 mm threshold is not a universal minimum safe thickness.

Advantages of Thickness Alarm Settings

Faster Screening of Multiple Measurement Points

Convenient Identification of Out-of-Range Readings

Support for Routine Maintenance Inspection

Improved Measurement Screening Consistency

However, the alarm function does not determine whether equipment is safe.

Minimum allowable thickness must be established according to the relevant engineering requirements.

9. Steel Pipeline Corrosion Monitoring

Steel pipelines are widely used in Malaysian manufacturing and industrial facilities.

Common applications include:

Cooling water pipelines

Compressed air piping

Industrial process piping

Water distribution systems

Utility piping

Common Corrosion Concerns

Internal Corrosion

May develop due to the transported fluid, contaminants or operating conditions.

External Corrosion

May occur due to moisture, environmental exposure or coating deterioration.

Localized Pitting

May cause severe material loss in small areas.

Erosion-Corrosion

May occur in certain flowing systems under particular operating conditions.

How Ultrasonic Thickness Gauges Help

The GM100 Plus and GM130 can measure remaining wall thickness at suitable inspection locations.

Repeated measurements may help identify thickness reduction trends.

However, limited point measurements may miss localized defects.

For critical corrosion assessment, additional NDT techniques or more extensive inspection coverage may be necessary.

10. Storage Tank Corrosion Monitoring

Industrial storage tanks may experience corrosion due to stored materials, moisture and environmental exposure.

Typical monitoring locations may include:

Tank shell sections

Lower wall areas

Accessible metal surfaces

Previously identified corrosion locations

Established inspection points

Recommended Approach

Identify Inspection Points

Select locations according to the inspection plan.

Prepare the Surface

Remove loose contamination that interferes with ultrasonic coupling.

Verify the Instrument

Confirm sound velocity, probe suitability and measurement performance.

Measure Wall Thickness

Take readings according to the inspection procedure.

Record and Compare

Compare results with previous measurements.

Important Limitation

A few ultrasonic thickness readings cannot establish the overall integrity of a storage tank.

Comprehensive tank inspection may require specialized methods and qualified personnel.

11. Common Problems During Corrosion Thickness Measurement

Problem 1 - Unstable Readings on Corroded Steel

Possible causes:

Rough surface

Poor coupling

Irregular internal corrosion

Probe positioning problems

Solution: Improve surface preparation, verify coupling and repeat measurements using an appropriate procedure.

Problem 2 - Unexpected Thickness Reduction

Possible causes:

Actual material loss

Different measurement location

Incorrect sound velocity

Calibration problems

Measurement uncertainty

Solution: Verify the measurement before interpreting the result.

Problem 3 - No Thickness Reading

Possible causes:

Insufficient coupling gel

Poor probe contact

Unsuitable surface condition

Incorrect settings

Solution: Check the instrument, probe and measurement surface.

Problem 4 - Incorrect Readings on Painted Steel

Protective coatings may affect conventional ultrasonic thickness measurement.

Solution: Confirm whether coating removal or a specialized through-coating instrument is required.

Problem 5 - Difficulty Measuring Small Pipes

Pipe curvature may interfere with probe contact.

Solution: Confirm the pipe diameter and select an appropriate compatible probe or measurement method.

12. Can Ultrasonic Thickness Gauges Measure Through Paint?

Many steel pipelines and storage tanks have protective coatings.

These coatings help reduce environmental exposure and corrosion.

However, conventional ultrasonic thickness measurements may be influenced by coating thickness.

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

If a customer needs to measure the remaining metal thickness without removing paint, a suitable through-coating instrument may be required.

For conventional measurements, approved coating removal at selected inspection points may be necessary.

13. How Often Should Thickness Monitoring Be Performed?

There is no single inspection interval suitable for every industrial component.

Inspection frequency depends on:

Material Type

Operating Conditions

Corrosion Risk

Previous Inspection Results

Equipment Criticality

Applicable Standards

Regulatory Requirements

For example, a component exposed to aggressive chemical conditions may require more frequent inspection than equipment operating in a relatively mild environment.

Recommended Maintenance Approach

Baseline Inspection

Establish initial thickness measurements.

Scheduled Monitoring

Repeat measurements according to the approved inspection plan.

Trend Analysis

Compare current and historical readings.

Further Investigation

Investigate significant thickness changes.

Engineering Review

Use qualified assessment to determine appropriate maintenance actions.

Inspection intervals should be established according to actual risk and applicable engineering requirements, not arbitrary schedules.

14. GM100 Plus vs GM130 for Preventive Maintenance

Choose Benetech GM100 Plus If:

You need routine metal thickness measurement.

You mainly inspect suitable steel plates and pipes.

You perform general factory maintenance.

You do not require thickness alarm settings.

You prefer straightforward measurement operation.

Choose Benetech GM130 If:

You require upper and lower thickness alarms.

You need measurement mode selection.

You want metric and imperial unit conversion.

You require compatible 6 mm and 10 mm probe options.

You perform varied industrial thickness inspection tasks.

For general thickness monitoring, the GM100 Plus is a practical choice. For additional screening features and probe flexibility, consider the GM130.

15. Industrial Corrosion Monitoring Applications in Malaysia

The Benetech GM100 Plus and GM130 Ultrasonic Thickness Gauges are relevant to industrial maintenance applications throughout Malaysia.

Selangor and Kuala Lumpur

Factory maintenance, industrial piping and mechanical equipment inspection.

Johor

Manufacturing plants, water treatment facilities and steel fabrication workshops.

Penang and Kedah

Industrial manufacturing, mechanical engineering and equipment maintenance.

Melaka and Negeri Sembilan

Factory equipment, storage tanks and industrial maintenance.

Perak and Pahang

Industrial processing plants, engineering facilities and metal thickness inspection.

Terengganu and Kelantan

Suitable industrial piping and equipment corrosion monitoring.

Sabah and Sarawak

Industrial facilities, storage equipment and mechanical maintenance.

Engineering customers in Perlis may also require portable ultrasonic thickness gauges for general industrial applications.

16. Frequently Asked Questions

Q1. What is an ultrasonic thickness gauge used for in corrosion monitoring?

It measures the remaining thickness of suitable materials and helps technicians monitor possible wall thinning over time.

Q2. Can Benetech GM100 Plus detect corrosion?

The GM100 Plus can help identify possible corrosion-related thickness reduction at measured locations.

It does not automatically detect every corrosion defect.

Q3. Is GM130 suitable for preventive maintenance?

Yes. The GM130 can support routine thickness monitoring and offers additional features such as upper and lower thickness alarms.

Q4. How do you calculate average thickness loss?

Subtract the latest verified thickness from the baseline thickness and divide by the elapsed time.

The result is a historical average and should be interpreted with measurement uncertainty and operating conditions in mind.

Q5. Can ultrasonic thickness gauges measure steel tanks?

Yes. Suitable accessible steel tank walls can be measured using an appropriate ultrasonic thickness gauge and inspection procedure.

Q6. Can GM130 measure through paint?

Do not assume that GM130 provides specialized through-coating thickness measurement.

Q7. How often should industrial steel thickness be checked?

Inspection frequency depends on corrosion risk, operating conditions, equipment criticality and applicable requirements.

Q8. Can ultrasonic thickness measurements determine remaining equipment life?

Thickness measurements can provide useful input for engineering calculations, but remaining life assessment requires additional information and qualified evaluation.

Q9. Which is better for corrosion monitoring, GM100 Plus or GM130?

Both can support routine thickness measurement.

The GM130 provides additional alarm and probe options, while the GM100 Plus is suitable for general measurement applications.

Q10. 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 testing and maintenance applications in Malaysia.

17. Buy Benetech Ultrasonic Thickness Gauge for Corrosion Monitoring Malaysia

Looking for a reliable Ultrasonic Thickness Gauge Supplier in Malaysia?

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

We supply:

Benetech GM100 Plus Ultrasonic Thickness Gauge

Suitable for general thickness measurement of compatible steel plates, pipelines, storage tanks and industrial metal components.

Benetech GM130 Ultrasonic Thickness Gauge

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

Need Help Selecting the Right Model?

Please provide:

Material Type

Expected Thickness Range

Pipe Diameter or Component Dimensions

Surface Condition

Inspection Application

Probe Requirements

Thickness Alarm Requirements

Calibration Requirements

Customers may send photographs of their equipment or measurement locations 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.