UNI-T UT343E for Steel Structure Paint and Protective Coating Inspection Malaysia
UNI-T UT343E for Steel Structure Paint and Protective Coating Inspection Malaysia
Content
Published: 1 October 2026
The UNI-T UT343E Coating Thickness Gauge can be used to check suitable paint and protective coatings applied over steel structures, fabricated components and industrial equipment.
Its 0–2000μm range, ferrous-substrate measurement, limit alarms and digital data functions help contractors and quality-control teams identify areas with insufficient or inconsistent coating thickness.
Why Check Protective Coating Thickness?
Steel structures are commonly coated to reduce exposure to moisture, chemicals and corrosive environments.
If the coating is too thin, the steel may not receive the intended protection. If it is unnecessarily thick, the project may experience excessive material use, curing problems or finishing defects.
Thickness inspection helps verify whether the applied coating meets the approved project specification.
Suitable Steel Applications
The UT343E may be used on suitable coated steel surfaces such as:
- Structural steel components
- Steel columns and beams
- Storage tanks
- Fabricated frames
- Machinery housings
- Steel platforms
- Handrails and barriers
- Industrial piping exteriors
- Equipment skids
- Painted metal enclosures
The surface must provide enough area for the probe to make proper contact.
Confirm the Required Thickness
The UT343E does not determine the correct coating thickness automatically.
The acceptance range must come from:
- Project specifications
- Coating manufacturer requirements
- Engineering drawings
- Customer requirements
- Approved inspection procedures
- Coating-system documentation
Multi-layer coating systems may include primer, intermediate coat and topcoat. Confirm whether the required value refers to one layer or the total dry-film thickness.
Check the Surface Before Measurement
The coated surface should be:
- Dry
- Fully cured
- Free from dust
- Free from water
- Free from oil
- Stable and undamaged
- Safe to access
Loose rust, surface contamination, uncured coating or severe roughness can affect the measurement.
Do not measure on wet paint unless the instrument and procedure are specifically intended for that application.
Perform a Reference Check
Before starting site measurements:
- Clean the UT343E probe.
- Use the supplied ferrous reference plate.
- Check the uncoated plate.
- Place a standard coating film on the plate.
- Take several readings.
- Confirm that the readings are stable.
A reference check confirms basic instrument response. It does not replace formal calibration when traceable results are required.
Plan the Measurement Locations
Do not check only the easiest flat surface.
A practical inspection may include:
- Main flat sections
- Corners and edges
- Welded areas
- Bolted connections
- Areas near openings
- Upper and lower faces
- Difficult spray locations
- Sections exposed to weather or chemicals
- Repaired or touched-up areas
Measurement locations should follow the approved inspection plan whenever one is available.
Why Edges and Welds Need Attention
Coating thickness may differ around edges, corners and welds because of:
- Difficult spray-gun access
- Coating flow and surface geometry
- Stripe-coat application
- Surface preparation differences
- Overspray or excessive build-up
- Touch-up work after fabrication
These areas may be important to corrosion protection, but they can also be difficult to measure accurately.
Take several readings and avoid placing the probe directly on an unsuitable sharp edge.
Use Multiple Readings
One result cannot represent an entire beam, tank or fabricated structure.
Take multiple readings from each inspection area and review:
- Minimum value
- Maximum value
- Average value
- Variation between nearby points
- Results outside the approved range
A satisfactory average should not be used to ignore individual readings below a specified minimum.
Set Upper and Lower Limits
The UT343E allows the operator to enter upper and lower coating limits.
The LED and audio alarm can help identify measurements outside the selected range during repeated inspections.
This feature is useful when checking many components, but inspectors should still record the actual values and measurement locations.
Store Inspection Records
The UT343E can store up to 3300 readings and supports Bluetooth App and PC data analysis.
Useful inspection information includes:
- Project name
- Component identification
- Coating system
- Steel-surface location
- Required thickness range
- Actual readings
- Inspection date
- Inspector’s name
- Repaired or rejected areas
Well-organised records help with quality review, contractor discussions and follow-up inspection.
Common Reasons for Low Readings
Low coating thickness may result from:
- Insufficient paint application
- Difficult access
- Poor edge coverage
- Incorrect spray technique
- Excessive thinning
- Missed areas
- Surface-profile effects
- Damage during handling or installation
Repeat the reading and inspect nearby points before deciding on corrective action.
Common Reasons for High Readings
High readings may result from:
- Excessive coating application
- Multiple touch-up layers
- Coating build-up at corners
- Repainting
- Overlapping spray passes
- Localised repair
- Surface contamination beneath the probe
Confirm the instrument setup and inspect the surface condition before classifying the result as non-compliant.
UT343E Does Not Measure Steel-Wall Thickness
The UT343E measures the coating over the steel, not the thickness of the steel itself.
For checking:
- Corrosion-related wall loss
- Pipe-wall thickness
- Tank-plate thickness
- Remaining steel thickness
An ultrasonic thickness gauge such as the UNI-T UT345A is the more appropriate instrument.
Some industrial inspections may require both instruments: the UT343E for protective coating and the UT345A for base-material thickness.
Important Safety Considerations
A coating thickness gauge does not make an unsafe area safe to access.
When inspecting structures, tanks or elevated locations:
- Follow the site permit system
- Use appropriate fall protection
- Confirm confined-space requirements
- Observe chemical and electrical hazards
- Do not enter restricted areas without authorisation
- Follow the project’s safety procedures
Instrument selection and site-access safety must be evaluated separately.
Who Should Use the UT343E?
The UNI-T UT343E is suitable for:
- Steel fabricators
- Painting contractors
- Protective-coating inspectors
- Factory quality-control teams
- Maintenance departments
- Equipment manufacturers
- Construction contractors
- Incoming inspection teams
Companies in Selangor, Kuala Lumpur, Johor and Penang can use it for suitable steel-paint and protective-coating applications.
For product availability or assistance selecting a coating thickness gauge, send MTM Precision the coating system, steel component photo and expected thickness range.
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
01 Oct 2026
