TDT Inspection for Concrete Pumps – Coverage and Preparation

In Brief

TDT inspection for concrete pumps is a statutory obligation every 2 years (Technical Supervision Act). The inspector reviews: service documentation (2 years back), load-bearing boom structure welds (MT testing), hydraulics (1.25 × MOP for 10 minutes), and all safety devices. The most common causes of failure: weld cracks (40%), defective safety devices (25%), missing documentation (20%). Book your appointment at least 4–6 weeks before the certificate expires. PHS Magnum carries out pre-inspection checks and coordinates the TDT inspector — tel: +48 602 716 551.

TDT Inspection for Concrete Pumps – A Complete Guide

TDT inspection (technical examination by TDT) is a statutory obligation for every concrete pump operator in Poland — Aleksy Pasternak provides a broader overview of TDT technical supervision principles . But it is also a genuine safety benefit: the TDT inspector examines components that operators and routine servicing can overlook, yet which can lead to serious accidents.

Legal Basis – Who Requires TDT?

The obligation for technical supervision of concrete pumps derives from:

Technical Supervision Act (Article 14)

“Technical equipment may only be operated on the basis of an authorisation to operate, issued by the competent technical supervision authority.”

Penalties: Article 74 of the same Act — a fine or detention.

Scope: Which Equipment Is Covered?

• Concrete boom pumps with a boom length exceeding 22 m
• Trailer and stationary pumps operating at a maximum pressure above 40 bar
• Mixer pumps used commercially

What Does a TDT Inspector Examine?

Documentation Review

The inspector checks:

• The inspection log (maintenance journal) — completeness of entries
• Service inspection reports from the past 2 years
• Documentation of any modifications or welding repairs

Note: Missing service records are one of the most frequent grounds for refusing to proceed with an inspection. We maintain documentation on behalf of our clients and retain copies of all service reports.

Visual Inspection

A detailed visual examination covering:

• Condition of paintwork and anti-corrosion coatings (concealed cracks beneath the paint)
• All welds on the load-bearing boom structure
• Condition of outriggers and their mounting points
• Condition of hydraulic hoses (blistering, chafing, seepage)

Non-Destructive Testing (NDT)

For boom pumps, the inspector carries out (or commissions):

Magnetic Particle Testing (MT):

• Application of a powder suspension to welds
• Magnetisation of the test area
• Detection of cracks through powder accumulation at the fault line

Ultrasonic Testing (UT):

• Applied when subsurface cracking is suspected
• Typically used on heavy-wall welds (lower boom sections)

Hydraulic Pressure Test

Pump hydraulic system:

• Test pressure: 1.25 × MOP (Maximum Operating Pressure)
• Test duration: 10 minutes
• Requirements: no leaks, no permanent deformation

Safety Device Inspection

• Load Management System (overload limiter)
• Tilt sensor (level sensor)
• Outrigger interlocks
• Emergency STOP system
• Boom operation interlock when outriggers are not deployed

How to Prepare for TDT Inspection

4–6 Weeks Before

1. Book a pre-inspection check with PHS Magnum — we assess the machine’s condition and identify any repairs required before the TDT visit
2. Gather all documentation — service reports, operating manual, previous TDT certificate
3. Check the inspection log — confirm it is on the machine and all entries are legible

2–3 Weeks Before

Following the pre-inspection service check:

• Carry out all repairs identified by the service team
• Compile full service documentation
• Book a date with the TDT inspector (some regional inspectors have long waiting times — do not leave this to the last minute)

On the Day of Inspection

• Machine must be clean (the inspector needs to see welds and structural components)
• Hydraulic oil reservoir fully topped up
• Electrical systems functioning (lighting, safety signals)
• A trained operator available throughout the examination

Most Common Reasons for Failing TDT

Based on our 30+ years of service experience:

1. Cracks in load-bearing boom structure welds (invisible without MT) — 40% of failures
2. Defective safety devices — tilt sensor, interlocks — 25%
3. Absent or incomplete service documentation — 20%
4. Hydraulic system leaks (pressure leakage) — 10%
5. Wear of components: bolts, pins, boom bearings — 5%

Consequences of Failing TDT

If defects are identified, the inspector issues a decision refusing authorisation to operate. The machine cannot work until repairs are completed and a repeat examination passed.

The most serious situations involve operators who “forgot” about TDT and continued working with an expired certificate. At that point it is no longer an administrative matter — it becomes a criminal one.

Scheduling – Plan Ahead

TDT certification is valid for 2 years from the date of the previous examination.

We recommend:

• Calendar reminder: 3 months before expiry — initial assessment of machine condition
• 6 weeks before — pre-inspection service check
• 3–4 weeks before — complete repairs and book the inspector
• Inspection — with a comfortable buffer of several weeks

Call us on +48 602 716 551 with your pump’s serial number and we will advise what we check and how much preparation time is needed.

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