IBERTEST Concrete testing and similar

MEH...PT - Four pre-stressed column, compression testing machine series, as per UNE-EN 12.390-4

Compression test machine, specifically designed to fulfil UNE-EN 12390-4 standard requirements, particularly those of sections 4.2.2 - table 1, 4.2.5 – table 2, Annex B, parts B.1.4 and B.6.2: fitted with self-blocking ball seating support and high rigidity testing frame.

This standard is in force since January 2004 and applies to all testing machines bought since then, and is compulsory for all accredited testing laboratories by ENAC (in Spain) or equivalent institutions (within the EU).

Matching MEH machine features with the standard requirements meant exhaustive redesign, computer-aided modelling and prototype tests. The outcome design has features only 4% result dispersion compared to 20% in the machine series compliant with the old standard.

In addition to ENAC calibration certificate, IBERTEST issues certificate of: upper-plate self-alignment; machine parts alignment; upper plate movement blocking; compression plates hardness, roughness and planarity; and CE-conformity certificate.

Technical specifications

Serie MEH... – Four column, compression machine series, as per UNE-EN 83.304

Compression testing machine fitted with self-blocking ball seating support and high rigidity, four column testing frame, hence suitable for compression testing of e.g. concrete specimens according to UNE 83304 standard

Technical specifications

Serie MEHP... – Welded structure, compression testing machine series, as per UNE 83.304

Simplified version of MEH…PT and MEH machine series, made of a welded and stabilized steel structure. Suitable for compression testing of e.g. concrete specimens according to UNE 83304 standard.

Technical specifications

Serie MEHB...H – Compression testing machine for special specimens such as blocks, bricks…

With some features and equipment similar to the MEH machines, it differs from them in the fact that the testing frame is equipped with an approximation screw-ball of the compression upper plate, manually activated, and with rectangular compression plates of 520 x 300 mm optionally up to 650 x 350 mm).

Made in versions of 1.500, 2.000 and 3.000 kN, this type of machines are mainly applied for testing bricks, blocks, etc., as well as in applications with specimens or elements to test of very different formats, which require a permanent checking of the distance between the compression plates.

Technical specifications

Technical Specifications Summary for the above machine series

Standards	UNE-EN 12390 (MEH...PT only), UNE 83304, DIN 51220, DIN 51302, BS 1610, BS 1881, AFNOR P 18-411, ASTM C 39 and ASTM C 1231
Testing frame	- 4 pre-stressed columns and self-blocking ball-seating support (MEH...PT) - 4 column and self-blocking, ball-seating support (MEH...) - 4 column, and upper plate setting by screw driver (MEHB...H) - Welded and stabilized steel structure (MEHP...)
Control system	- MDA & MDA/SV: Automatic, microprocessor-controlled digital module, programmable, fitted with functional membrane touch, emergency stop, Centronics and RS232 data output interfaces. - W & SW: Computer-based, featuring a PC with iPentiumIV microprocessor and 17” TFT flat colour screen, 32-bit WINTEST® software for MS Windows™ series and associated electronics. Emergency stop on the workbench.
Testing frame elements	- Baseplate and upper crossbeam in machined steel. - Piston with mobile jacket, so as to ensure the load axiality, and electric end-of-stroke. - Piston stroke: 60 mm. - Compression plates: hardened and ground, with controlled hardness, planarity and roughness (MEHB…H featuring rectangular ones). The lower plate with centring marks. - Standard ball seating (MEH...PT featuring self-blocking one) - Distance between compression plates: 320 mm (340 mm as an option)
Capacities available	1,000 – 1,500 – 2,000 – 2,500 – 3,000 kN (as an option for 4 column versions: 4,000 – 5,000 or 6,000 kN)
Accuracy class, as per ISO 7500	Class 1
Force measurement system	Pressure transducer of extensometrical bands in full bridge, with temperature compensation automatic circuit and air purge system
Scales	1/1 and 1/5 (1/10 for W versions)
Measurement range	2% to 100% of maximum capacity (1% to 100% for W versions)
Hydraulic unit	High-pressure leak-tight, anti-pollutant low-noise housing, fitted with filtering and safety systems, alarms and so on. Built inside a metallic bench, which houses the electrical board. On top of it, there is the control systems.
Closed-loop control system	- MDA series: proportional valve - MDA/SV, /SW and /W series: Moog servovalve
Number of measurement channels	- MDA & MDA/SV series: 2 channels - SW & W series: up to 16 channels
Air-oil heat exchanger	As an option (delivered as series equipment for W series)
Anti-projections safety system	- MEH...PT & MEH... series: whole perimeter, with frontal door in Makrolon and mechanical safety lock (electric in W versions). - MEHP... series: Frontal door in Makrolon and mechanical safety lock.
Collection tray for specimens smashes	Under the lower compression plate, with smashes collection takeaway trolley -as an option