Hydrotechnik

Hydrotechnik, a German company, manufactures Minimess® couplings, sensors, and measuring devices for hydraulic system measurement and testing. The invention of Hydrotechnik Minimess® fittings enables air and oil measurement and sampling without reducing system pressure. The leading industrial and construction machinery companies prefer Hydrotechnik products for hydraulic measurement and testing applications. Hydrotechnik equipment is essential for various mobile and industrial hydraulic applications, particularly for controlling, observing, recording, and reporting variables like pressure, temperature, flow, pollution, torque, vibration, and pump, valve, or hydro motor speeds as graphics or tables while the system operates. Hydrotechnik is indispensable as auxiliary equipment for hydraulic technicians during periodic preventive maintenance, troubleshooting, R&D, and commissioning tasks.

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Complete Solution for Test Systems

• 10 Analog Sensor Inputs • 2 Analog Signal Inputs • 4 Frequency Signal Inputs • 6-14 Can Bus Signal Inputs • 4 Digital Signal Inputs • 2 Analog Signal Outputs • Free Formulation Virtual Channels • 0.1ms Sample Collection Rate • 10.4” Touch Screen • 6.000.000 Measurement Value Memory • 200 Separate Test Memory • Automatic Test and Measurement Programming with the HydroRun program

Multi System 5070

Multi System 4070

• Compact Test Solution Expandable structure of up to 15 channels • Battery-powered portable structure • 5 Analog/Frequency Sensor Inputs • 10 Pieces of Can Bus Signal Inputs • Freely Formulatable Virtual Channels • 1 ms Sample Collection Rate • 3.5” Color Screen • 2,000,000 Measurement Value Memory • 100 Separate Test Memory • Wireless data transfer with Bluetooth Kit

Multi Handy 3020

• Economic Tests • Battery-powered portable structure • 3 Analog/Frequency Sensor Inputs • Virtual Channels with Ready Formula • 1 ms Sample Collection Rate • Freely Formulatable Virtual Channels • 2.1” Mono Screen • 1.000.000 Measurement Value Memory • 14 Separate Test Memory

Multi Handy 2025

Minimess Connection Fittings

Hydrotechnik

Sensors

Hydrotechnik sensors used in hydraulic systems convert variable information (such as pressure, flow, and temperature) from the hydraulic circuit into analog and digital electronic signals, providing essential data. The types of sensors utilized in Hydrotechnik Hydraulic and Pneumatic systems vary according to the variable being measured:

Hydrotechnik

Pressure Sensors

Pressure sensors primarily convert system pressure values into electrical signals and transmit them to the relevant system. Aside from connection characteristics, the two most important features when describing pressure sensors are the measuring pressure range and output signal type. Measuring Pressure Ranges: (-1, +6 Bar), (0-1 Bar), (0-10 Bar), (0-25 Bar), (0-60 Bar), (0-100 Bar), (0-250 Bar), (0-400 Bar), (0-600 Bar), (0-1000 Bar) Regarding the measuring output signal, the device typically generates an analog signal. This signal can be a current or voltage output that changes according to the received pressure. The most preferred types are 0-10V and 4-20mA, but other output signals, such as (0-20mA), (1-5V), (2-10V), (0.5-4.5V), and (±10V), are also used.

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Temperature Sensors

Temperature sensors primarily convert the temperature values within a system into electrical signals and transmit them to the appropriate system.

Thermocouple

Thermocouple

Thermocouples and resistance thermometers are the most common types of temperature sensors. Thermocouples operate by connecting two different conductive materials end-to-end and calculating the voltage-temperature difference between them. The most frequently used types include K, J, T, E, and N types.

T type

Type T (copper-constantan) thermocouples are used between −200 and 350 °C. Its detection is approximately 43 µV/°C.

K type

Type K (chromal {90% nickel and 10% chromium} alumel {95% nickel, 2% manganese, 2% aluminum and 1% silicon}) is the most general-purpose thermocouple. Its detection is approximately 41 µV/°C. Their cost is low and probes It is used between −200 °C and +1250 °C.

E type

Type E (chromal-constantan {55% copper and 45% nickel}), its detection is 68 µV/°C. That's why it is used in cryogenics. It is also non-magnetic. It is used between −50 and 740 °C. Cable color standard, purple (+) and red (-)

J type

Type J (iron-constantan), the temperature range is very limited. But its detection is about 55 µV/°C. Curie temperature (770 °C), which determines the upper temperature limit of iron, causes a sudden change in the characteristics of iron.

N type

N type (nicrosyl {14.4% chromium, 1.4% silicon and 0.1% magnesium}-nisil {nickel and 4.4% silicon}) thermocouples are used between −270 °C and 1300 °C. Their detection is approximately 39 µV/°C at 900 °C. Type B, R, and S thermocouples use either platinum or a platinum-rhodium alloy in each conductor. It has lower detection than other types and is about 10 µV/°C.

Hydrotechnik

Resistance Thermometer

Resistance thermometers are the most commonly used sensors in industry and laboratories, particularly for troubleshooting applications. These sensors measure temperature by interpreting the change in resistance of a conductive wire, typically platinum or nickel wires known as Pt100. Pt100 sensors output in ohms, reading the varying resistances of the two wires placed within a metal sheath. The most preferred measuring pressure range is -50 to +200 °C. For the output signal, ohm or 4-20mA are the most popular choices.

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Hydrotechnik

Flow Sensors

Flow sensors convert the flow value on the line where they are mounted into electrical signals and transmit them to the appropriate system. Working principle types include: • Turbine type • Gear type • Electromagnetic • Ultrasonic • Float • Thermal Mass • Vortex • Venturi and more.

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Hydrotechnik

Gear Type Flowmeters

Gear flow meters have a measurement accuracy between 0.1% and 0.5%, making them more popular in test and R&D systems. Viscosity ranges span from 5-120,000 cSt, and working pressures range between 350 and 630 Bar.

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Turbine Type Flowmeters

Accurate calibration of measurement and electronic systems involves carefully inputting the table values from the manufacturer's calibration certificates into the relevant system to prevent errors. Most manufacturers now embed calibration data into the sensor with smart recognition chips, allowing for automatic calibration when inserted into the same manufacturer's measuring device. Measurement sensitivities are 0.5%, viscosity ranges from 1-150 cSt, and working pressures range from 350 to 420 Bar.

Hydrotechnik

Speed Sensors

Speed sensors measure the revolutions of electric and hydro motors driving the pumps in hydraulic systems. Measurements can be taken from mechanical bodies with magnetic sensors and reflective and non-reflective sensors that measure with light.

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Hydrotechnik

Position Sensors

Position sensors, also known as linear rulers, are linear position-reading sensors mounted on mechanical parts or placed in hydraulic cylinders to provide instant position information for the automation system to act accordingly. Analog output signals include 4-20 mA or 0-10V.

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Force Sensors: (Load Cells)

Force sensors measure the force created by hydraulic systems and can be applied to mechanical systems driven by the hydraulic system or at the shaft end of hydraulic cylinders. Suitable sensors for pulling, pushing, stretching, and buckling are available, as well as Lama type, S type, Compression type, and Platform type sensors based on their shapes. Signal output type is mv/V.

Hydrotechnik

Torque Sensors

Torque sensors in hydraulic systems are mounted between electric motors and pumps or between hydro motors and the mechanisms they drive. Rated values include rated torque range, maximum speed, mass moment of inertia (driving side and measuring side), lateral forces, and output signal.

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Vibration Sensors

Vibration sensors have different connection types, with some products featuring metric gear. Some connect directly to the pump or motor body with a threaded bolt, while magnetic products attach directly to the body, as shown in the photo. Output signals range from 1-100 Hz, and measurement ranges span from 1-50g.

Particle Contamination Measurement Sensor

Solid particle pollution is a significant threat to hydraulic systems. Pollution can originate externally or from the breakdown of worn-out internal components. As a result, pollution measurement is crucial for efficiently using hydraulic systems. In the 2000-2010s, measurement systems could only be used in low-pressure lines, allowing measurements on tank lines or off-line low-pressure transfer and filtration lines. Recently, new products have been developed to withstand 420 Bar dynamic and 600 Bar static pressure, enabling connection to any point in the system without stopping, using minimess®.

Pollution-measuring sensors operate on the principle of measuring light and shadow. The output measurements are based on the particles in every 100 ml oil. Calibrations are conducted with test powder according to ISO11943. Output result types include ISO4406:99, SAE AS4059E, NAS1638, and GOST 17216.

Hydrotechnik

Pollution Value Reporting

Sensors for pollution value reporting provide data in several ways: • Own Memory: These sensors store up to 250 test data points, which you can access and report using a program. • Online Measurements: By working with a computer program, these sensors send real-time results and accumulated test data to the computer for reporting. • Analog Output: The sensors give a 4-20 mA output signal in a specific sequence for four distinct measurements within a set time period, allowing integration with the current electronic system to access the values. • Switch Output: Based on the requirements of the system in use, a switch gets incorporated into the measurement sensor. The pollution level gets recorded, and a contact signal gets sent externally when the measurement reaches this level. • RS232 or CanBus Signal: Use this output signal to connect to the measuring device or SCADA system, enabling continuous data transmission.

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Hydrotechnik

Oil Analysis Sensors

Oil analysis sensors measure and report particulate pollution, moisture content, dielectric coefficient, viscosity, metal pollution, and hydraulic oil temperatures. The oil flow first enters the particle sensor, passes through a pressure reducer (for high pressure), and then reaches the humidity and viscosity sensors. Optionally, you can add a metal contamination sensor to the system. If preferred, you can use these sensor outputs individually in measurement systems or collect and analyze the data via Can Bus in a measuring device. The goal is to maintain complete control to prevent oil-related issues. These sensors ensure continuous analysis across different hydraulic systems within an organization. By comparing measurements taken at specific intervals with previous results, the system aims to prevent malfunctions by determining oil life and aging time and identifying the types of pollutants present.

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Hydrotechnik

Current and Voltage Sensors

Current and voltage sensors collect control signals applied to proportional and servo valves in hydraulic systems. When testing proportional or servo systems, these sensors enable data collection of the signal applied to the proportional valve, along with values read by the pressure sensor and flowmeter connected to the system. This data can then be examined on the same graph.

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Level Sensors

Level sensors employed in hydraulic and pneumatic measurement and troubleshooting techniques report the oil level, relative humidity, dielectric coefficient, conductivity, and temperature within the oil. These sensors connect to electronic systems with two configurable 4-20mA signal outputs and RS232 and Can Bus outputs. When installed as a fixed component, these sensors offer continuous data feeds to SCADA.

Hydrotechnik

Measuring Points and Special Connection Unions

The hydraulic system typically needs to be stopped to mechanically connect all the sensors and other measuring devices mentioned above to hydraulic systems. Naturally, this causes interruptions or delays in taking measurements. Hydrotechnic has designed special measuring points to prevent stoppages while connecting measuring devices to the system. These products allow for easy connection or disconnection while the hydraulic system is operating. Pressure, temperature, pollution, oil analysis sensors, and standard pressure gauges (manometers) can be connected to these fittings, known as test ports or Minimess®.

Hydrotechnik

Minimess® Connecting Union Structure

Developed by "Hydrotechnik" in the 1950s, Minimess® connection unions are special fittings that offer safe and leak-free connections to high-pressure lines. Machinery and hydraulic power unit manufacturers incorporate these unions at critical points and on blocks during system design, ensuring accessible intervention for long-term maintenance, analysis, and short-term commissioning without stopping the system. A well-designed hydraulic power unit cannot be imagined without Minimess®. The internal structure of Minimess® unions consists of male threaded fittings on both sides and a hexagonal key holding area in the middle, as illustrated below. A chain cover has been developed to protect the interface from dust and other contaminants when Minimess® is not in use.

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Hydrotechnik

Minimess® Connecting Union Types

Minimess® couplings come in various types, with the most widely used being those with an M16x2 (covered part) connection interface, providing DN2 diameter permeability. Other Minimess® glands include M12x1.5, M16x1.5, and M16x4 connection interfaces. In the block connection section, options are vast. The most commonly used type is the 1/4" BSP male threaded product. BSP thread options include 1/8", 3/8", and 1/2" products. Additionally, threaded products in Metric, UNF, NPT, and JIC standards are available. Minimess® unions, categorized into four types based on their connection interfaces, are primarily developed for different applications: • M16x2 products are used in hydraulic lines, standard industrial, and mobile systems. • M12x1.5 products, with their compact structure, are suitable for industrial and mobile systems in confined spaces. • M16x1.5 military products are designed for hydraulic lines and gas lines. • M16x4 DN4 diameter products are used in hydraulic lines and locations that require flow. Minimess® couplings also have products developed for connecting to the installation, besides male thread connections in block connection parts. Various types are shown in the accompanying photos.

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Special Minimess® Unions

Minimess® Connection Hoses

Minimess® hoses are used when sensors or indicators need to be placed far from the Minimess® fittings in the system. Generally produced for DN2, these hoses can also be made for DN4 for special requirements. The outer layers consist of TPE, while the inner layers are Kevlar and Polyamide. The hoses have 400 and 630 Bar working pressures, and some can operate at unusual temperatures. Suitable caps are pressed according to the intended use. One side connects to Minimess® unions, while the other is produced with the required connection structure.

Hydrotechnik

Measurement and Reporting of Variables in Hydraulic Systems

In all types of mobile and industrial hydraulic applications, such as during operation or testing of pumps, valves, working elements, cylinders, and hydro-motors, measurements are taken to control, observe, and record various variables like pressure, temperature, flow rate, and pollution levels. These measurements can then be recorded and reported as graphs or tables. If needed, measurements can be taken at microsecond intervals.

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