Hydraulic Test Bench

The test bench is used to verify special features of protective relays. These are components of onload tapchanger in current transformers. The protective relay is installed between onload tapchanger head and oil conservator. It is used to check the oil flow speed and is triggered when the specified oil flow is exceeded. With the test bench the oil flow speed from various types can be tested when the inside flap of the protective relays responds.

FNC pre-assembly line

This pre-assembly line designed and constructed by Sonplas prepares the brake pistons required for the final assembly of floating-type brake callipers. The preassembly line feeds and assembles the 9 individual components to produce the complete brake piston. In order to fit all the assembly processes into the smallest space possible, the line has a rigid, stepping conveyor and a rotary table for the part assembly steps. The assembled parts are placed onto the conveyor belts of the two assembly lines by an ADEPT COBRA scara robot. The line also has a special reworking mode for processing parts which are already in various stages of assembly. The reworking mode can also be used to pre-assemble prototype series on the line.

Automated assembly machine for Eurocaps

Eurocaps are component parts of infusion lines and are designed to vent the infusion bottle during the slow emptying process. Eurocaps are fitted with filters to prevent foreign substances or germs from entering the bottle. The automated assembly unit feeds Eurocaps (supplied in bulk) into the filter insertion station where discs of filter paper are punched from a roll and are then pressed into the Eurocaps. At the final stage of the assembly cycle, a precision pressure switch increases and then decreases the pressure to test the presence and function of the filters. In order to increase the output the machine processes ten caps at the same time. The caps are transported through the machine by means of a parallel gripper.

CNG injector calibration & test

The test bench has been designed to support customers in research and development of CNG injectors. It offers high flexibility in calibrating and testing injectors with different geometries due to a simple change of the injector nest. Voltage remote control via software and various driver boards are included in this configuration as well. The fully automated control software determines the most important process parameters which characterizes the injector’s operating method. This includes dynamic and static flow, static and dynamic minimum operating voltage, opening and closing time as well as the linearity of the injector.

Starter-alternator test conditioning unit

In order to drive the starter-alternator unit and to ensure accurate results from parameter and endurance tests, it is important to carry out the tests in an environment similar to real vehicle operating conditions. The test conditioning unit consists of three separate heating-cooling circuits and has been designed for conditioning test parts. This unit controls the temperature of the alternator, the power electronics and the test chamber. The unit controls either the quantity or the pressure of the cooling water.

Universal conditioning module

This universal conditioning module is ideal for a wide range of applications. The module is trolley mounted and includes a built-in stainless steel drip pan and a large compensation container. The module conditions cooling water to simulate the coolant conditions on a motor vehicle engine. The module accurately measures the flow rate, the system pressure and the temperature of the glycol-water coolant mixture as well as the physical characteristics (density and thermal capacity) of the fluid to be tempered and uses these measurements to calculate the instantaneous cooling/heating capacity. The test medium is separated in a primary and secondary circuit for the exchange of the coolant and for the adjustment of the flow. The compensation container is designed for a sufficient gas evolution before the fluid is sucked by the pump. In order to avoid boiling of the fluid, the pressure can be adjusted. The module can be controlled by a laptop computer or by a communication serial interface. All the analog signals can be recorded, stored, scaled and shown as graphic
displays. The system can also be used to take readings from other analog sensors, display the results as graphics and then calibrate the sensors. It is possible to program a series of conditioning plans for stand-alone operation and store them in a database. Conditioning plans are time-controlled and determine the pressure, flow rate and temperature setpoint values at preset intervals.

Test bench for milk-ducting element

The manual loading machine was designed to test the functionality of milk-ducting elements. The machine itself consists of two operations. The first one, OP10, traces the force and the way of the spring of each of the four chambers from the testing unit. Afterwards, the distance from the unit to the part, the preload force and the spring constant is calculated from the traced chart. After the unit has been put together, the second one, OP20, checks the flow of the unit with opened and closed chambers.

Manually Loaded Laser Welding Station

The manually loaded machine welds a screw nut connection of a hydraulic element using a solid-state laser. In an additional station a nondestructive 100 % test of the welding seam is done bringing a torque onto the hydraulic element. The final station sorts the welded part according to its state. 

Spindle assembly line

A historic component.
The hand spindle was replaced by the spinning wheel in the 15th century. This made it possible to spin a strong thread in a single action. In 1768 the spinning machine was invented. Today, modern, fully-automated textile machines use large numbers of spindles and it is therefore costeffective to assemble them automatically. 

Oil filling station for hydraulic solenoid valves

This machine is designed as a manually loaded station for filling solenoid valves with hydraulic transmission oil. After the manual insertion of the work piece by the operator, the parts are transported in the machine by a rotary table concept, constructed as a 90°-turn-lift-unit with removable work piece holders.
A 100% control of the filling grade is assured via two precision scales by which the mass of the work piece is measured before and after the filling procedure. Before filling the work piece is evacuated. During filling process the vacuum pressure and the oil flow are measured. Filling level, vacuum pressure, etc. will be evaluated according to adjusted test plan limits and a result file will be created.

Sonplas GmbH- Sachsenring 57 - D-94315 Straubing - Deutschland - Tel: +49 (0) 94 21 / 92 75 - 0 Fax: +49 (0) 94 21 / 92 75 199 - info(at)

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