Customer
Our client is a European manufacturer of products for sanitary fittings (tap heads, thermostatic cartridges, etc.).
Tested product
"zone valve" (zone valve / diverter valve)
The zone valve, also known as a diverter valve or "zone valve", is a plastic assembly with an electrothermal actuator. It is a specific valve useful for controlling the flow of water in hydronic (water) heating or cooling systems. Often consisting of several paths (2 to 3), they allow water to be redistributed to one or more selected areas of a building or living space.
Objective
Endurance testing of the zone valves in a cycle of heating (blowing hot air) and then cooling by forced air. The tests are performed on the heating elements present in the valve actuators.
Problematic issues
The bench consists of 20 modules that must be able to operate simultaneously and independently of each other.
Solution and result
The endurance bench built by the LF Technologies teams comprises a set of 20 stations that can test as many parts simultaneously. These stations are all mounted on a frame, which contains both a cold air loop (from 15°C to 25°C) and a hot air loop (from 25°C to 60°C). Fans ensure air circulation in the cabinets to homogenise the temperature. A hatch allows cold and warm air to be communicated between the boxes and the modules. Within a module, the air circulates around the actuator and then back into the main chamber.
The valve zones to be tested are connected to terminal blocks (on the modules) which supply them with power according to the selected programme and the set endurance cycle phases.
Each module is equipped with a displacement sensor, in order to measure the position of the sensitive element. In addition, the modules are also equipped with an input/output interface block that communicates via a network with the control PC. This technology has the advantage of interfacing a large number of sensors/actuators with simple connectivity, as well as the ability to easily add inputs and outputs in the future.
Each of the stations is supplied with tooling to position the test piece in the air stream, providing several functions such as displacement measurement, quick change of a stress spring or spring preload adjustment.
In order to guarantee the safety of the operators, the bench is equipped with 3 emergency stops allowing the de-energization of the active parts (hatches, cooling unit, fan, heating resistors and electrical supply of the sensitive elements).
