Pressure transmitters and pressure gauges could be adapted to nearly every process condition using valves, protective devices and/or fittings. WIKA offers such combinations by means of a ?hook-up?, an application-specific and ready-to-install solution. It eliminates all the disadvantages that users experience with the choice to do the assembly themselves.
1. The logistical effort:
That is considerable. Measuring instruments, valves along with other accessories, if they are brought together in-house, usually should be sourced from different manufacturers, frequently from more than two companies. The order processes have to be coordinated, that may be time-consuming. Furthermore, supplier management requires additional resources.
2. Compatibility problems (risk of leakage):
Combinations of pressure measuring instruments with instrumentation valves and accessories aren’t standard solutions. Both elements of this assembly generally come, as mentioned, from different manufacturers. This increases the likelihood of complications during assembly.
The difference in these measuring arrangements with differential pressure gauges is obvious ? on the left, an example of an assembly made by the operator themselves, on the proper, the hook-up solution from WIKA.
A good example of this, shown here, is the mix of a differential pressure gauge with a valve manifold. The connection of the measuring instrument includes a different centre distance than that of the selected valve manifold (picture left). When this happens, the connection may be accomplished via an assembly with two pipe pieces and four adapters. But this solution increases the outlay with time and expense, as well as the risk of leakage, by doubling the sealing points (see arrow marks). Difficulties in assembly also arise if the tolerances of the connection interfaces from different suppliers do not match exactly. This carries the risk of leakage. In order to achieve the required compatibility, the qualification and delivery specification should be defined for each supplier with considerable effort.
ไดอะแฟรม of hook-up solutions:
Left: Pressure gauge with overpressure protector, a valve to split up the measuring instrument from the process and a siphon tube that protects the complete measuring arrangement from excessive temperatures.
Right: Pressure gauge with overpressure protector and monoflange (this permits separation of measuring instrument and process in the case of flange connections).
3. The installation effort:
On top of certain requirements for the procurement of suitable components, are the assembly costs for measuring points with instrumentation valves and accessories also added. These range from the development of special know-how and employee training to the provision of a suitable workplace, including tools and the necessary materials. Furthermore, an excellent control is mandatory to check on the functionality and reliability of the measuring arrangement, especially its leak tightness. That is especially important if, for example, it is just a process with critical gases.
Avoidance of risks
With a hook-up solution, users circumvent the efforts and potential risks described here. The measuring arrangement is assembled at WIKA (on the basis of the specified process parameters and the installation situation) from qualified individual parts and is tested for leaks. It is ready for installation in the process on delivery. If necessary, a measuring instrument can be combined with several instrumentation valves and accessories (see illustration left).
Note
Detailed info on valves and protective devices are available on the WIKA website.