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 alternative of doing the assembly themselves.
1. The logistical effort:
This 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 need to be coordinated, which is often time-consuming. Furthermore, supplier management requires additional resources.
2. Compatibility problems (threat of leakage):
Combinations of pressure measuring instruments with instrumentation valves and accessories aren’t standard solutions. Both components of such an assembly generally come, as mentioned, from different manufacturers. This increases the probability of complications during assembly.
The difference in these measuring arrangements with differential pressure gauges is obvious ? on the left, a good example of an assembly created by the operator themselves, on the right, 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 bond of the measuring instrument has a different centre distance than that of the selected valve manifold (picture left). In such a case, the connection can be achieved via an assembly with two pipe pieces and four adapters. But this solution increases the outlay in time and expense, plus the threat of leakage, by doubling the sealing points (see arrow marks). Difficulties in assembly also arise if the tolerances of the bond interfaces from different suppliers usually do not match exactly. This carries the risk of leakage. In order to achieve the desired compatibility, the qualification and delivery specification should be defined for every supplier with considerable effort.
Two types of hook-up solutions:
Left: Pressure gauge with overpressure protector, a valve to separate the measuring instrument from the process and a siphon tube that protects the entire measuring arrangement from excessive temperatures.
Right: Pressure gauge with overpressure protector and monoflange (this enables separation of measuring instrument and process regarding 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 add the development of special know-how and employee training to the provision of a suitable workplace, including tools and the required materials. Furthermore, a quality control is mandatory to check the functionality and reliability of the measuring arrangement, especially its leak tightness. This is especially important if, for example, it is 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 (based on the specified process parameters and the installation situation) from qualified individual parts and is tested for leaks. It really is ready for installation along the way on delivery. If necessary, a measuring instrument can also be combined with several instrumentation valves and accessories (see illustration left).
Note
Detailed ไดอะแฟรม ซีล on valves and protective devices are available on the WIKA website.