Important points in choosing a thermowell
The thermowell should pay as much attention as it seems, considering the calculation of the Wake frequency, the choice of materials, etc. Installing a thermocouple near the top of the pump is not recommended unless you have an urgent need to do so.
Install the thermowell
(
Standards such as PIP PCSPS001 in section 4.6.5.1 indicate that heaters should not be located between the suction plates and inlets of pumps, compressors or turbines.) Install the thermowell on the elbow (safety margin for the following errors). But every recommendation must have a reason, the following are the factors
that affect the installation of this elbow near the upstream pump and so on.
Calculation of regeneration frequency according to ASME PTC 19.3 does not cover all cases.
Analysis of the thermowell response to fluid flow in ASME PTC 19.3 assumes a stable fluid velocity. Pulsed currents, in which the velocity of the fluid varies at a frequency close to the normal frequency of the thermowell, can also induce thermowell vibrations. Thermola failure has been attributed to exposure of a thermole to a pulsating fluid stream. (For example: other failures have been observed in installations near the centrifugal pump discharge.) So if we install a thermometer perpendicular to it and calculate the Wake frequency, we are still not sure that everything is an idea. Al works.
Does speed pay attention to you?
Sometimes speed is given to us to be questioned.
Speed changes due to the decelerator or blower added to a line in the last step can be lost. And note that changing the area affects the speed.
So the speed provided by the processing section may be higher for the line size and in the next steps, a reducer or blower is added. This affects the speed consideration and the process section must be informed to provide up-to-date speed considerations.
Miscellaneous errors
When building a bridge, this bridge is designed to withstand a weight far higher than it needs to be. This is done as a “safety margin” for unforeseen errors or factors that should be considered, such as abnormal weather considerations, etc., similarly when installed near an upstream pump or other location. Important If the thermola fails due to unpredictable conditions and breaks near such critical locations, this breakdown can be catastrophic. Like the pump has changed due to the need for higher capacity but the thermogel etc. has not changed. Therefore, for such unpredictable scenarios, it is better to reach the safety margin and install it in the elbow, which is much less likely to fail in the face of stress. Then evaluate the Thermowell case (even if mounted on one elbow) as a vertical case.