It is Not Always about Loose Contacts

by Ahmed Osman Mohamed Hamoudy
Electrical PM & PdM Engineer
Cemex, Egypt

In modern industries, there are many predictive maintenance techniques that can be utilized to avoid an unexpected failure. At CEMEX,  we count on those techniques and deploy them in such a way as to get the most use from it, and avoid any undesirable consequences. IR thermography's use has become widespread in cement plants; application areas typically include rotating kilns, insulation, mechanical, and electrical systems.

This article will explore the uses of IR thermography, specifically as part of the Motor Control Center systems predictive maintenance routine, including typical electrical panel failure points (contactor, terminations, feeding breaker, fuses, cables, etc...).

Figure 1. Rotary Kiln

One of the Clinker Rotary Kilns (4,500 Tons per Day) is supposed to be available for operation not less than a year, which is a challenge of course, to guarantee continuous operation for the kiln system for this time without any unexpected shutdown.

Stainless steel reflecting sky temp

This is extracted from a recent message board post:

"I'm curious as to how to adjust for stainless steel reflecting sky temp. The apparent reflected temp of the ground and surroundings is approx 50F. The bottom half of the drum is reflecting this (SP4). The top half is reflecting the sky (SP5). 

In my software, if I set the emissivity to 1, the sky temp in the picture shows -34F.
SP4 and SP5 *should* be the same temp, within a few degrees, based on the operation of the equipment. If I enter 50F as RAT for SP4, I have to enter -95F as RAT for SP5 to get the two temperatures to match.

Why is it -95F and not -34F for SP5? I want to make sure I'm understanding and looking at the image correctly. "

Click image to enlarge