Vibration adjustment

March 14, 2020, 8:07 p.m.

Виброналадка, Вибродиагностика, Резонанс

The fight against vibration of fans is a special niche in the practice of vibration diagnostics. In many enterprises, fans turn a blind eye - they say cheap, low-liability, etc. But in my opinion, fans are the main source of experience for a beginner vibration diagnostics / vibration adjuster. Fans, as a rule, are mounted / operated in violation of the requirements, have low rigidity, and accordingly a huge mass of defects is manifested on them. In this article, we consider the effect of improper installation on the vibration of the unit, we localize the defect and eliminate it.

Image

VRAN type fan

Vibration diagnostics

March 8, 2020, 8:59 a.m.

Поводковый эффект муфты, Вибродиагностика

In this article I want to highlight a relatively rare defect, which is usually called the coupling leash effect. The problem is the uneven loading of fingers in the holes, which leads to an uneven load on the fingers during operation of the unit. As a result, a radial force appears, transmitted to the bearings, the vibration of which we measure. The defect is manifested the stronger, the more fingers in a row are incorrectly loaded (in other words, the more fingers do not participate in the operation of the coupling). Let's move on to a real practice example.

Image

Flexible sleeve coupling

Vibration diagnostics

March 7, 2020, 12:08 p.m.

Посторонний шум, Дефекты подшипников, Вибродиагностика

In this article, we consider a practical example of the diagnosis of extraneous noise from a pump D 2500-62-3 (N = 500 kW, n = 750 rpm) from the side of bearing No. 4. We identify the defect and determine the root cause of its formation.

Image

Pump D 2500-62-3

Ultrasound diagnostics

Feb. 29, 2020, 9:23 p.m.

Эксперимент, Дефекты подшипников, Ультразвук

More recently, an interesting case has occurred during maintenance of the electric motor of the pumping unit. Anyway for me. But it is interesting for the experiment and the consequences that will certainly replenish the piggy bank of my technical experience, and therefore yours. But first things first.

SDT-270

SDT-270 fully loaded

Ultrasound diagnostics

Feb. 29, 2020, 8:44 p.m.

Ультразвук, Дефекты подшипников

Friction is all around us. Without it we would find it very difficult to run, walk, or even stand on our own two feet. We need friction to drive our cars and fly our aeroplanes; and we need friction for our motors to drive pumps. But when it comes to our plant machinery, friction is both friend and foe.

Image

Over lubrication raises the temperature inside the bearing

Vibration adjustment

Feb. 29, 2020, 7:37 p.m.

Виброналадка, Дисбаланс, Резонанс

In this article I want to talk about the difficulties encountered during vibration adjustment, the interweaving of many different defects at the rotational speed, the search for solutions to the problem, and the possibilities of the vibration adjustment specialist are not unlimited. A story without a happy ending, as always from our own real practice.

ХП45/54-2,0

ХП45/54-2,0

Vibration diagnostics

Feb. 26, 2020, 7:42 p.m.

Электромагнитные дефекты, Вибродиагностика

Defects of electric motors of electromagnetic origin occupy a special niche in technical diagnostics, their identification is complicated, separate books are devoted to them. In this article I will share a recent case from my practice.

Electric motor

Vibration diagnostics

Feb. 25, 2020, 6:13 p.m.

Дефекты подшипников, Вибродиагностика

Another interesting example from practice. Two centrifugal fans of 3000 rpm are installed side by side, conventional air filters are at the inlets, the pressure pipe is common, the pressure pipes are rigidly connected to the cochlear flange. One is always at work, the second is in reserve. Switching once a month.

Fan circuit

Fan circuit with measuring points

Vibration diagnostics

Feb. 24, 2020, 2:59 p.m.

Вибродиагностика, Дефекты подшипников

And again the vibration diagnostics showed its effectiveness. Today is another example from the practice of detecting defects in bearings. We have a TsNA pump 100-50-5, engine power 22 kW, 3000 rpm. Vibrocontrol is carried out once a month. The vibration of the bearing support with the thrust bearings 46-309 installed in it usually did not exceed 2 mm / s. At the next vibration control, a colleague revealed an increase in vibration velocity to 4 mm / s, reported a possible bearing defect and recommended replenishment of the lubricant.

ЦНА 100-50-5

ЦНА 100-50-5

Vibration diagnostics

Feb. 23, 2020, 12:38 p.m.

Вибродиагностика, Дефекты подшипников

After almost a year of inactivity due to repair of valves on the pressure pipe, they called for the pump 1K100-65-250 to be turned on (N = 45 kW, n = 2940 rpm).

1К100-65-250

1К100-65-250
How to become an author?

Learn how to become an author and contribute to the techdiagnost.com community

LEARN

Powered by EVILEG, recommends hosting TimeWeb