Questions tagged [maintenance]
13 questions
13
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1 answer
Additional jacking force to overcome stiction/dry friction
It is common to lift bridges to replace bearings, etc.
In an ideal world the lifting capacity required of the jacks would be the self-weight of the bridge divided by the number of jacks (+ allowances for wind/snow, etc.).
From my (limited)…
thomasmichaelwallace
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2 answers
Summary of major outage management works needed in the 4th decade of a nuclear reactor?
I've noticed that quite a few commercial nuclear reactors have an extended outage (they close down for several months) some time late in their third decade, and the maintenance works during the closure involve significant investment. This cost has…
410 gone
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3
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How often do you need to check torques on bolted flanges?
Due to the fact that pipe flanges rely on bolts, and bolts rely on friction, it seems obvious to me, as a manufacturer of piping, to recommend that bolt torques need to be checked every so often, to ensure piping doesn't leak. I've got a few…
Mark
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2
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Is a motor failure caused by a defect bearing considered to be a failure mode or is it higher vibration and speed loss in FMEA/FMECA?
Let us assume we have a motor with a bearing which is exhibited to wear. Over time, we can observe higher vibration, increased noise and the motor speed reduces due to the bearing fault. In the end, the bearing fails and the motor is not able to…
user3352632
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2
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How to sample Mean-Time-To Failure values from a Weibull Distribution with shape 1.5?
I have a mean time to failure (MTTF) recorded from 100 systems which is 6.5 years. The shape parameter of my component is given with k = 1.3 (based on a list the from literature).
Now I want to sample (generate) further failure times based on a…
user3352632
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2
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3 answers
corrosion in electrical parts and wiring
I work in a pharmaceutical plant where saline solution is produced and bottled. The environment has to be clean (by pharma standards), which rules out many greases and other protective coatings.
As expected from a saline environment (from my…
PavoDive
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If you shut down a gas pipeline for a few months would you fill it with gas at full pressure?
This is of course inspired by the Nordstream gas pipelines in the Baltic Sea. When it was decided that Nordstream 2 would not start operating after construction finished they still filled it with natural gas at full pressure (a little above 100 bars…
quarague
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What does 1 x rpm or 2 x rpm or 3 x rpm in vibration analysis mean?
a description for virbation monitoring of industrial bearings states:
peak amplitues at 1 x rpm
should be an indicator for a fault in my case. Can somebody explain me what I have to understand under 1 x rpm. My chart (FFT) shows Amplitude in m/s^2…
user3352632
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1
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1 answer
Does anybody have information on how to refurbish an old laser rod (alexandrite or Nd Yag)? )
With usage, old laser rods eventually will need maintenance by cleaning and refurbishing it. Does anyone know how this is done?
baha hasan
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How to use B10 value of a component to predict its service life?
Recently I discovered that my reed-switch fails to function. According to the data sheet it has its service life, but it is expressed in B10.
If I search the definition of B10 itself: "B10 is a value used to estimate product lifetime. It provides a…
el-cheapo
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PVC Stripping issue on steel wire with pulley
I am having some issues with a PVC coated steel cable. The PVC often strips when used with a pulley.
I wanted to know why this may be happening and possible solutions for it.
Teyash Arjun
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Estimate Annual Maintenance Cost
Suppose, I am trying to install a completely new manufacturing plant, so I have no previous data to help me.
I want to calculate a rough estimate of my annual maintenance cost of machinery. Is there a way possible?
Note: We have purchased reused,…
Mayank Dhiman
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what is issue with my room brick wall? How can i solve it?
I have seen a sort disformation on wall of my room I have attached snapshot of both inside view(from inside room) and out side view(that is out of room)
inside view is below
out side view is below
engr
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