Greasing Bearings - How Much is Enough?Written by Thomas Yoon
Previously, we have talked about using suitable greases for different applications. Basically, we want to use low temperature greases for low temperature applications and high temperature greases for high temperature applications. The reason is quite simple - we want grease to form a thin film of lubricating oil between rubbing surfaces. If we use high temperature grease for normal temperature applications, chances are grease will still be in semi-solid state and will not flow to cover contact surfaces of moving components during operating conditions. Assuming you have chosen correct grease, how do you determine how much you need to put into bearing? Excessive grease lubrication can easily cause overheating. The grease gets churned around within moving parts of bearing and has nowhere to go. The temperature rises. The grease becomes wrong temperature selection even though application is correct. A general rule to follow is that bearing should be filled completely but free space in housing only partially. This gives room for grease to be ejected from bearing on start-up. However, there is some grease, so-called "totally-filled" greases like lithium soap greases that can allow filling up to 90% of free space in housing, without risk of a temperature rise. This is because they are special. Their stability at high temperatures is excellent and can be utilized over a wider temperature range than sodium soap greases.
| | Which w3wp.exe process belongs to which App Pool in IIS6 Written by Scott Forsyth
Along with Windows Server 2003 and Internet Information Services 6.0 came a large number of benefits. For us IIS admins, it was a great welcome set of changes. But, one apparent difficultly is matching up w3wp.exe processes displayed in Task Manager to Application Pools in IIS.Review of IIS5 In IIS5.0 (Windows 2000 Server), each site that is set to Out Of Process will spin up a new instance of dllhost.exe. Windows Task Manager lists them. Now, trick is to find out which dllhost.exe matches which site. My favorite way is to use Component Services. To do so, open Component Services from Administrative Tools, drill down to Computers -> My Computer and select COM+ Applications. Now select View from top menu and select Status. Beside each site that currently has a dllhost.exe process spun up is Process ID (PID). Using Task Manager, you can tell memory and CPU. Note: If Process ID doesn't display for you in Task Manager, select View -> Select Columns and add it. What about IIS6? But, that doesn't work anymore with IIS6.0. Now each site in IIS6 is placed in an Application Pool. Each Application Pool is completely separated from other App Pools by running in its own process called w3wp.exe. This make life SO much easier. Now, trick is to match up process shown in Task Manager with Application Pool set up in IIS. If there is a different user for each application pool, Windows Task Manager is easiest way to find out which application pool belongs to which site since Task Manager will display user process runs as.
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