The Elsmar Cove Business Systems and Standards Discussion Forums Surface Roughness - What is difference between Ra, Rmax & Rt
 Forum User Name Keep Me Logged In Password
 Register Photo Albums Blogs FAQ Social Groups Calendar Search Today's Posts Mark Forums Read

 Elsmar Cove Forum Visitor Notice(s)

# Surface Roughness - What is difference between Ra, Rmax & Rt

 Elsmar XML RSS Feed Monitor the Elsmar Forum Sponsor Links Courtesy Quick Links Links that Cove visitors will find useful in your quest for knowledge: International Standards Bodies - World Wide Standards Bodies International Standards Organization - ISO Standards and Information Quality Digest
 Thread Tools Search this Thread Rating: Display Modes
Post Number #1
25th July 2007, 04:48 AM
 reddy Total Posts: 1
Surface Roughness - What is difference between Ra, Rmax & Rt

Can anybody help me in differentiating surface roughness measurment values in Ra,Rmax and Rt. In what conditions we use Rmax.

 Sponsored Links
Post Number #2
25th July 2007, 06:33 AM
 Ted Schmitt Total Posts: 668
Re: Surface Roughness - What is difference between Ra, Rmax & Rt

Quote:
 In Reply to Parent Post by reddy Can anybody help me in differentiating surface roughness measurment values in Ra,Rmax and Rt. In what conditions we use Rmax.
Welcome to the Cove !

Average roughness (Ra). The average height of the bumps on a surface, measured in micrometres or microinches.

Rt = is the difference between the highest peak and the lowest valley

Rmax = is the highest peak
 Thank You to Ted Schmitt for your informative Post and/or Attachment!
 Sponsored Links
Post Number #3
25th July 2007, 07:57 AM
 Stijloor Total Posts: 15,191
Re: Surface Roughness - What is difference between Ra, Rmax & Rt

Quote:
 In Reply to Parent Post by reddy Can anybody help me in differentiating surface roughness measurment values in Ra,Rmax and Rt. In what conditions we use Rmax.
Hello reddy,

Here is some info.

http://www.mfg.mtu.edu/cyberman/qual...ace.html#para2

Hope this helps.

Stijloor.
Post Number #4
25th July 2007, 08:22 AM
 AndyN Total Posts: 8,459
Re: Surface Roughness - What is difference between Ra, Rmax & Rt

Surface finish is often called out for two reasons:-

Functional performance, such as in a sealing ring application, bearing surfaces;

Appearance, where the finish has to look or feel smooth, etc. or requires further processing

It would be helpful to know how your organization is applying Ra to it's products.
Post Number #5
25th July 2007, 10:38 AM
 tenaiwa Total Posts: 20
Re: Surface Roughness - What is difference between Ra, Rmax & Rt

Hello,
It depends on your application
Pls consider also
function surface vs No function
friction->rolling or sliding
clearance fit or press fit
dimension presion of product
stress/load exist or not (corner,concave angle..)

hope it helps a little.
Post Number #6
25th July 2007, 10:58 AM
 harry Total Posts: 6,287
Re: Surface Roughness - What is difference between Ra, Rmax & Rt

Also have a look at here, here and here.

Last edited by harry; 25th July 2007 at 07:47 PM. Reason: fix link
Post Number #7
25th July 2007, 11:51 AM
 Stijloor Total Posts: 15,191
Re: Surface Roughness - What is difference between Ra, Rmax & Rt

Quote:
 In Reply to Parent Post by harry Also have a look at these threads.

Hello Harry,

Somehow, the link did not work.

Stijloor.
 Thanks to Stijloor for your informative Post and/or Attachment!

Lower Navigation Bar
 The Elsmar Cove Business Systems and Standards Discussion Forums Surface Roughness - What is difference between Ra, Rmax & Rt

 Bookmarks

 Visitors Currently Viewing this Thread: 1 (0 Registered Visitors (Members) and 1 Unregistered Guest Visitors)
 Thread Tools Search this Thread Search this Thread: Advanced Forum Search Display Modes Rate Thread Content Linear Mode Rate Thread Content: 5 : Excellent 4 : Good 3 : Average 2 : Bad 1 : Terrible

 Forum Posting Settings You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Emoticons are On [IMG] code is On HTML code is Off Forum Rules

 Similar Discussion Threads Discussion Thread Title Thread Starter Forum Replies Last Post or Poll Vote qcman General Measurement Device and Calibration Topics 3 16th January 2017 02:55 PM realsteeltools General Measurement Device and Calibration Topics 2 21st October 2013 02:30 PM Italian1022 Inspection, Prints (Drawings), Testing, Sampling and Related Topics 6 27th August 2009 08:05 AM schnuer Inspection, Prints (Drawings), Testing, Sampling and Related Topics 4 8th April 2008 05:39 PM ksanders Customer and Company Specific Requirements 5 3rd June 2004 09:57 PM

The time now is 11:43 AM. All times are GMT -4.
Your time zone can be changed in your UserCP --> Options.

 Contact Us - The Elsmar Cove Home Page - Privacy & DMCA/Copyright Information - Terms of Service - Top

 The Deming PDCA Cycle Implementing A Quality Management System FMEA Information APQP Information Auditing Information 8-D Problem Solving Statistics Error Proofing (Poka Yoke) Brainstorming Identifying Waste Pull Systems Lead Time Reduction Planned Maintenance Quick Setup Discovering Change Process Capability - Cp vs. Cpk Histogram Animation Process Loop Animation Taguchi Loss Function Fishbone / Cause and Effects Animation Cove Forum Sitemaps More Free Elsmar Files

NOTE: This forum uses "Cookies"