Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
(OP)
Over the past 10 or 15 years various DIN standards for locking washers and similar hardware have been "withdrawn" and often not replaced.
Different entities ( mainly companies that sell specialty lockwashers ) generally make the claim that the various standards were withdrawn due to "ineffectiveness" at preventing loosening when subjected to dynamic and even static loads.
I do not dispute the questionable efficacy of split lockwashers, etc at actually preventing loosening.
But so far I have not seen any DIN documents saying why the various standards were withdrawn.
Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
Different entities ( mainly companies that sell specialty lockwashers ) generally make the claim that the various standards were withdrawn due to "ineffectiveness" at preventing loosening when subjected to dynamic and even static loads.
I do not dispute the questionable efficacy of split lockwashers, etc at actually preventing loosening.
But so far I have not seen any DIN documents saying why the various standards were withdrawn.
Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?





RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
for more of what you already know.
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
And in the ASME B18.2.1 it says:
NOTE: The word lock appearing in the names of products in this Standard is a generic term historically associated with their identification and is not intended to imply an indefinite permanency of fixity in attachments where the fasteners are used.
For lock washers see DIN 6796 and DIN 25201
Best regards
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
Regarding the Junkers tests, I think sliding a component back and forth a mm or so, with ball bearings in between the "clamped" bolted surfaces is not a particularly realistic test.
http://www.novatechloadcells.co.uk/eng/e036.htm
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
thread404-230741: Studies on the use of lock washers?
and the FAQ:
FAQ404-1257: Is a lock washer an effective torque retention device?
Dik
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
At my new job here, I have pointed out that helical spring lock washers are not regarded as locking devices. I have been informed that our screws are installed with calibrated power tools to known torques. Under vibration testing, done in-house, the fasteners with helical spring lock washers stay tight. The fasteners without lock washers tend to some loose.
They also use the small hex socket flat head and button head cap screws, that I detest. They have no problems stripping sockets. Production hates Phillips sockets. Again, everything is installed with controlled torque.
--
JHG
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
With regard to modeling the behavior of a joint subject to vibration, I'd say it about as close as you're going to get.
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
Are you responding to me? Most of the stuff here is sheet metal.
--
JHG
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
Mike Halloran
Pembroke Pines, FL, USA
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
http://1.bp.blogspot.com/_mGrjzceHfJM/TPo1cnpmp1I/...
http://1.bp.blogspot.com/-A7NRHWZFXIw/ULHQfBTOIkI/...
I guess somebody forgot to install the Nord-lock wshers for the photo shoot.
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
And 2... anyone who knows anything about fasteners will tell you that the first solution is always sufficient preload. If you apply enough preload, and maintain that preload in operation, fasteners don't come loose.
An assembly like a rod cap doesn't need additional locking because they are designed with careful attention to preload, and the components are stiff enough that preload relaxation isn't a problem.
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
RE: Has any body seen officially why DIN 127 etc lockwasher stds were withdrawn ?
1) If possible, a correctly designed and assembled bolted connection should not require additional securing elements to be functional.
2) An elastic / spring type securing element can only be functional within a bolted connection, if it is able to compensate the loss of clamping force due to embedding. For HT bolted connections (quality 8.8 and above), the washers as per DIN 127 etc. could not achieve this (only exception from the "old" range of options were washers as per DIN 6796). So, the different securing washers as e.g. of DIN 127 were withdrawn for general use but re-emitted for use in bolted connections of lower strength (below quality 8.8), pls. e. g. refer newer DIN 128. The tech. statement ~ #2) can be found in the comments.
Roland Heilmann
Lpz FRG