Seiko & Citizen Watch Forum Message Archive
Great essay...and to expand...
I work in the elastomer industry - I thought the English names of the compounds might help readers understand that an L seal is not just a plain old O-ring...
Standard Seals:
NITRILE BUTADIENE (NBR) A copolymer of butediene and acrylonitrile, due to its excellent
resistance to petroleum products and wide temperature range, the most widely used elastomer in
the seal industry. Somewhat vulnerable to ozone, sunlight or weather.
Specific gravity.............................................1.0
Tensile strength..........................................4,000
Elongation, max..............................................4x
Hardness, Shore A......................................40-90
Brittle point (F)...............................................-40
L-Pack:
BUTYL RUBBER (IIR) A petroleum product made of co-polymerizingisobutylene and isoprene (for
desired degree necessary to vulcanization). Has excellent resistance to gas permeation, making it
useful for vacuum applications.
Specific gravity....................................0.92
Tensile strength...................................3,000
Elongation, max...................................3x
Hardness, Shore A................................40-80
Brittle point (F).....................................-80
Message Thread
- The Secret Inside Seiko Professional Diver Watches - Ryan - 2002-10-22 19:45:00
- Thanks Ryan, you done it again. Great article! - Chris Capra - 2002-10-22 20:22:00
- Outstanding!!!.........thanks! nt - pedro - 2002-10-22 20:24:00
- Great essay...and to expand... - Rob Backstrom - 2002-10-22 21:32:00
- WOW! Rob ... wish I would have talked with you before posting! - Ryan - 2002-10-22 21:57:00
- I've been looking for this information forever! Thanks Rob! nt - Duane Ruckle - 2002-10-23 03:44:00
- Larry, please add to FAQ! Awesome post again, Ryan! (nt) - Kevin Chan - 2002-10-22 21:39:00
- When I get a some time, I'm gonna make a Ryan article "section"...nt - Larry - 2002-10-22 22:46:00
- Hey Larry ... - Ryan - 2002-10-23 00:18:00
- h-e-double toothpicks! - Ryan - 2002-10-23 00:23:00
- Pass the Bourbon. *urp* - Carlos - 2002-10-23 05:24:00
- Do you have a list of your favorites? - Larry - 2002-10-23 06:23:00
- Larry, I'll email you soon. nt. - Ryan - 2002-10-23 20:19:00
- Man Ryan you always come up with something great. Thanks nt - Ken - 2002-10-22 22:26:00
- Where does the L gasket go in the watch? nt - Ken - 2002-10-22 22:36:00
- See the orange highlighted area here (scan) - Ryan - 2002-10-22 23:55:00
- thanks. nt - Ken - 2002-10-23 06:31:00
- Does Mr. Tokunaga always wear 2 watches? :-) nt - Ken - 2002-10-22 22:42:00
- Question ? - richie - 2002-10-23 01:30:00
- Incredible information. Thanks. Can someone tell me what the equation meant? - Yao - 2002-10-23 08:07:00
- Hi Yao, I am "webmaster" of Tokunaga's website. - Tacky - 2002-10-29 22:49:00
- Prospex 1000m. is now at the top (very top)of my list... - matt - 2002-10-23 11:02:00
- Here, this'll help out........ - Andy S. - 2002-10-23 11:42:00
- Aaarrrrrrrrraaahhhhh!! You fellows are supposed..... - matt - 2002-10-23 19:30:00
- Good read thx. nt - Andy S. - 2002-10-23 12:11:00
- Awsome! why are Japanese mags so much better??!! - RageRover - 2002-10-23 14:00:00
- Re: Japanese mags -- I read someone's comments over on the Rolex forum ... - Ryan - 2002-10-23 18:26:00