Air Brakes, Rules, Steam & other Technical Stuff

Brake Pipe Pressure Maintaining is probably the most valuable function of any modern day Automatic Brake Valve (ABV). It was available as far back as the first ABV designed to control air into and out of the Brake Pipe -- unfortunately, on all early day equipment, it only maintained the Brake Pipe against leakage when in the Release or Running positions.

Over the years, various schemes were employed by Locomotive Engineers to offset Brake Pipe leakage while a brake application was in effect. Some of these schemes were known as "bridge" braking or "hump" braking or "Feed Valve" braking -- the latter of which is still employed to this day for various reasons, even with modern pressure maintaining ABV's. Most all of these methods were "against the rules" (except for some rare railroads who actually had instructions for employing same in their AB&TH books). Yet Locomotive Engineers were able to employ these methods with great success time and time again until finally, the air brake manufacturer's began to work on Pressure Maintaining methods that would be safer to use. Even prior to the AB manufacturers' developing this equipment, some railroads began to find ways to modify their older brake equipment to have Pressure Maintaining.

I could find no information on these earlier conversions made by some railroads, so I had to do a bit of reinventing the wheel. While working on the Austin & Northwestern Railroad during the time I was furloughed from the AT&SF, it was about April of 1987 that I began coming up with various schemes for adding Pressure Maintaining to existing ABV's at a minimal cost. Most of the conversions were fairly simple, yielded excellent results and cost nearly nothing! I personally modified several of the A&NW locomotives with 24RL equipment and also a Texas & New Mexico Railroad locomotive with the same equipment. The Mount Rainier Scenic Railroad used one of my schemes utilizing a J-1 Relay valve on their 6-ET equipped locomotive with excellent results. If this subject is of interest, or you desire further information, just email me.

For technical information on air brakes in general and other information sources, check Wabco Technical Information. Any one with a keen interest in Air Brakes should belong to THE AIR BRAKE ASSOCIATION -- For more information about the organization and joining, click on this link: The Air Brake Association. This is a fine orgnaization that puts out some great technical papers and has an annual meeting in Chicago. I have been a member since 1976.

There have been several requests for some air brake information, such as, in particular, the No. 6-ET Locomotive and Tender Brake Equipment. I am contemplating adding some information to this site, but am asking for help in exactly what needs to be covered. Naturally, an abundance of material already exists in paper form specific to the various types of car and locomotive brake equipments and their operation, etc. If I add something to this site, I would like the information to be a little more unique and hard to find.

Now here's a piece of equipment that weighs a ton, works well and was overdesigned to last centuries! Unfortunately, it was shortly superceded by newer, lighter and more efficient equipment. Fortunately, this equipment stills lives on on a few cars not only in museums, but in everday operation on some excursion operations throughout the country. Being an ardent fan of this old equipment, I have been wanting to add some picture charts I developed for indentifying problems and working on the UC type passenger car equipment. I don't think that you will find anything else quite like them anywhere else.

These charts were a result of bootleg work I used to do on these valves for years. For some time, it was hard to find any air brake outfit that would work on this old and rare equipment, and then finally, when a concern or two did work on them, they wanted over $500 a set to just clean and lube them! Gaskets were also hard to come by, and I ended up have to rejuvenate the old rubber gaskets through long ago forgotten "witchdoctor" methods, or cut new ones by hand from sheet rubber. Anyway, for those interested, I present these charts and hope they prove to be interesting and useful. Even if you send your equipment out for cleaning and repair, the charts may still be useful in determining how good of a job was done by noting "blows" and problems before and after the work is done. Let me know what you think.

The ORIGINAL T&NO exams, with only slight additions and changes, are available now on the following links. I am happy to share this information, so please enjoy and let others know of their availability!

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