J.B.Bane Wrote:
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> I can't immediately address the difference to an L
> triple, but as Brian said above a k1 and k2 are
> functionally the same in principal of operation.
> A K2 is designed with bigger ports to correspond
> with supplying air to bigger brake cylinders that
> would be found on std. ga. freight cars. I have
> seen K1's on several std. ga. cabooses with 8"
> brake cylinders, but in general I think K1's are
> going to be found on NG equipment with 6 and 8
> inch brake cylinders and k2's for 10" brake
> cylinders common to std. ga. cars. They are not
> readily interchanged thanks to the k1 mounting
> with 2 bolts and the k2 with 3. H triples can be
> thought of as the interchangeable predecessor to
> the K triple so the H1 and H2 interchange with K1
> and K2 respectively. The H has a narrower slide
> valve and lacks the retarded relaease feature
> added to the K. They were often sent to WABCO and
> factory converted to the functionality of a K. A
> K or converted H has a wing on the top to
> distinguish them apart from an unconverted H at a
> glance. The converted Hs have the wing attached
> with a screw, while the wing is part of the K
> casting. Another very similar variant is the P
> triple.. Correct me on this someone if I am
> wrong. We have one car at SVRR with an H1 that I
> rebuilt years back which is on our "Leviathan"
> which is a small std. ga. business car running on
> NG trucks. It has a 10" brake cylinder. The
> slide valve is narrower than a K1 triple and
> probably the same as an H1, but with noticeably
> bigger ports. I had a machine shop make me a
> lapping tool for the K1 and H1's. One way it is
> the right width for the K1 seat and turned 90deg.
> the other way narrower for the H1's. As I recall
> the narrow side worked correctly on the P1 I dealt
> with. I had good success with between 15 and 20
> triple valve rebuilds at SVRR years back some of
> which were made up of parts from several to make
> one. The 2 or 3 failures I had were all due to
> lack of patience in lapping. This can not be
> stressed too much.
I missed the part about "L" valves...
"L" triple valves are for passenger use. They were the first valve to employ a "graduated release" of the air brakes. Before this, you could graduate the application to get more braking effort, but to reduce the braking effort, you had to completely release the brakes and re-apply them. The "L" triple allowed you to graduate the brakes off if desired. In addition to the L valve, auxiliary res, and brake cylinder, there is a "supplemental reservoir" used to partially recharge the auxiliary res, when the brakes are graduated off.
There has been only one "L" valve in Chama (and probably the entire narrow gauge). It was on the infamous Hinman car from Mexico.
