How many pounds can a coupler withstand before breaking?

[BN U30C]

How many pounds can a coupler withstand before breaking?

[espeefoamer]

The answer,my friend,is blowin' in the wind[:)].

Sorry,I couldn't resist[}:)]!

[Anonymous]

I have seen 400,000 pounds thrown about in the trains threads these last few months.

[UPTRAIN]

Al's page could tell you: http://www.alkrug.vcn.com/rrfacts/drawbar.htm

[Anonymous]

I was told that the design strength of a Type E coupler on a dead pull was 350,000 pounds.

It could be plus or minus, depending on the age, wear and tear, etc. - probably mostly minus.

I've seen a guy with six old geeps and a heavy train open up (break) a knuckle just by mishandling the throttle - getting 'em too wide open too quickly.

Old Timer

[BaltACD]

QUOTE: Originally posted by Old Timer

I was told that the design strength of a Type E coupler on a dead pull was 350,000 pounds.

It could be plus or minus, depending on the age, wear and tear, etc. - probably mostly minus.

I've seen a guy with six old geeps and a heavy train open up (break) a knuckle just by mishandling the throttle - getting 'em too wide open too quickly.

Old Timer

Knuckles are mostly broken in one of two senarios....

1. Undesired emergency application of the brakes caused either by a 'kicker' (a faulty air brake valve that initiates the emergency when the engineer makes a routine 'service' application of the brakes). Once the U.D.E. occurs the engineer looses practical control of the slack in the train and the buff/draft slack action can overstress the knuckle causing it to break and shatter.

2. On a hard pull an engine can momentarily 'drop its load' thus causing unintended slack action to occur in the train which will overstress and break the knuckle.

Knuckles are not usually broken in sustained pulls as the tonnage rating of locomotives and local motive power practices will limit train size to the maximum stress that knuckles are designed for.

On one Eastern road Merchandise train tonnages are limited to the tonnage that 5 GP40's can handle on the territory. Solid Bulk Commodity Trains (Coal, Ore, Grain etc.) are limited to the tonnage rating of 4 SD40's(these trains normally have cars that are equipped with the High Strength knuckles). Rear end or mid-train Helper operation on the ruling grade can permit larger trains to operate as the ruling grade rarely occurs for the entire length of the crew district and if it does then the roads will generally use DP (Distributed Power).

[TH&B]

I've seen a cracked knuckle on a parked lift, is that something worth reporting or will the "system" take care of it? Obviousely it would break soon under stress, but I guess trains will get there walking inspection regularly.

ps; in case you think I'm wandering to close to railroad equipement but these tracks run through the street and a public park.