Piggybacking non-reinforced trailers

[Anonymous]

QUOTE: Originally posted by dgwicks

futuremodal:

This is properly a trucking forum question, but ...

Do you have the manufacturer and/or model name for the trailers with the integral front wheels and drawbar? I have never seen one. All of them that I have seen are a semi-trailer with a converter (what you call a dolly).

Also, I have heard many times about guys who can back up a set of doubles but I have never had the chance to actually see it done. It has always been a friend-of-a-friend, so I think it is an urban legend! What terminal is it that this "guy from CP" works at? I would take vacation to go watch that in operation!

dgwicks, on further thought I think you may be right, at least for the dry vans. It would make no sense to have an intergral second unit since there is no real tare weight savings or maintenance advantages over the kingpin/dolly setup. Trailer manufacturers would have to tweak the assembly line to accomodate integral trailers with kingpin trailers. And having the kingpin setup allows second trailers to be used as lead trailers. Only trailers such as hoppers and tankers are more suited to having the intergral drawbar units for second trailers.

[Anonymous]

QUOTE: Originally posted by dgwicks

futuremodal:

This is properly a trucking forum question, but ...

Do you have the manufacturer and/or model name for the trailers with the integral front wheels and drawbar? I have never seen one. All of them that I have seen are a semi-trailer with a converter (what you call a dolly).

Also, I have heard many times about guys who can back up a set of doubles but I have never had the chance to actually see it done. It has always been a friend-of-a-friend, so I think it is an urban legend! What terminal is it that this "guy from CP" works at? I would take vacation to go watch that in operation!

As to the first question, I don't have that information, but if I find the time I will look into it further. I am going by memory on that one. I did get a chance to examine a grain hopper trailer up close today and it is an integral unit. One can assume that other trailer types follow the same makeup.

As for the CP operation, it is from their "Expressway" service. The person who told me of this ability to back a complete double combo onto the platform cars was one of their salespeople. The reason I got involved with them was an idea I was trying to pitch them that involved loading the trailers "head first" by use of a parallel tractor unit. If you are interested, call or email one of their Expressway reps and aks them for yourself. You can get that information from the CP website.

[Anonymous]

futuremodal:

This is properly a trucking forum question, but ...

Do you have the manufacturer and/or model name for the trailers with the integral front wheels and drawbar? I have never seen one. All of them that I have seen are a semi-trailer with a converter (what you call a dolly).

Also, I have heard many times about guys who can back up a set of doubles but I have never had the chance to actually see it done. It has always been a friend-of-a-friend, so I think it is an urban legend! What terminal is it that this "guy from CP" works at? I would take vacation to go watch that in operation!

[DTomajko]

"Unreinforced" trailers are lifted everyday at intermodal ramps. In Pittsburgh, the sideloading packers are equipped with 12" x 36" shoes at the end of four arms for handling TOFC. There are no special sensors or devices used. The guards at top and bottom of the sides is really only there to prevent damaging the load-bearing top & bottom rails. I regularly lift Scheinder, Martrac, & various rental trailers without going near the lift points. It's dificult to get the shoes to fit in the very tight space over the tires.Some of UPS's newest 28' & 45' trailers don't even have siderail guards anymore. In five years on the ramp, I nor any of the other six packermen have broken a trailer. As far as lifting an air-ride trailer, I have never seen one that damaged the airbags when its wheels were lifted off the ground. The trailers I have worked on used limiting chains or the fully extended shock absorbers to limit maximum suspension travel. In a previous job we had an air bumper jack that would lift the rear of an empty trailer off the ground for working on all the tires or brakes at the same time. I never once damaged an airbag or any other component. Circus loading is a slow way to handle trailers. With overhead handling, the Lift Per Man Hour for TOFC can easily reach 12 per hour. If spotting chassis for COFC , stripping & spotting the track for reloading are added, then the LPMH quickly falls to four or less. A "reinforced" trailer isn't exempt from packer damage. A careless operator or improper load distribution can cause even TOFC trailers to fail,(there are presently four units awaiting final disposition in Pittsburgh that were removed from trains that had failed enroute).Good luck and stay safe.

[Overmod]

Keep in mind that 'ro-ro' (which to those readers unfamiliar with ship container handling stands for "roll-on roll-off") has a long and time-honored history in piggyback operation, being the principal way many of the original pig trains were loaded and unloaded. It was called 'circus-style' loading. One relic of this type of operation is the lowerable 5th wheels on some of the older TrailerTrain cars; these obviously had to fold down to clear the trailers being rolled off 'behind' them.

Note that this method required full decking the length of the train, at least where the wheels of the tractors and trailers rolled, and also ramps or aprons that would bridge the gaps between flatcars. This represented both additional tare weight and a higher center of gravity for the loaded trailers. Such issues were addressed with spine cars and 'pockets' for the trailer bogies, respectively, but this required the use of straddle cranes, Letroporters, etc. to place the trailers.

A big, and somewhat obvious, advantage for circus or ro-ro type loading and unloading is that no motorized equipment (aside from the tractors) is needed to perform the loading and unloading, meaning that only a couple of movable ramps would be needed to permit trailer access even in remote locations. I can see clear advantages to keeping doubles or triples 'complete' with their intermediate pups or dollies if the rail movement is intended as a 'bridge' for the complete 'road train' consist, for example through congested areas or past highway construction or areas where multiples are illegal or inadvisable.

[Anonymous]

QUOTE: Originally posted by corwinda

QUOTE: Originally posted by futuremodal
I guess now the only hurdle left is a way to lift the 2nd and 3rd trailers of a typical double and triple trailer combination. With respect to the B-train type trailer combo, which uses the kingpin/5th wheel connection for all trailers, I don't see how regular second and third trailers can be utilized with this new straddlecrane innovation and the typical spine cars or well cars with 5th wheel hitches. These trailers would need some kind of link and pin system to hook up to the trailer's drawbar, or a typically labor intensive lashing system to secure them to the flatcar's deck. I still think a ro-ro system is the only way to effectively piggyback these trailers.

If you're referring to the doubles/triples used by the LCL carriers; the 'trailer' you see consists of a trailer like the first with its kingpin in a one (or occasionally two) axle tow dolly that hitches to the back of the trailer in front. I routinely see those LCL trailers on TOFC cars.

I agree, some combo trailers especially LCL's do utilize a kingpin and a 5th wheel dolly, others have the front wheels and the drawbar as an integral part of the trailer itself. Since LCL's make up the majority of combo trailers, it may be that a lifting system that utilizes the kingpin and the slider rails attached to the rear trailer wheels is sufficient to cover most of those non-reinforced trailers. The only advantage that ro-ro would have over straddlecrane lifts for combo trailers is that the highway consist would not have to be broken up for ro-ro loading. I talked to a guy from CP a while back and the loading drivers for their ro-ro operation had somewhat perfected that art of backing such double combos onto the platfom cars. I don't know but I doubt they had tried that with any triple combos.......

[corwinda]

QUOTE: Originally posted by futuremodal
I guess now the only hurdle left is a way to lift the 2nd and 3rd trailers of a typical double and triple trailer combination. With respect to the B-train type trailer combo, which uses the kingpin/5th wheel connection for all trailers, I don't see how regular second and third trailers can be utilized with this new straddlecrane innovation and the typical spine cars or well cars with 5th wheel hitches. These trailers would need some kind of link and pin system to hook up to the trailer's drawbar, or a typically labor intensive lashing system to secure them to the flatcar's deck. I still think a ro-ro system is the only way to effectively piggyback these trailers.

If you're referring to the doubles/triples used by the LCL carriers; the 'trailer' you see consists of a trailer like the first with its kingpin in a one (or occasionally two) axle tow dolly that hitches to the back of the trailer in front. I routinely see those LCL trailers on TOFC cars.

[Anonymous]

QUOTE: Originally posted by Overmod

BNSF has indicated that their crane uses a combination of ultrasonic sensing and "redesigned lift components". They also worked with Arvin Meritor to design a means of lifting air-ride trailers without tearing the bags up -- I'm currently trying to find technical information on both these approaches. I believe some of these cranes are in service in south Memphis so I may be able to find out something more direct in a day or so.

Presumably all that's required is a better system of locating or distributing the lifting force. I can think of two approaches offhand:

1) Spreader with one side going to the bogie/suspension, or to the rails used by a sliding bogie, and the other side going to the kingpin area; this supports the trailer at the points it's designed to be supported in road service;

2) Web sling, with multiple padded slings under the trailer body. This is easier to make 'one-size-fits-all' but would be a bit more complex and labor-intensive to fit.

Having a set of sensors that would detect developing strains in the trailer body, and giving an operator or equipment the appropriate feedback signals to keep things aligned during the lift, swing, etc. goes a long way toward making TOFC with unreinforced trailers a workable proposition... It also neatly leverages technology in the name of lower effective tare weight.

I guess now the only hurdle left is a way to lift the 2nd and 3rd trailers of a typical double and triple trailer combination. With respect to the B-train type trailer combo, which uses the kingpin/5th wheel connection for all trailers, I don't see how regular second and third trailers can be utilized with this new straddlecrane innovation and the typical spine cars or well cars with 5th wheel hitches. These trailers would need some kind of link and pin system to hook up to the trailer's drawbar, or a typically labor intensive lashing system to secure them to the flatcar's deck. I still think a ro-ro system is the only way to effectively piggyback these trailers.

[ericsp]

QUOTE: Originally posted by Overmod

BNSF has indicated that their crane uses a combination of ultrasonic sensing and "redesigned lift components". They also worked with Arvin Meritor to design a means of lifting air-ride trailers without tearing the bags up -- I'm currently trying to find technical information on both these approaches. I believe some of these cranes are in service in south Memphis so I may be able to find out something more direct in a day or so.

Presumably all that's required is a better system of locating or distributing the lifting force. I can think of two approaches offhand:

1) Spreader with one side going to the bogie/suspension, or to the rails used by a sliding bogie, and the other side going to the kingpin area; this supports the trailer at the points it's designed to be supported in road service;

2) Web sling, with multiple padded slings under the trailer body. This is easier to make 'one-size-fits-all' but would be a bit more complex and labor-intensive to fit.

Having a set of sensors that would detect developing strains in the trailer body, and giving an operator or equipment the appropriate feedback signals to keep things aligned during the lift, swing, etc. goes a long way toward making TOFC with unreinforced trailers a workable proposition... It also neatly leverages technology in the name of lower effective tare weight.

Try going to http://www.uspto.gov/ I am sure they are probably patented.

[Overmod]

BNSF has indicated that their crane uses a combination of ultrasonic sensing and "redesigned lift components". They also worked with Arvin Meritor to design a means of lifting air-ride trailers without tearing the bags up -- I'm currently trying to find technical information on both these approaches. I believe some of these cranes are in service in south Memphis so I may be able to find out something more direct in a day or so.

Presumably all that's required is a better system of locating or distributing the lifting force. I can think of two approaches offhand:

1) Spreader with one side going to the bogie/suspension, or to the rails used by a sliding bogie, and the other side going to the kingpin area; this supports the trailer at the points it's designed to be supported in road service;

2) Web sling, with multiple padded slings under the trailer body. This is easier to make 'one-size-fits-all' but would be a bit more complex and labor-intensive to fit.

Having a set of sensors that would detect developing strains in the trailer body, and giving an operator or equipment the appropriate feedback signals to keep things aligned during the lift, swing, etc. goes a long way toward making TOFC with unreinforced trailers a workable proposition... It also neatly leverages technology in the name of lower effective tare weight.

[Anonymous]

A while back Mark made mention of an innovation by BNSF that allows straddlecranes to lift the non-reinforced trailers onto TOFC flats. Does anyone have any more detailed information on this?

Since the non-Z trailers make up over 70% of the truck trailers out there, it seems to me this is a potenial marketing bombshell that could have huge implications for increasing the railroads' share of intermodal traffic.