RTV ROPS - beware

[Diggin It]

I would not be surprised if the ROPS is designed for limited dynamic loading, meaning it could probably take a couple simple rolls, but if this RTV rolled 4+ times on the way to the bottom of a big hill, that is a lot of speed/energy building up. It's clear the lower frame bent too, and that tells us this wasn't a gentle flop. So it may have been beyond what the ROPS is meant to handle.

Yeah, I was trying to figure out how to word it. They may be designed to handle a single roll to the side on onto the top, or prevent a full roll. But once gravity takes over downhill, each roll would be more aggressive with more velocity. The force of the second or third roll while already in motion would be beyond design.

But the metal still seems awfully thin in what we can see in the pictures.

But hey, lets blame the manufacturer.

Nobody said that. We want them to see it to help them understand what's possible and maybe make changes.

 

[riptides]

Frame cracked too...I say all bets are off with the ROPS.

Yeah, I would send info to Kubota. You never know, they could engineer the heck out of a future ROPS and the accident you had may save someone else in the future.

 

[stevewarner1957]

Kubota should want to look at this failure. I look at the front passenger side post failure and wonder if the welding process didn't create a stress riser that caused the tubing to break clean at the level of the weld. The cracked frame appears to indicate the ROPS transferred the load to the frame as designed causing the fracture. Just my observations

 

[ruffdog]

In the end, the person didn't get hurt or killed so people can live and learn to see tomorrow.

 

[BleedingOrange]

A question for the OP. Is the vehicle insured ?

 

[PuffyC]

Seems Kubota did the bare minimum to meet some spec. That metal was so thin I wouldn't expect it to do much of anything.

 

[bdog]

It is insured against theft but not sure if the policy covers an accident or not.

A question for the OP. Is the vehicle insured ?

 

[ruffdog]

The kinetic energy of the 2000lb RTV going 10mph at the time of impact (while flipping) is over 9000 lbs.

(It only takes a free fall of 3.3ft to achieve a 10mph velocity.)

Depending on the actual speed and angle of hit(s) the ROPS took, it is not surprising the damage the RTV sustained.

The extent of the damage to the frame emphasizes the force induced into the structure.

 

[Little Red Tractor]

My classroom currently overlooks a construction project on campus. The rental telehandler they are using has the same type.

First, let me say I am sorry that happened and am glad no serious injury resulted. Hopefully, that will help us all be more careful. How old is the unit...was the steel pre or post covid? Structural integrity of a rops should be better...not like designed collapse on front end impacts. Yikes!

Warning, attepted humor follows; continue reading at your own risk. Using the reactionary approach, Kubota needs to be out of business. At the very least we need to require 30 hours of classroom training and licensure before allowing operation of these devices. Also, annual retraining. Before all of that we will need a committee to study it and confirm my solutions as vitally important. To prevent rollovers in the future we need to have out riggers attached to all off-road vehicles. Or would that be cultural appropriation? We'll form another committee to study that.

Love the humor--you surely must be, or have once been--a government worker; likely at policy-making level.

 

[6string]

They are not, really just a place to attach a roof.

I have seen Kawasaki‘s fold up like that too. The wall thickness on the tubing is closer to exhaust tubing than what is used for roll cages, made from DOM mild steel.

I have a 4010 Mule and you can tell the ROPS material is not very thick. As heavy as the 1140 is, one would assume(wrongly of course)that the ROPS to be made of thicker stuff.

 

[plowhog]

I wouldn’t really call it modified either. It had a sun shade canopy and the tweels both were added by the dealer at the time of purchase. Modified to me would be if we had a lift kit or welded something on to or drilled holes in the rops. We did not. The canopy was clamped on.

I realize there is no litigation future.

But ... if there was ... it would be considered modified.

I know the accident investigator for the incident below. Ford was invited to the post crash examination. Once a few minor modifications were found, the Ford reps said: "bye, we are done here."

One Killed When Ford GT Driven by Salma Hayek's Brother Slams Into Pickup

A Grammy Award-winning art director was killed when a Ford GT driven by the brother of actress Salma Hayek was involved in a crash with a pickup Sunday evening on Sunset Boulevard.

www.nbclosangeles.com

 

[Kschwennsen]

So from a engineering perspective (18.5 yrs in towing design) I'm looking at the tube material, the weld and the mounting and I would agree that the tube was way to thin for it to be labeled as ROP, the tube ripped at the weld as the weld was just buttered in (1/4" weld on 16Ga tube, come on man!) so there was a high heat affected zone which made the tube brittle. On the other hand seeing as the frame cracked, there must have been some wicked rolling action going on with it! It would have been fun to watch after the driver was ok.

With that said, the frame could be repaired and rewelded (by a certified frame welder) and possibly a new cage made for it. How much do you want for it, I'll come pick it up!

 

[mudking]

That is some thin looking steel….

I'll go ahead and take the flak for you. Kubota products are quality constructed, well supported, and enjoy a reputation for excellent longevity. They are also very well designed considering how lightweight the materials used are. The light weight is great for transport, if you trailer it often it can be a real plus. It also contributes to Kubota products being rollover-prone, and in the case of this UTV, it is also exposed in a ROPS that's too light for the job, this time. I'm not kicking this beehive because I enjoy a good slagging, it's just that someone has to say it.

 

[jdmeth]

I would suspect, that no ROPS is going to fair any better with multiple rolls going down hill.

So, how many times did it actually roll?

I bought a used John Deere 510 backhoe. The 20,000 lb piece of equipment had tumbled off a transport. There was asphalt in the top of the dipper arm. The ROPS was only shoved about a foot to the left.

I was working on a farm and looked across the field and saw four tires sticking up in the air. One of our drivers was mowing too close to a drainage canal and had rolled the 120 hp cab John Deere into it. One of my co-workers was a mechanical genius. He took some chains and two other tractors and less then an hour later they had it back to the barn. After washing it and tweaking the muffler back straight it was as good as new. The boss never knew.

I have a 1023E John Deere, I am confident the ROPS would protect me if I fell in ditch (no hills here).

 

[RancherGuy]

We rolled our 1120 today. Driver was not seriously hurt. He as thrown from vehicle which probably was best. The ROPS didn't fare too well. A buckled in passenger would be in bad shape.

I want to personally thank you for this post. Great discussion and some very thoughtful and keen observations and comments.

I also have a RTV-X1120D; 6 years old. I have taken apart the "ROPS" to thread electrical wire through it, so I am not at all surprised at the thickness. I am surprised that it not only bent, but broke. Tapping on it confirms the fact even without investigation.

My viewpoint is that indeed Kubota needs to investigate. I might be of the mindset to "exchange it" with a new unit at their expense so their engineers can study it. Swap the tires, of course.

This is enlightening. With a very slight cost, Kubota might consider stiffening the rear loop, behind the passengers, with a big "X" tube to at least keep that part supported, as well has upping the tubing thickness. Those are my ideas, anyway.

 

[Fielding]

1.4 The test requirements for ROPS are intended to provide protection for an operator wearing a seat belt under at least the following conditions: (a) a 360° roll about the machine longitudinal axis on a hard clay surface of a 30° maximum slope, at forward speeds up to 16 km/h, without losing contact with the slope; and (b) a 180° rear or frontal overturn on a hard, dry surface, without losing contact with the surface. Note: The testing of ROPS aims at minimizing the likelihood of operator injury resulting from accidental overturning during normal operation, although ROPS meeting the requirements of the ROPS/FOPS/OPS/TOPS series might not provide crush protection under all circumstances of machine overturn.

Guys look up the standards, they are public. ROPS are intended for a single low speed rollover. Not an indestructible crash pod.

 

[RickB]

There you go introducing facts.

 

[FTG-05]

OP, what's your plan to get this in front of Kubota corp? If you've already posted it, I missed it.

 

[MHarryE]

Fielding said it - there is a standard for ROPS. A ROPS is intended to absorb energy in a roll-over. I've witnessed a few ROPS certification tests, but ROPS on construction equipment, not off-highway utility vehicles. In our case, the frame is rigidly secured to a base and the ROPS is loaded using hydraulic cylinders in different directions. If the ROPS is too rigid, it can fail the test for not absorbing energy. Permanent deflection in a rollover is not unexpected. Remember cars & trucks are designed to absorb energy in a crash while protecting the occupant, but people still die in accidents. In my job, I would definitely be out to examine this. The fracture at the weld - may have been too many rollovers but I find it concerning. Bending the frame of the RTV that way - I think of my case if it was bending the frame of a D8 that way I could only envision it as an air drop in which the chutes didn't open.

 

[5030]

We rolled our 1120 today. Driver was not seriously hurt. He as thrown from vehicle which probably was best. The ROPS didn't fare too well. A buckled in passenger would be in bad shape.

Looks like a salvage yard queen too me. It's junk, frame is wonked.