Archive for the ‘Photos’ Category

Aug-29-2008

Elevator hoist ropes (elevator cables)

Below is a photograph and magnified photograph of a set of elevator hoist ropes (commonly referred to as “cables”), and no; that’s not what they’re supposed to look like.  What you’re seeing is an accumulation of red rust deposits or “rouge” brought about by lack of lubrication (two top pointers) and metal flake under the driving sheave brought upon by premature wear of the sheave grooves (two bottom pointers).

While there isn’t a predominant amount of breaks in the actual rope lays themselves, this is a situation that demands immediate attention.  Because of the extreme lack of maintenance associated with elevator wire rope maintenance on this application, these hoist ropes will need to be replaced relatively soon — alot sooner than if they were properly maintained. In fact, university and technical studies (accepted calculations) have determined that failing to lubricate can reduce the life of hoist ropes by over 50%. Fifty percent.

With respect to the machine sheave, research studies have illustrated the adverse effect of even a 15% difference in rope tension on a typical elevator installation.  When the load factor for the highest tension rope is out of proportion, that particular rope will be impacted dramatically and wear quickly (in other words, when one rope is bearing most of the load instead of the tension being distributed equally).  Conversely, lower tension ropes may exhibit a sliding action through the sheave groove and prematurely wear the rope and the sheave (as seen above). To illustrate the point, think about your car’s tires.  How many miles will a tire last if it is severely under- or over-inflated? A rope running in sheaves subjected to an unequal load (tension) will give comparable results.

For reference, these ropes are original, but only 17 years old.

And finally, some reasons that ropes will prematurely wear are as follows:

  • Inadequate lubrication, or no lubrication at all.
  • Failure to periodically test rope tensions (required).
  • Increased (or increasing) car motion resistance – bad rollers or guides, etc.
  • Excessive car vibrations.
  • Obstructions making contact with ropes as the machine is running.
  • Volatile hoistway conditions (excessive humidity, dirt, sea air, rain, etc)
  • Improper shortening of ropes – twisting, tension imbalance, etc.

Have you seen your hoist ropes lately?  If you’re authorized to gain access to your building’s machine room, do yourself a favor and take a look.  Or…. call a consultant (shameless plug).

Posted under Information, Photos
Jun-9-2008

Running on empty (elevator machine and brake)

Below is a photo of a geared traction machine that has completely run out of gear oil, and worse; the gear oil leak has traveled over to the brake drum, soaking the brake pads.

All the red arrows point to places on the machine where gear oil is escaping. The problem here is two-fold. One, the machine is all but void of gear oil, causing the worm gear and ring gear to wear far more prematurely than expected. Two, the oil has traveled to the brake drum, and subsequently soaked the brake pads with oil. When our consultants visited this job, they instructed the building owner to place the elevator out of service.

Why? I’ll tell you why.

Suppose the elevator was running high speed in the down direction from the top floor (a 14 story building) and suddenly the power in the building was lost. One of two things can happen here…

The elevator machine would instantly apply the brake, but the chances of an oil soaked brake pad stopping a fully accelerated elevator are slim to none. Chances are, the elevator would continue to run through the brake, gain speed, and either (a) trip the governor overspeed thereby bringing the elevator to a violent halt, or (b) continue to run full speed onto the pit buffers causing an even more violent stop.

If you’re passenger in this elevator under either one of those conditions, the end result would be nothing short of disturbing. While there is a very slim chance that the elevator would stop normally, there was no reason for us to believe it would - or could.   So in the interest of public safety (our primary concern), we recommended the elevator be taken out of service, and a call to the elevator maintenance company be made immediately.

This was taken care of in short order, but the rest of the report took quite a bit longer.

Posted under Information, Photos
Apr-19-2008

Oily Elevator Pit

Above is a photograph of an elevator pit that rivals the Exxon Valdez spill. The problem here is two-fold.

One, the pit has not been properly sealed to prevent the intrusion of water, so below the 40 gallons of oil you see is another 80 gallons of water.

Two, the elevator jack seal (or packing) is leaking at an alarming rate. What you get is a film of oil on top of stagnating water. The result? You’d notice right away when you walk into the elevator (provided you don’t trip as it re-levels). It is, to say the least, a malodorous experience.

We’d like to tell you this is uncommon, but unfortunately its not. If you happen to notice an unpleasant odor as you walk into a hydraulic elevator, keep this picture in mind and immediately notify the building manager or owner.

Posted under Photos
Apr-2-2008

Hidden Dangers

The following is a photo of a typical elevator motor generator. Well, maybe not so typical. What you’re seeing is a generator brush that has a broken “shunt” (1), and another brush with solder on it’s shunt that had been thrown from the commutator due to overheating and poor commutation (2).

elevator generator

These are things that the average building owner/manager would never be aware of until the elevator (a high speed traction elevator) begins to mislevel. Had another brush shunt broken on this generator, it would have misleveled badly. Proper and diligent maintenance of generator and motor brushes are crucial to the safe operation of elevators. Brushes should be “seated” to provide proper commutation, and the commutator should be properly maintained and/or polished to provide a smooth surface for brushes to ride upon. This is not the case here.

Had this situation not been discovered, an accident due to trip and fall would have been eminent. Fortunately, the building owner had grown weary of all the resident complaints and hired our Consultant to investigate.

Posted under Photos
Mar-21-2008

That’s gonna leave a mark…

Above is a photograph of a typical elevator electrical door interlock assembly - minus the protection. The voltage running through the contacts in that switch is 230V. NORMALLY there is a cover over this switch to prevent accidental contact and to keep the contacts free of dust and dirt. Yes, this switch is accessible to anybody who lets curiosity get the better of them and reaches up to see what it is. And yes, contact with voltage that high can theoretically kill you.

Is a moral to the story really necessary here?

Posted under Photos
Mar-16-2008

Photo of the Day: “The Pits”

Above is the result of months - possibly years - of lack of preventative maintenance. A task as simple as cleaning out an elevator pit to prevent the accumulation of trash and to eliminate any potential fire hazard is apparently too time-consuming for the elevator service company’s route mechanic.

Posted under Photos