Sure. I’ll give you that “elevator rope gauge review” doesn’t sound like a fun blog entry. Even the word “extravaganza” isn’t going to make this the most exciting post. I’ve sat through half a dozen seminars on wire ropes put on by wire rope manufacturers and, well, I’d rather sit through another regenerative drive presentation. At least ThyssenKrupp gives us the K-Core rope that, when melted using sheave friction or cut with a pair of safety scissors, provides some fun images of chaos in the hoistway. But as inspectors, we use these little guys quite a bit and I wanted to give my review on the four gauges I have.
So why use a rope gauge? Well, after your visual inspection (of number of broken wires exceeding set limit within a certain distance, side by side broken wires across the crown, etc), there is still the possibility of internal breakage. A17.1 gives us a table of maximum reduced diameter values for common rope sizes. Rope gauges are the easiest way to measure this.
Now, I only carry one gauge as every jurisdiction I inspect has at least adopted A17.1 2000. There is, however, more than one set of rope retirement guidelines that the ASME A17.1 committee has come up with and, thus, more than one type of rope gauge. So let’s check them out. We’ll take A17.1 2007 and look at 22.214.171.124.3(cc)(1) which will tell us when we should retire suspension ropes. Since this is a gauge review, we are only interested in the maximum reduced diameter allowed which is ever so conveniently given to us in Table 126.96.36.199.3(cc)(3). Easy enough. However, if we look at 188.8.131.52.3(cc)(1)(d), we see an IF code. Due to fear of copyright infringement and brutal lashings and punishment by ASME, I’ll just paraphrase what this IF code is saying. IF the inspector sees bad conditions such as rouged ropes (corrosion), a lot of wear, not equal tension, etc. then the tolerance will be cut in half (50%)! The IF code is not found in earlier versions of A17.1 and the rope is retired exclusively based off of the published table regardless of rouge, etc. The earliest A17.1 I have in front of me is 1993 and the IF code can be found(through a little cross-reference table action) in 1993 under 1001.2(c) so the years that don’t require it are prior to 1993. Just a littlereminder that when adopting a new version of A17.1, most AHJ’s adopt the testing requirements of section 8 for all elevators, including existing. No grandfathering on this one.
So now for a short review of my four rope gauges. First, let’s start off with the Draka gauge. If you look closely, you will see that each groove is not a perfect U-groove. There are actually two diameter measurements for each rope size. A small ridge halfway in gives you that 50% less tolerance for the bad condition ropes. So, for instance, if you had a rouged rope, it better not fit even halfway into that groove. If there is no rouge and visually it is in good condition, the rope is allowed to stay if it fits into the first measurement. If the rope continues to fit into the u groove, it is undersized and should be retired.
Next, we have the purple Bethlehem gauge. This is obviously for measuring rope prior to that IF code we talked about earlier because the grooves are perfect U-grooves. Their website actually says it is a new model because the one previous was made from plastic. Good call on the upgrade, Beth. Perhaps you should go for another upgrade to include the ridges… you know, so it can be used in a non third-world country.
Quality Elevator Products makes the next gauge. This thing is looooong and they give a reason for it, too (on their website). “Gauge stays parallel to rope, so you are always checking from the top of one strand to the top of the opposite strand for maximum reduced diameter.” Neat. It’s still huge, you can only measure 4 rope sizes with it and, like the Bethlehem gauge, there is no ridge for the 50% tolerance measurement and is still sold this way… It doesn’t have U grooves like the others, instead opting for squares. It’s also fairly heavy, as would be expected by a solid, grenade-sized rope gauge.
Number four is the Wurtec gauge. I’m at a loss to explain its size and weight. Why? Why is this thing so heavy? Perhaps there was a need for a rope gauge/deadly weapon combo in the hoistway. Also, it’s huge. It takes almost twice the diameter to fit in the same grooves as the two other gauges that measure the same number of rope sizes. It does have the 50% tolerance ridge, which is good.
Draka, Wurtec, Bethlehem, Quality. In that order, that’s my ranking. The only reason Wurtec beats anything is because the other two are outdated.