Tips & News - Jan. 2016

We also changed the mounting slot to a key-hole and added a separate mounting hole. This eliminated the need for a washer inside the clevis, thereby eliminating one part and reducing the number of things that could be dropped from a bucket. While these changes may seem minor, they took some work to implement. Utilities are standards driven. The larger cotter pin had to be special ordered andmade standard. “It’s not something we would typically have. It’s a lot longer than normal and it has a big loop that you can put your finger in easily,” says Wilson. Alliant Energy then purchased and installed thousands of the second version clevises. Counting both versions, we purchased and installed about 63,000 clevises. Version Three—Nov 2015: As Version Two was being installed, one of our line mechanics commented that it takes three hands to install the clevis -- one to hold the wire and two to install the spool insulator. This was inconvenient and time consuming, so we looked at ways to provide a separate hook that could be attached to the clevis temporarily. But, this added a part and made installation more complicated. Sometime later, another line mechanic suggested that we just push in part of the frame to make the hook to hold the neutral during installation and that is what we ended up doing. In April of 2015, Alliant Energy approved the third version and we think this will be the final one. The clevis has a finger of steel pushed inonone sideof the clevis that canbe used to temporarily hold the conductor while the spool insulator is installed. SATISFACTION It is true the redesigned clevis is somewhat more expensive than a standard neutral clevis, but Alliant Energy is confident the initial cost will be offset by reduced maintenance, like callouts due to neutral damage, and by the increased speed and ease of installation. It is important to not overlook the benefits during installation. Alliant Energy has over 40,000 miles of distribution lines and we replace 4,000 to 6,000 miles of per year. While we cannot use these clevises in every application, they are a big help the thousands of times we do install one. As for the cost of the design work, there was a time investment, but Alliant Energy did not pay HPS for their work or the 3D models. “The work was performed strictly for an increase in the sale of parts,” says Wilson. “Redesigning the neutral clevis was a fairly lengthy process, but it was satisfying. It is nice when you can help a customer who has a particular problem. Getting [3D] prints out to them,

gathering feedback, delivering a finished product, and having the customer be happy with the final design, is rewarding. Hubbell saw this as an opportunity to improve a product and meet customer needs,” points out Wilson. Further, while HPS began this project expecting to only sell the redesigned clevis to Alliant Energy, the appeal may be broader. “In the end, everyone saw how successful this project was and that the new clevis might be of interest to other utilities. We plan to bring the new design to the attention of other customers; they could have use for this as well,” Wilson points out. Alliant Energy is also pleased with the process. We have to give a lot of credit to the Hubbell representatives who took our suggestions back to the factory engineering departments. And, we have to credit the line mechanics in our company. They came to us when they had a problem and then offered valuable suggestions for an improvement. The best ideas came from Alliant Energy line crews, who work with these materials on a daily basis.

FIGURE 6 - Version 1: In the field, the new clevis mounts horizon- tally and one leg is offset so the upset pin is easy to install. The square washer keeps the head of the bolt from riding up into the corner of the bracket. The next design made it unnecessary.

FIGURE 7 - Version 2: Note the larger cotter pin. The around- the-corner, mounting slot has been replaced with a short slot on the side and a hole in the top. This eliminates the need for the washer inside the clevis on the mounting bolt.

FIGURE 8 - Prototype: The hook was designed to temporarily hold the neutral conductor during installation. It was later replaced in the design by the‘finger.’

HUBBELL POWER SYSTEMS |

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