Virginia Department of Transportation
Bridge Cable Components
Turn-key Manufacturing, Steel Machining
Working with the Virginia Department of Transportation on infrastructure projects is always exciting to us! VDOT needed two bridge cable components for the Benjamin Harrison Memorial Bridge that had to be made from scratch.
Tektonics is a SWAM certified business registered in the eVA portal to do business with the State of Virginia. We are here to help with manufacturing and supplies of hardware and materials.
Good planning and communication, coupled with advanced manufacturing, and expert machinists are the foundation of our relationships with the engineers at VDOT.
Scheduling: Learning about the priorities of each project enables our team to prioritize our work and reduce delivery times. These fittings required several steps on one of our HAAS VF-2SS vertical mills, a trip to the Galvanizer, and some subsequent work to drill and tap a 7/8-14 hole for the rod ends in the assembly. We completed the second part in the order while the two-axis fittings were at the galvanizer.
Working from prints supplied by VDOT, our design team generated 3d modeled parts and produced shop drawing submittals (CAD). These 3d models are the basis for our programming in NX (CAM) by our team in the machine shop.
The first face of the rough steel blanks are machined with a 2-1/2” feed mill and a 3” face mill. Next, we use a 1-1/2” shoulder mill to remove material from the sides and ends of the blank. To mill the slot we used a 3/4” high feed mill to efficiently remove the interior material before finishing with a 12mm extended reach end mill. We incorporate chamfering the edges in the CNC program to remove any burrs. The blank is then flipped and the process repeats. After the sides and groove are machined the blank in turned side ways and a metal spacer is inserted into the groove to support the part in the next operation. The 3/4” high feed mill is used to rough mill the first hole and finished with a 1/2” end mill. The blank is flipped, and the hole in the second side is milled. After the part returns from the galvanizer we set up and add a threaded through hole to the end of the part using a center drill, tap drill, and tap.
Our process starts with a study on how to fixture and hold the part in each operation, how many tools will be required, and determining which of our machines is the right one for the job. Machines like our Haas VMCs allow up to 24 tools to be loaded at one time and the parts probe facilitate accurate repositioning of the parts during the machining process.
Benjamin Harrison Memorial Bridge
Our second part in the project was a 316 stainless angle bracket for supporting the Aerial Control Cables on the bridge. We used the same HAAS VF-2SS to drill and deburr the holes. We used an integrated probe cycle to measure and center the hole pattern on each web of the angle to ensure that everything would line up when assembled on site by VDOT.
At Tektonics we love working on jobs that utilize all of our strengths while creating parts that benefit local organizations.
We look forward to working with VDOT again in the future.