October 27, 2000 Towers of High-Tech Strength

Volume 3 | Issue 7

PiRod Inc. designs and builds the towers and monopoles that connect today’s wireless communications networks.

Wireless communications devices are proliferating, and so are the structures used to transmit and send cellular, microwave and digital signals. In this industry, top-of-the-line custom antennas are designed and built by PiRod Inc., a 48-year-old company that has a reputation for high-quality products and impeccable service.

PiRod has engineered and manufactured thousands of towers standing across the United States and around the globe. These self-supporting towers, guyed towers and monopoles range in height from just 20 feet to more than 1,500 feet. Some hold one antenna, while others house scores of antennas, microwave dishes and cellular arrays. And although each structure is custom-designed to accommodate the load requirements and environmental needs of that installation, they all share a critical engineering component – PiRod’s commitment to quality, dependable performance and lasting value.

Growing with the Industry

PiRod came of age with the communications industry. The company was started in Plymouth, Ind., in the early 1950s, building towers for home television antennas. Towers for farms and business that used two-way radio for communication were added to the line in the mid-1950s. Then the focus of the business changed in the early 1970s, when sales of FM radio and UHF TV broadcast towers increased dramatically. The next change came in the mid-1980s, when demand for microwave communication towers and the rapid growth of the cellular communications market accelerated PiRod’s growth. Now, the company is a leading supplier of towers for cellular and PCS service, and for two-way, broadcast and microwave communications.

PiRod’s administrative and manufacturing facilities are located in four buildings on a 42-acre tract in Plymouth. Here, more than 250 employees are involved in designing and producing communications towers. The plant space occupies 185,500 square feet of space; outdoor storage space for towers and parts inventory spreads out over other areas of this property.

Committed to using technology to its advantage, PiRod’s facilities are connected by microwave and fiber-optic links that provide an integrated information and communications network. This system encompasses bookkeeping, inventory control, parts ordering and the efficient retrieval of inventory. State-of-the-art computerization is also used in the design and manufacturing processes.

Solid Products

PiRod’s stated objective is to produce premium products on time, and at a price that represents good value. To that end, the company manufactures only solid steel-rod, fully galvanized towers. In addition to its outstanding strength, solid steel has these advantages:

• Superior corrosion resistance: Unlike tubing, solid rod cannot corrode internally.
• Minimal surface area: Less surface area reduces wind resistance and ice accretion; the smaller structure members minimize the visual impact.
• Welded construction: Factory jig assembly produces precise fit and quick assembly.

PiRod builds on the premise that tower applications are so varied and complex that stock designs are never the best solution. Each PiRod tower is a custom order, so the company does not provide “standard” tower designs or keep an inventory of tower sections. However, the company’s catalogue offers a range of standard parts, mounts and accessories for almost every application and any brand of tower, so service or parts orders can usually be accommodated the same or the next day.

PiRod Chief Executive Officer Myron Noble says, “We’re able to achieve design and manufacturing excellence thanks to our skilled people. They use advanced computer technology and the most up-to-date manufacturing methods. They also care about doing the job right. The net result is a product that’s a solid value.”

Requests for proposals are usually handled within 24 hours, and include a tower drawing and normal soil foundation designs if requested. A proposal begins with a full structural analysis using proprietary CAD software. Data for the specific antenna loading and site conditions, plus any special requirements and anticipated needs, are included. This detailed proposal produces an accurate cost estimate, so there are no add-ons or adjustments later. In fact, the proposal is often accurate enough to require only an engineering review to complete the final analysis, and to start the final drawings and documentation required for permits.

PiRod’s staff engineers accomplish quick turnaround of sealed prints and calculations required for permits. Each tower comes with a foundation designed by experts specifically for the soil conditions at the site.

PiRod engineers also work with architects and specifiers to create functional, aesthetic tower designs. For example, a tower may be designed as a clock tower to fit into an architectural scheme. Or, a monopole may be constructed as a gold-tipped flagpole to meet zoning regulations. However, even the sleekest, most unobtrusive and elegant designs are engineered to handle tough wind, ice and load requirements.

Quality Inside and Outside

PiRod’s manufacturing processes for towers and monopoles are guided by the requirement that they be dependable long term, in every weather condition. To ensure that quality, all component parts, hardware and accessories are manufactured in-house using state-of-the-art technology, including computer-controlled “flame” cutting, programmable steel cutting, computer-controlled angle fabrication, CNC machining and robotic welding.

When it comes to purchasing materials for those components, PiRod’s policy is that all materials be supplied by vendors whose commitment to quality is equal to its own. The company has developed long-term relationships with its vendors to ensure those mutual quality standards are maintained.

An overview of PiRod’s manufacturing processes shows how the quality standards are applied at every step.

Construction of self-supporting and guyed towers sections:

• The mill scale is cleaned from the steel rods with a shot blaster.
  The steel rod is cut to required lengths.
• Rod used for cross members is bent to the correct shape and size.
• The rod components are welded using precision jigs to maintain close tolerances and perfect alignment. By design, the welds are significantly stronger than the steel rods they hold together.

Preparation of steel monopole sections:

• High-quality steel pipe is selected.
• Sections are cut to length.
• Patented flanges are added to the top and bottom of each section for precise, dependable connections.

Final assembly of sections:

• The tower is lined up by laying out the sections horizontally.
• Connecting sleeves are positioned, aligned and welded, resulting in easy assembly at the site, which keeps the project on schedule and holds costs down.
• Sections are hot-dipped galvanized for extra protection against the elements.
• Specially formulated, water-based, environmentally safe paint is applied.
• Finished products are moved to the outdoor storage area to await shipment.

Delivery is made by dedicated carriers in order to avoid delays. The structure arrives at the erection site ready for final assembly and erection. Here is where PiRod’s attention to quality pays off with an efficient, trouble-free process from the foundation to tower’s top – because, in PiRod’s view, “Up here, there’s no margin for error.”

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