Keeping Energy Production in High Gear
Toothy round things drive the equipment that drives the energy industry, which helps make the world go around.
By Joel Neidig
Worldwide demand for energy is growing. Fortunately, so too is the technology for producing energy. This is where the gear—that humble mechanical cogwheel that quietly goes about its job of rotating and delivering torque to various pieces of machinery—has an important role to play.
That’s because a large portion of the world’s energy depends in one way or another upon gears: gears that can help drills bore through the earth’s crust and reach for oil or natural gas; gears that make mining for coal more effective; and gears that help wind turbines convert a breeze in the sky into electricity.
Indiana Technology and Manufacturing Companies (ITAMCO; Plymouth, IN) is one of the most extraordinary gear shops in the world, delivering precision-machined components to OEMs that serve the energy industry. In the process, ITAMCO helps a rapidly growing and industrializing world meet its energy needs.
The energy industry is still largely dominated by fossil fuels, and gears play a critical role in extracting three of its major players: oil, natural gas, and coal.
Drilling for Oil
ITAMCO’s gears are used in some of the nation’s leading top-drive drilling systems, which are primarily—though not exclusively—used on land-based oil wells. A top drive is a mechanical device on a drilling rig that provides clockwise torque to the drill to facilitate the process of drilling a borehole. The better the gear, the more reliable the torque that can be delivered by the top-drive system.
An advantage of a top drive is that it allows the drilling rig to drill longer sections of a stand of drill pipe. A rotary table type rig can only drill 30' (9-m) sections of drill pipe, while a top drive can drill 60–90' (18.3–27.4-m) stands, depending on the drilling rig type. Having longer sections of drill pipe allows the drilling rigs to drill deeper sections of the wellbore, thus making fewer connections of drill pipe—which reduces the amount of time it takes to reach the actual liquid gold underground.
Meanwhile, in sea-based quests for oil, we often see the jack-up rig: a self-elevating type of mobile platform that is capable of raising its hull over the surface of the sea. Jack-up rigs are used to search for oil and gas deposits down to a maximum water depth of 130 m.
The buoyant hull of the jack-up rig enables the unit and all attached machinery to be transported out to sea, to the desired location, by towboats. Here’s where the gears come into play. The platform, which can often weigh as much as 6000 tons (5444 t), stands on three legs that rest on the seabed and can be jacked up vertically. Much the way a car jack raises up a car one ratchet at a time, the rig is raised and lowered by up to 54 helical planetary gear units connected by racks and pinions.
Without this ability to “climb” up and down, sea-based oil exploration—which seldom takes place on smooth, placid waters—would be much more difficult.
Fracturing for Gas
In recent years, there’s been a lot of attention around hydraulic fracturing or fracking—the act of injecting highly pressurized liquid into rock to help release pockets of gas or oil. But what is the machinery behind this process?
In many cases, it’s a fracturing drive, which relies on spinning gears to deliver as much as 3000 hp (2237 kW) of pumping power. If that description reminds you a bit of an automobile engine, that’s no coincidence. Fracturing drive manufacturers are essentially bringing technology commonly found in high-performance automobiles and applying it to pressure pumping.
The gears in these drives matter because evenly spaced gear ratios provide smooth shifting for pumping. They also provide a much broader range of pumping speeds. A deep first gear ratio allows pumping at lower flow rates and pressure, giving greater flexibility.
Applying torque smoothly throughout the horsepower range optimizes productive horsepower and reduces stress on the entire powertrain. It also ensures that users have the appropriate amount of pressure to keep underground piping free of blockages—so that underground veins of gas can be explored more effectively.
Mining for Coal
If you’re trying to transport coal from a mine in a remote location to a power plant hundreds of miles away, chances are you’ll be using some type of heavy-haul surface mining truck. And that truck depends on a special type of gear known as an electric motor wheel planetary ring gear.
Having the right gears in the truck enables higher gradeability: the ability to climb up steep continuous grades, which reduces the amount of time required to get from point A to point B. It also makes getting down the hill easier by providing full retarding capability. This simply means that the truck can be fully stopped without applying the brake pedal, reducing brake wear and lengthening the intervals between brake servicing.
Once they’re off the hills and on to the roads, proper gears ensure that the trucks can obtain higher overall speeds—further increasing productivity, which reduces the overall cost per ton of sourcing and transporting coal.
Gears and Renewable Energy
Gears aren’t just used to harvest fossil fuels, of course. They also play a critical role in renewable energy sectors such as wind.
Wind turbines come in many different orientations—horizontal axis and vertical axis being the most common—but they all work on the same general principle. The energy in the wind turns two or three propeller-like blades around a rotor. The rotor is connected to the main shaft, which spins a generator to create electricity.
The gearbox is at the heart of any wind turbine. Having the right gears ensures excellent strength and torque capacity, surface durability and low noise performance as well as optimum bearing life under specified loads, thereby contributing to the gear unit’s long, trouble-free working life.
Building the Perfect Gear
Making such precise components for devices that serve the fossil fuel and renewable energy sectors requires a combination of sophisticated hardware and software.
The cornerstones of ITAMCO’s gear manufacturing facility are its gear grinders—giant machine tools for cutting the teeth of internal or external gears. Not only can these machines grind coarse pitch external gearing, but they can also grind internal helical gearing.
ITAMCO uses this hardware in conjunction with Autodesk Product Design Suite, a comprehensive solution delivering 3D design, simulation, collaboration, and visualization tools to help companies complete their entire engineering process. The Digital Prototyping capabilities of tools like Autodesk Inventor, which is part of Autodesk Product Design Suite, enable ITAMCO to create digital models of the gears first, before anything is physically manufactured.
The result? ITAMCO is able to manufacture gears to submicron tolerances. This precision is important because the more precisely manufactured a gear is, the better it will perform. A tighter tolerance and more accurate fit means less noise and vibration issues, which can cause other components to fail. Think of a wind turbine with loose, vibrating gears. It probably wouldn’t be very long before one of the blades came loose and tumbled to the ground.
Beyond producing less noise and vibration, a precisely manufactured gear will last longer. It won’t prematurely fail, and it will be able to handle more torque, more reliably, during its lifetime—all critical aspects for the machinery that is developed to serve the various sectors of the energy industry.
Gears don’t generate the same level of excitement and appreciation as, say, a shiny new smart phone with a built-in fingerprint scanner, but maybe they should.
There’s hardly a person on the planet that doesn’t directly or indirectly benefit from gears on a daily basis. Did you flip on a light switch or heat or cool your home today? The energy might have been harvested by gear-heavy equipment like wind turbines or oil rigs.
As long as the gears keep turning, the energy flows.
This article was first published in the 2014 edition of the Energy Manufacturing Yearbook.
Published Date : 6/16/2014