Maintenance That’s Not Boring
Keeping Up on Auger Boring Maintenance
By Jason Morgan
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| Because auger boring machines cut through all kinds of muck, it’s important to thoroughly wash the machine and keep it in dry storage after the job is done. |
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An auger boring machine is a precise tunneling tool. To keep your boring operations clean cut, you have to keep your auger boring machine in tip top shape — and that goes beyond greasing, lubing and keeping it clean.
“The drive clutch/pressure plate assembly is the most common component to fail on any auger boring machine,” says Aaron Veidmark, Owner/Equipment and Property Manager for SSC Boring. “The operator will notice a range of indications that a clutch/pressure plate has failed, including the input shaft and gearbox not turning with the engine running and transmission in gear, an audible grinding or metal to metal noise coming from the bell housing area and/or an unusual vibration in the clutch handle. The only solution to this scenario is to remove the broken clutch assembly and replace it with a new one.”
Not all hiccups in auger boring are as painful as a failed clutch/pressure plate. More commonly, you’re likely to snag the cutting head on a seam of rock in your cutting path, according to Tony Barbera, Vice President of Barbco Inc. There are typically several possible outcomes in this instance, one is that it momentarily stalls the drive train. Or, a large rock makes its way down through the auger string and into the spoil ejector chamber. It’s also possible that rock could get caught between the paddles and the top of the spoil shoot; again, stalling the drive shaft.
“If the operator’s quick, he can anticipate the event,” says Barbera. “He can pull the clutch in to unload the momentum before the input shaft to the gearbox breaks. However, when the cutting head snags, windup could occur in the auger string. When the clutch is unloaded, it allows the auger string to relax — backspining through the transmition and blowing your clutch out. These are very common situations that every operator will experience. I recommend keeping one or two spare input shafts and clutch assemblies on hand.”
If you spend enough of your time drilling through dirt, these situations are almost unavoidable, but you can safeguard yourself against unnecessary downtime by paying attention to your recommended maintenance schedule — both daily and long term.
Before starting the machine, it’s a good idea to grease all the locations specified in the operator’s manual and visually inspect all of the fluid levels, adding where it’s needed. It’s not a bad idea to make sure that all the bolts from the engine mount to the spoil ejector are tight.
After that, fire up the auger and run through the gears — testing every function, incuding the emergency kill switch, hydraulic valve and cylinder operation and ensuring that your clutch is operating properly.
Long-term maintenance will be detailed in the operator’s manual, but will likely include a more thorough check of fluids to make sure there’s no foam in the oil (if there is, drain and replace), checking bolts for proper torque, the front drive for wear and opening the bell housing cover to check that the throw-out bearing moves freely by engaging and releasing the clutch to make sure the throw-out does not continue to spin, according to Michael W. Albers, Owner of Bor-It Mfg. Co. Inc.
A particular area of concern on the auger boring machine is the cutting head. This is likely to see the most wear during operation and should be watched closely. Normally, an increase in pressure and torque requirements is a good indicator that the head is not cutting properly. Remove the auger and head and check for uneven wear, says Albers.
“All cutters can be replaced, but you may have to torch them off and weld on new ones,” says Barbera. “Some [cutting heads] have receivers that get welded down, and the cutting bits are retained by spring clips, roll pins or bolts. Some cutters are made to spin during use like bullet bits and are designed to self sharpen. Other examples of cutting bits are ones that spin such as roller cone bits or disk cutters. Damage occurs when they stop spinning, allowing them to develop flat spots that require replacement.”
Backhoe teeth are normally held on with roll pins. Simply remove the pin to replace the cutter. Bullet bits can be knocked out from the back. Bullet bit manufactures also make a tool to remove the bit. And while most disc cutters unbolt, many cutting bits need welded down.
By keeping up with your daily and long-term maintenance, you can ensure that your auger boring machine serves you well for years to come.
Jason Morgan is Associate Editor of Utility Contractor.
Guided AXIS Is a Borer’s Ally
Detailing Vermeer’s Revolutionary Boring System
By Kelly Moore
Among the examples of robust trenchless technologies hitting the global underground construction market, Vermeer’s AXIS guided boring system is an example of customization-focused trenchless equipment. The AXIS guided boring system is a pit-launched, laser-guided system that can achieve pinpoint, on-grade accuracy when installing water and sewer lines, and its versatile design allows for multiple applications in the installation of new sewer and water lines.
The AXIS guided boring system is composed of four main components: power unit, rack, vacuum pump and storage tank.
The power unit contains the engine and hydraulic pumps and connects to the rack, which includes the thrust/pullback carriage assembly and gearbox. As the thrust/pullback carriage assembly moves up the rack, the gearbox simultaneously provides rotation to the cutter bit at the front of the drill head.
As the drill stem cuts its way through the soil, the displaced material is removed by a high-power vacuum system that diverts spoil to a storage tank.
How It Works
After excavating the launch and exit pits, crews set the AXIS system’s pipe laser in the launch pit at the grade and depth the project dictates. Next, the leveling frame is set, and the rack assembly is positioned in the launch pit.
The drill head — complete with an on-board camera connected to a control station display — must be positioned next. While the cutter bit rotates through the soil, the operator monitors the target grade, making adjustments as necessary. Displaced soil is vacuumed out through the drill stem to the storage tank.
After the drill head is bored in, the operator uncouples it from the carriage assembly, which retracts to its most rear position in preparation for the first drill stem.
Crews attach the drill stem to the rear portion of the drill head, and the carriage assembly thrusts the stem through the hole, repeating the process with as many drill stems as necessary to reach the exit pit.
Depending on the type of pipe required for the job, operators will use one of two installation methods, pipe-jacking for rigid-constructed pipe or the AXIS system’s exclusive pull-back installation method.
With the pull-back method, the drill head is removed from the exit pit and replaced by a section of product pipe. When the carriage assembly retracts, it pulls the drill stem and the product pipe back through the bore. Once fully retracted, crews uncouple the drill stem and hoist it out of the launch pit. The carriage returns to its most forward position, couples with the next section of drill stem and repeats the process, pulling towards the launch pit until all drill stem has been removed and product pipe lines the bore.
Because of the flexibility of the four major AXIS system components, various set-up configurations can be used to adjust the machine’s footprint based on jobsite and transport characteristics. For instance, on a dense, urban jobsite, the AXIS system can be set up in one lane of traffic.
Designed to install a variety of pipe materials, the AXIS system is capable of handling diameters ranging from 10 to 14 in. Not only is the ability to scale for size important; it’s essential for contractors to be able to switch between types of pipe as market conditions and material costs fluctuate. The AXIS system can install clay, steel, PE and PVC pipe.
Kelly Moore is a Technical Writer for Two Rivers Marketing, based in Des Moines, Iowa.
Granting an Extention
Stretching the Life of your HDD System
By Richard Levings
 Isn’t it amazing how the ebb and flow of economic cycles can come and go so quickly? Many contractors have experienced the boom of the past several years and have been able to replace their construction equipment on a regular cycle. Unfortunately, when we hit the lower curve of a cycle, it became more difficult to stay on schedule with equipment replacement. So how does a contractor make his or her equipment last through the bottom of the economic cycle without replacing it? Here are some simple ways to stretch your equipment investment dollars to get the most production out of your operation.
Philosophy — Develop a company philosophy promoting maintenance as a high priority. Some companies trade their equipment on regular cycles and tend not to be as focused on a strict maintenance policy as those companies that have a longer operation policy. This philosophy must be communicated and adopted throughout the entire company to make it work.
Maintenance Plan — Develop a scheduled maintenance plan and do your very best to follow it. Regularly scheduled maintenance does not include emergency breakdowns, but rather the recommended service items that are typically identified by the manufacturer and assigned hour limits to measure service and replacement intervals. By following these schedules, you will decrease your downtime in the field and help ensure the maximum life out of the entire system.
Trained Service Personnel — While it is advantageous to use factory trained service personnel in local equipment dealerships, it is not always a practical possibility. Identify your internal service technicians and have them trained by your local dealer. HDD systems are not rocket science, but they are specialized construction equipment. Having and utilizing trained personnel and appropriate service manuals will help ensure your equipment is serviced correctly and running smoothly.
Parts Inventory Plan — Many companies are not located near a construction equipment dealer. This frequently increases downtime due to the availability of repair or replacement parts. Having your own inventory of parts may seem like a large investment, but in the end, it will pay big dividends. Most people do not consider the amount of time it takes or the mileage they have to drive to pick up emergency parts when equipment is down. Putting a price on labor, mileage and lost revenue will help you see how an inventory of parts will reduce your overall cost. It also allows you to stay on time with your regularly scheduled maintenance because you always have the parts on hand when the maintenance is scheduled.
Immediate Repairs — The drill unit is the focal point of most HDD systems. The drill is the most complex and expensive component of the system and typically experiences the most wear. There are a few basic areas users should pay attention to. However, it should be noted this is not an all-inclusive list. Please refer to your operator’s manuals and service manuals for a complete list of maintenance items.
Drill Frame — Examine the carriage frame and rollers, wrench jaw inserts and cylinders, saver sub (drive chuck), pipe guides or rollers, rack and pinion or chain and sprockets on the thrust system, pipeloader shuttles and grippers and fluid swivel.
Power Unit — Check the engine oil and filters, engine cooling system, air filtration system, hydraulic oil and filters, hydraulic cooler, hydraulic hoses and fittings, periodic hydraulic pressure checks to evaluate relief settings and pump/motor wear, electrical harnesses and couplings for wear and abrasion due to interference with other components, all guards and cowlings to maintain proper air flows.
Fluid Pump — Inspect all liners/packing, valves, seats and shut-off valves, and double check the antifreeze system for cold weather applications.
Undercarriage — Check tracks for wear and ensure proper tension. Check the hydraulic drive motor or gearboxes for any wear or damage.
Drill Pipe and Downhole Tools — Check the drill pipe body for wear and straightness and tool joint wear and damage. Be sure to rotate the drill pipe in the pipe box for even wear, while checking the beacon housing and beacon lids, nozzles, beacon buddy, threaded connections and drill bit bolts. Take notice of if drill bit wear for is still efficient penetration rates, and that hole opener cutters and fluid orifices aren’t obstructed. The fluid mixing system is an often overlooked component of an HDD system. It is integral as it provides the lifeblood to the system.
Fluid Mixing Pump — Inspect seals, connections and drive coupling. Test the drain system for cold weather applications.
Engine — Inspect oil levels, air breather, rope or electric start system.
Valves and Hoses — Exercise valve handles and be sure to check fittings and hoses for leaks. It’s also a good idea to drain them in cold weather.
Venturi — Clean mixing hopper and mixing system to keep the fluid path clear of any obstructions.
Tank — Clean regularly, check mixing jets and drain in cold weather. The electronic guidance system completes the HDD system.
Tracker — Keep clean and store in a dry area and keep a supply of fresh batteries or a fully-charged rechargeable battery. Do not place the tracker in an area where it can be run over by other equipment.
Beacon (Sonde) — Remove from the beacon housing each day, clean and store in the carrying case, use fresh batteries and test before each bore.
Remote Display — Test daily, if not integral to the drill unit store in a safe place. Many of these items are very basic, but often overlooked in day-to-day operations. It is crucial in today’s economy to look for every advantage you can gain to maximize efficiency.
Following these suggested maintenance schedules will help you get the most out of your investment.
Richard Levings is a Product Marketing Manager at Ditch Witch, based in Perry, Okla.
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