The Low Down on Load Index

In backhoe operations, the tires you select play a key role in maximizing your uptime. The durability of your tires, which is critical for avoiding costly downtime, can be affected by a variety of factors such as puncture resistance and sidewall construction. An additional factor you shouldn’t overlook is your tire’s load-carrying capacity.

“With today’s bigger machines, you need to be aware of your tires’ load-carrying capacity, because consistent overloading  — especially on the front end — can lead to accelerated wear and even premature failure,” says Todd Gillespie, North American training and development manager for Michelin Agro-Industrial Tires.

Load index is the most accurate measurement of load-carrying capacity. Every tire carries a load and speed index rating that signifies the maximum load that tire can carry for the particular speed of operation. For instance, a Michelin XMCL 500/70 R24 rear tire has a load index of 164A8/B. The A8/B signifies the speed rating. In this particular instance, the tire is approved to operate at speeds as high as 30 mph. The 164 rating signifies the actual load rating. The load index of 164 indicates the tire can carry a maximum load of 11,020 lbs at a speed of 30 mph and an inflation pressure of 58 psi.

To replace tires on machines you can accurately determine the load index you need by following this process:

1. Load the front bucket to capacity with the heaviest material the backhoe lifts in its typical applications, then weigh the front axle to determine the maximum load the front tires will carry.
2. Dump the load then weigh the rear axle. This will represent the maximum load the rear tires will carry.
3. To optimize your tires’ performance, refer to the manufacturer’s data book or Web site to select the recommended tire inflation pressure based on the heaviest load at the highest speed of operation.

Dan Kirkpatrick is an associate director at Osborn & Barr Communications based in Des Moines, Iowa.

Tension Getter

A Little Tension Can Be Great for the Relationship of Track and Machine

By Ron Waters

Tension isn’t always a bad thing. While you may not want to feel it when you enter a room, you do want to see it in your rubber tracks. Proper care and maintenance (and thereby tension) can extend their lifetime, providing you with a long and prosperous life together. Extended rubber track life will reduce costs for the repairs and replacement of what is often an expensive and key component of compact equipment.

Riding your mini excavator or compact track loader without enough tension on the tracks can lead to numerous  problems. One of the more severe problems includes the track slipping loose and detracking, followed by the sprocket cutting into and tearing the rubber track. These tears can widen into large chasms that eventually require replacement of the track.

Partial slippage also creates problems resulting from the sprocket riding on the projections of the metal embed. This pressure can cause the metal embed to break loose from the rubber track — just one separated metal embed can require the replacement of the entire track. This same situation can also cause the steel cord in the rubber track to break and  reduce the strength of the rubber tracks.

To prevent these problems, you should check the tension of your rubber tracks after every 50 hours of operation. Tension can be identified at the midpoint of your track, when the machine is raised and there is no pressure on the track. There, you should be able to move or flex the rubber track about 10 to 15 mm. If not, an adjustment is in order. Consult your owner’s manual to learn how to adjust the tension on your particular machine.

The rubber tracks should also be washed to remove any debris in between the rubber track and the metal undercarriage components. This debris can gradually grind away the surface of the rubber track on the track roller side, exposing the embedded metals. Consequently, the embedded metals will corrode, resulting in their separation from the rubber body. This process may be accelerated in environments that are particularly corrosive, such as compost spread grounds.

Ron Waters is a rubber track aftermarket sales specialist for DRB America Inc., based in Cerritos, Calif.

Chain & Things

Insider Insights to Buying a New Trencher Chain

By Al Chancellor

Earth eaters go through lots of teeth. When you spend most of the day sawing through soil and rock (just like a compact trencher does) you will on occasion need a new set of steel chompers. It may appear, on the surface at least, that picking a new chore chain for your trencher should be a quick and easy decision. However, there are myriad factors to consider when shopping for a new chain for your trencher.

First off, you’ll no doubt hear buzz phrases like “tensile strength of the chain.” Tensile strength, simply put, is the amount of stress or force required to pull the chain to its breaking point. While the tensile strength of the chain is important, so is the horsepower of the machine and the chain drive capabilities, which will ultimately determine the pitch size of the chain category and the corresponding tensile strength. What is especially important are the innovations to these chains, which offer longer life and increased shock loads. Offset rivet placement, anti back-flex side bars, special alloy steels and precision manufacturing and assembly processes are what truly separate the quality of these chains.  

A good question that should be asked is: Who manufactures your chain? There are few companies in the United States that manufacture this type of product and learning where your chain is coming from will make your decision a great deal easier. A good trenching system requires matching the system to the equipment, as well as the ground conditions. This will increase productivity, extend component life and reduce wear and tear on the machine itself. It doesn’t matter if you are trenching in sandy loam or schist rock, if you don’t have the correct cutter style and pattern arrangement, you will be unable to maximize your production. Since the majority of trenching contracts pay by the foot, production is the single most important factor to consider and any unforeseen downtime directly relates to lost revenue.  

Price is a whole different animal. It really requires evaluation in relation to hours in use, the cutting system being used, ground conditions, operator experience, downtime and the associated labor. The best combination of these variables will provide the best overall value and obviously, the cheapest chain is rarely the best option. If you use price as the sole determinant for a trencher chain you are taking a significant risk and it will most likely cost you much more money in the long run.

Six Major Chain Options  

1. Cup Cutter Chain — Curved metal teeth with a penetration point and hard faced cutting edge. Primary application is light to medium soil conditions.
2. Combo Chains — A combination of conical carbide teeth in adapters used in conjunction with cup cutters or fixed terminator/shark teeth and cup cutters. Primary application is medium to hard soil conditions.
3. Bolt-On Terminator/Shark or Alligator Chains — Complete chain assembly with bolt-on fixed carbide teeth or rotating carbide teeth and adapters. Primary application is medium to hard and lightly compacted rocky soil conditions.
4. Welded Terminator Chain — Low-profile attack angles via solid weld construction using fixed carbide Terminator/Shark Teeth. Primary application is medium to hard soil conditions including various rock formations.
5. Welded Alligator Chain — Low-profile attack angles via solid weld construction using conical carbide teeth. Primary application is medium to hard soil conditions including various rock formations.
6. Welded H-Plate Chain — Low-profile solid weld design with conical carbide teeth and incorporating stabilizing segments for block protection and spoil removal. Primary application is medium to hard rock soil conditions.

Al Chancellor is a marketing manager with Ballantine Inc., based in Anoka, Minn.

All-Terrain Trooper

Camoplast’s Go-Anywhere Utility Vehicles Travel Lightly on the Ground and the Environment

From the glacial valleys of the Canadian Rockies to the mud-covered subtropics of Florida’s swamp lands, Camoplast’s Trooper vehicles can tackle almost any terrain to get the job done. The Trooper, and its larger and smaller siblings from Camoplast (based in Granby, Quebec), can be found supporting everything from mineral exploration and power line inspection to back country search and rescue operations all over the world. It’s especially versatile in the high country.

“It’s a rugged, lightweight, four-season tracked carrier for snow and rough terrain that can be counted on to perform in the most challenging conditions,” says Christian Martin, the sales and marketing director of Camoplast Industrial Inc.  “It is particularly effective in deep snow, high altitude and extreme steep slope conditions.”

Limiting ground pressure is one of the keys to designing a vehicle able to move efficiently over soft surfaces like sand, mud or snow, and tracks are one of the best technologies available for reducing ground pressure. The Trooper has a four-person cab and is offered with a choice of five different track options, including both steel and rubber construction. The Trooper cab is heated, comes with adjustable front seats, seatbelts all around, front and rear wipers and even a sunroof and coat hangers. It can be upgraded with additional lighting, brush guards, premium seating and an AM-FM stereo radio with CD player and multiple speakers. When you consider that the Trooper only weights 3,000 lbs, it’s easy to see why this go-everywhere vehicle is widely used to move people and equipment through some of the most inhospitable climates to reach some of the most inaccessible places on earth.

“Fully loaded, one of our Trooper vehicles weighs in at 10,750 lbs,” Martin explains. “Yet when equipped with a set of 44-in. wide tracks, it has a ground pressure of only 0.90 psi. Compare that to the 9 to 12 psi of ground pressure of an average man walking and you can see why the Trooper easily can traverse terrain that a man literally cannot walk through.”

Powerpoint

Perkins Engines OEM’s the Troopers’ Diesel Power Plant  

The “power” part of the power to weight ratio on the Trooper is supplied by a four-cylinder, 4.4-liter Perkins 1104C-E44T diesel engine that produces 115 hp at 2,400 rpm, and 325 ft-lbs of torque at 1,400 rpm.

“Considering the kinds of places these vehicles spend most of their time, reliability and ease of maintenance are both critical,” Martin says. “And so is the availability of service and spare parts literally anywhere in the world. Those are all reasons why we settled on the Perkins diesel engine to power the Trooper and its siblings.”

“The 1104C family is a well-proven design that’s in service all over the world,” adds Marc Lepage, development manager for Master Distributor Perkins Quebec & Maritimes (PQM). “It has standard features like single-side servicing and a 500-hour service interval that make it ideal for tough, demanding applications like the Camoplast Trooper.” RS# 37