Yes. Even though our pullers can create up to 20,000 or 40,000 pounds of line pull, they can only create that if there is that much resistance to the pull. If there is only a 100 pounds resistance, our puller only creates enough to overcome that resistance. For fibre optic cable, we suggest you utilize a capstan on the auxiliary drive shaft rather than the main reel drive. We suggest the capstan marketed by GMP that utilizes a slip clutch to protect the fibre-optic cable should the resistance exceed the cable strength.
The low oil pressure warning light comes on when the engine is at idle. Do I have an oil pressure problem?
Probably not. The oil pressure sender unit requires 5psi to shut the warning light off. At idle, the Wisconsin VH4D engine produces less than psi, yet it is operating correctly. You should be concerned about oil pressure if the light comes on when the engine is running at medium to big rpm’s.
If the cylinder that raises and lowers the idler wheel on the Hydra 985 is double acting, what are the big springs for?
The torsion springs that operate between the lower “A” frame of the idler wheel and the front frame member, are designed as a redundant safety feature. They are there to insure that the idler wheel can never “bleed” down while the trailer is in transit. The springs are designed to hold the entire weight of the idler wheel in position, even if the cylinder was totally disconnected from the system. The only way the idler wheel can come down is under power.
When you bring the drive rollers against the reel flanges, make sure all rollers are against the flange and the pressure is just enough to show visual indentation of the roller material. This is enough pressure to safely transport the reel (remember, the power unit and drive -rollers act as safety to guard against the reel shifting forward in the event of a sudden stop.) This is also enough pressure to initially turn the reel at the job site. If the rollers slip during the pull, apply just enough additional pressure to get the reel turning again. Repeat additional pressure as required when the rollers slip. In this manner you only use the pressure required to complete the pull. This method will save lots of wear and tear on the machine.
There is no practical way to measure the pressure between the drive rollers and the reel flanges. A pressure gauge on the power unit cylinder is susceptible to false readings and therefore can become a safety problem. Any readings at the cylinder or extrapolations of such readings would vary from pull to pull depending on the cleanliness of the slide rails, the lubrication to the rails, the internal integrity of the cylinder and other factors that make it totally unreliable. The best way to determine the pressure is ratio of the drive roller material against the flanges.
Since our lifting cylinders work in the vertical position, we allow gravity to work for us. This saves a lot of damage to paved surfaces, too. With our system, when the reel makes contact with the ground, it stops. With double acting cylinders an operator could inadvertently push the reel through the blacktop. It’s happened plenty of times. On cold days it may be necessary to run the unit to warm the hydraulic fluid to make lowering easier. You can also turn the engine off, which eliminates some hydraulic back pressure and allows the lifting mechanism to come down easier.
We believe firmly in the principal of transferring the load to the frame of the trailer. This is accomplished by allowing the lifting mechanism to settle onto mechanical locks, which are mounted to the frame. This removes all strain from the hydraulic system. A loaded reel bouncing down the road can exert tremendous shock loads to a hydraulic system. We feel steel to steel mechanical transfer of the load to the frame is much safer and reliable.
The primary reason we do not offer remote control is safety. The secondary reason is maintenance. Lets tall about the safety aspect. Most people automatically equate remote control as safer. This is not necessarily so. Our pullers are designed to be operated from specific operator positions at either the front or rear of the unit. If the operator stays at those positions, he can see everything he needs to see and control everything he needs to control to perform his job correctly. And at those positions, he is not likely to put himself” in harms way.” With a remote pendant, the operator would have the ability to “stray” into a position that might put him in the “bite of the line.” We feel cable pulling machinery has to be operated “hands-on” to be safe. Our second concern, though less important an safety, is maintenance. All forms of remote control, be they hard wired, radio or infrared, require substantial maintenance. Each connection is another potential failure point. Elimination of such connections alienates those potential failures.
I’ve used the Hogg Davis puller fox underground pulling but never overhead. Now I’ve got an overhead job. Will it do it?”
YES! Long before we earned our reputation for underground pulling, our machines were pulling both power and telephone cables overhead. They work great for reconductoring, removal or new installation, Your standard rigging procedures that you currently use for overhead will probably work just fine. Set the machine up the same as you would any type of puller. Always try to set for longest lead angle as possible. This helps relieve the strain on the crossarm or pole nearest the puller.
Assuming you’re already in the lowest gear range and the engine is running at optimum horsepower rpm (1800-2000), the reel you are using is probably the culprit. Our machines, like all cable pullers, are nothing more than huge winches on a trailer frame. Maximum power, like a winch, is at the first wrap on the drum. With a friction drive puller, like ours, the power is applied at the outside diameter of the reel, rather than at the shaft. Therefore, the greater the outside diameter in relationship to the core diameter, the greater the leverage more power. Our pull ratings are established using our 805O BreakAway Reel. This reel has and outside diameter of 80″ and a core diameter of 24″. If you subtract the radii (40 minus 12 = 28) you determine you have a “lever” 28″ long that you are utilizing. Try to use reels that have the longest “lever” to get the most power. Also, try to use reels with wide flanges, This provides more friction surface against the rollers for optimum power.
My boss says that once you start a pull you can’t stop because you’ll never get the cable started again. Is that true?”
Your boss has probably had a bad experience at one time or another when that was true. However, in our experience, that is not the rule. This situation usually only occurs in removing underground cables. Depending on how long the cable has been in the duct, the type of cable, type of sheath, type of duct and its condition all play a part in the ability to get the cable out of the ground. The greatest amount of force required is usually at the beginning of the pull. Once the cable breaks loose, the amount of force required to move the cable drops way off. It’s much like pushing a car. The greatest force is getting it rolling and from there it gets easier. From a time efficiency standpoint it makes sense to keep going once you’ve got it started. However, if you must stop for safety or rigging problems, you shouldn’t have any problem restarting the pull.
Some jobs we do go real easy and then it seems the next job is really tough. But the jobs have the same footage of cable, what gives?
Since I am not on your particular job I can’t give you a definitive answer. However, there are many aspects that effect pulling ease besides the amount of cable. Some of those are cable type, cable sheath, duct type and condition, number of sweeps and their angles in the duct and duct cleanliness. A duct that has flooded many times over the years and filled with silt is always a tough pull. Electrolysis and lead sheath cables create a situation where a cable can virtually weld itself to the duct. A duct that has cracked or settled can create tough pulls. The easy ones are always nice, but a lot of things can be going on down below that will make it tough.