Boom Chatter - Worth Listening To
Have you ever wondered how some boom truck operators seem to extend and retract loads smoothly while others tend to shake loads so badly, bindings loosen or material falls off? – (both dangerous situations!)
Besides a lack of operator experience, the leading physical cause of that shaky boom is a metal on metal condition within the telescope known as "boom chatter". Boom chatter can occur when wear pads are missing – (possibly fallen out because of loose bolts or improper installation), wear pads have been worn down with use, or wear pads have been improperly serviced and are running dry.
Our experience has shown us that the leading cause of boom chatter is poor service or lack of service to the wear pads. To be sure, some newer models of cranes include “self-lubricating” wear pads, but the fact is that all wear pads require lubrication in order to do their job and all wear pads also need to be inspected regularly to make sure they are in place and functioning as outlined in all crane operations and service manuals. (Be sure to note that the inspection and lubrication are considered to be the responsibility of the operator.)
All wear pads contact adjacent telescoping sections. When the factory installed lube wears off of the wear pads, chatter is the result. If you are concerned about longevity of your boom truck, it is imperative that you do not allow your wear pads to lose all their lube and run "dry". It is equally important to use the correct type of grease on your telescoping boom assembly. In addition to chatter, dry wear pads can also tear loose and dislodge other wear pads causing irreparable damage to the adjacent telescoping section with metal to metal contact.
The factory recommends that you lubricate your wear pads using a product with superior lubricity that functions throughout wide-ranging temperature variations such as Mag I by Lubriplate which is a lithium polymer that maintains its lubricating properties between -60 F and +300 F. There are other synthetic products available that will do as good a job as well. Stay away from petroleum-based greases such as chassis grease which will actually cause rather than correct the chatter. In lower temps it has a tendency to gel up and grab, at higher operating temps, chassis grease may melt away entirely.
Manufacturers supply us with access holes for a grease gun needle in order to get lubricant to some of the wear pads, but the most difficult wear pads to lubricate and the most likely to cause boom chatter, are those on the inner tops of the telescope sections. These pads wear against the inside top of their adjacent sections during operation and lubricant must be worked into the inside top of the sections – no small project going against gravity! Our Service Department has developed a three step process to get to these outer/inner top areas of the sections which requires an operator to extend, retract, boom up and boom down several times as our tech systematically applies the lubricant to the necessary pads an effort to work the lubricant into the proper areas. If it sounds complicated, it is - don't try this at home – Contact Runnion Equipment and make an appointment. Better yet, make sure you come to one of our maintenance seminars and we will show you how it is done!