The Iowa DOT was ready throw slip form paving out of the state. They were having major issues with vibrator trails. The reached out to both vibrator manufacturers to come up with a solution. This was the birth of the monitoring systems.
Started with a tachometer. Difficult and dangerous to take a reading while paving Auto Vibe 1: Could see speeds but you would have to manual write them down if need a record Auto Vibe 2: See the speed and record the data Auto Vibe 3: Visual, record and control form the monitor The grey monitor was a system change were we moved from Muxbus to Canbus communication.
Slow down the vibrators. A federal highway study states the best vibrator range is 4000 vpm – 8000 vpm. 4000vpm gave them the best product but 8000 vpm gave them the best looking product.
Oil takes the path of least resistance. Contractors will have a mix of vibrators (New, used and really really really used) Needless to say just because you set each valve at the same point does not mean those vibrators are running at the same speed. Sensored vibrators and a system to read them out allow you to make adjustments to the flow to make all vibrators run at the same speed. If the rest are consistent (Rotors, spacing and paver speed) then the are taking the variables out.
Not every load of concrete placed in front of the paver is the same. Lower slump (more like peanut butter) will slow a vibrator down. Higher slump (more like soup) will speed the vibrator up. This is actually opposite of what the vibrator should be doing in these conditions.
What you end up with is more like the top. Different hydraulic flow to different vibrators, some worn, some new etc. Cause for a wide range of speeds across your pan. What the concrete needs is a consistent speed (One which works the best for the concrete) across the paver.
We have two systems that can achieve that. Auto Vibe 2: which monitors the vibrators and records the individual readout while paving. However the operator will still have to make individual adjustment controls at the manifold. Auto Vibe 3: which does what AV2 does but it puts the controls at the monitor. It will also attempt to hold that set VPM so if the concrete loads very or a vibrator start to slow down it will give or restrict the flow of hydraulic fluid to maintain that vibrator speed.
Systems is easy to install. We will mount the monitor up near the operator location. Depending on how many vibrators your paver has will depend on how many controllers (Silver Box) the system needs. These boxes are what gathers the readouts and sends them to the monitor. The controller reads up to 8 vibrators each. The monitor and the controllers require power cables run to them. Then we will connect all the communication lines and configure the system. If the ground speed wheel or temp humidity options are ordered then we will install those as well.
Every vibrator will require a accelerometer. You can either order new vibrators with the accelerometer installed or order the accelerometer kit and install it into and existing vibrator. The sensor goes over the vibrators hydraulic hoses and sits against the hose barb on the vibrator head itself.
We can sensor any make of vibrator. We have systems running on all makes. Including electric vibrators.
We will come out install the system and train in one day. If you time this for the day before you pave we can stick around for the first day of paving.
In the next few slides we will go over what the operator will see and the various functions of the monitoring systems.
Probably the most important thing is the operator will know the exact speed the vibrators are working. Large view is a bank of 8. You can scroll through all of them individually or page thru 8 at a time. Smaller bar graph = global view of the entire system. This allows the operator to determine of there is an issue by a quick glance.
With the ground speed wheel option you can get a speed readout on the main screen. With the Temperature / Humidity Option you will get the temp and relative Humidity readout on the main screen These options
Auto Vibe 3 allows for control of the vibrators at the monitor. The bottom icon is the vibrator on/off icon. You can set the vibrator speeds individually by highlighting the vibrator number, pushing the big dial in to select that vibrator and then adjust the speed up and down by turning the same dial. You can also globally adjust the speeds by selecting the top icon and then using the dial to adjust them all up and down. If you have all of the vibrators adjusted the same but the two edge vibrators are slightly slower. When you use the global icon it will hold that difference. For example if they are all set at 8000vpm except the edges are at 6000 vpm, if you global adjust them up 1000 vpm they will be 9000vpm and the edges 7000vpm.
You have the options to set vibrator alarm ranges. For instance if the specification states the vibrators must run between 6000vpm – 8000vpm. Make that your alarm range and if a vibrator falls out of the range then it will notify the operator.
You can choose what you would like to save to the report.
The basic record satisfies most state specifications: If will record time/date vibrator readout. If you have the ground speed wheel or temp humidity option it will include those readings as well. Plus anything additional you manually input.
It will automatically record by time, distance (if you have the ground speed wheel option) or whichever occurs first. You have select how you want it to record. This has been determined most the state specifications we have seen.
If you do not tell the system to record it will not record. You will still see all the readouts and be able to make your adjustments but at the end of the day you will not have a report.
Since the system only takes a snap shot of what the vibrators are doing however often you tell it. There maybe a time when you want to take a snap shot independently of the automatic ones. For instance you get a truck load of concrete that you do not like. Take a snap shot so you can see in the report that the vibrators and the paver was doing what they are suppose to if there is an issue down the road.
You can manually record landmarks.
You can manually input slump and air entrainment. I rarely see anyone utilize this.
At the end of the day download the report and delete the data from the monitor.
Report down loads to a USB and can be opened in Excel, Word or Works
Proposed Electronic Vibrator Monitoring Specifications = Auto Vibe 2 with the optional ground speed wheel.
Paragraph 9 of Subsection 601.02 is amended to include the following:
e. For slip-form construction, an electronic monitoring device displaying the operating frequency of each individual internal vibrator shall be required for the construction of mainline pavement exceeding 600 feet in length. (1) The monitoring device shall have a readout display near the operator’s controls visible to the paver operator and to the Engineer. (2) It shall operate continuously while paving, and shall display all vibrator frequencies with manual or automatic sequencing among all individual vibrators. f. (1) Each vibrator monitor shall be routinely checked for functionality and adequate frequency no less than once an hour or 300 feet of paving, whichever is more frequent. (2) If a vibrator monitor fails to function properly, a hand held device may be used until the monitor is repaired. The Contractor shall measure and record the vibrations of each vibrator at least once an hour. g. (1) For projects having 50,000 or more square yards of mainline pavement the electronic monitoring device shall record the following information: i. the clock time ii. station location iii. paver track speed iv. operating frequency of individual vibrators (2) These recorded values shall be made after each 25 feet of paving or after each 5 minutes of time, whichever is more frequent. (3) These recorded values shall be provided to the Engineer at the end of each day’s placement on paper or in an electronic format suitable to the Engineer.
Visit us at WOC booth C5382 and get a demonstration in person.
The Minnich Auto Vibe System
• Why Auto Vibe
• Installation and Features
• What will you need in Nebraska