What happens if I don’t get vibration out of my equipment?
/If you don’t get the vibration out of the equipment, it will fail prematurely. Once you have vibration, it will compound until the equipment has failed.
If you don’t get the vibration out of the equipment, it will fail prematurely. Once you have vibration, it will compound until the equipment has failed.
If multiple equipment is set on the same foundation, one piece of equipment can pollute the other piece of equipment causing a sympathetic vibration.
For rotating equipment, the foundation mass should be three times the mass of the equipment. For reciprocating equipment, the foundation mass should be five times the mass of the equipment.
Concrete needs to be completely hydrated which is typically 28 days with standard concrete. Concrete could be hydrated faster than 28 days but would need to be tested to verify full hydration.
Assuming the concrete is properly cured, grout can be poured after all concrete laitance is removed.
A concrete foundation should be prepared for grout by removing all laitance with a chipping hamper with a chisel bit.
A foundation should be between 65°F to 90°F to install grout. Having the right temperature is important to ensure proper flow, adhesion and cure of the grout material.
The depth of the foundation should be beep enough to properly embed the anchor bolts. This would vary based on the size of the equipment. First, consider the mass required for the foundation. Next, consider the 30 degree rule for a stable footprint.
All concrete should have a minimum compressive strength of 4000 psi at 28 days.
Remove all laitance with a chipping hammer.
Make sure the concrete is properly hydrated.
Be sure the concrete is free of any oil or contaminants.
Multiple concrete pours are not recommended as there will be a cold joint between pours and vibration will not transfer across a cold joint.
A cover may be necessary to protect a foundation from sun, wind and rain.
The foundation should be covered to keep the grout from being exposed to direct sunlight.
The foundation should be completely enclosed and provided with a heat source to raise the entire foundation and equipment to a temperature above 65°F for 48 hours prior to and after a grout pour.
It is unacceptable to sand blast a foundation in preparation for grout. Preparation will need to be done with chipping hammers. A chipping hammer will properly profile the foundation and remove the laitance layer.
A high early concrete should only be used with the approval of the equipment user. Consider the use of Gill 33 for quick compressive strength and hydration.
Equipment should be set on separate foundation as not to pollute adjacent equipment with sympathetic vibration.
It should be big enough as to not violate the 30-degree rule.
The 30-degree rule is a best practice. If you drop a plumb line down from the center of the rotation shaft and rotate this line 30-degrees in both directions, the line should go through the bottom of the foundation and not the side. This will ensure stability of the foundation.
All existing foundation contamination must be removed by removing the concrete that is contaminated prior to grouting.