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Our Services
Condition Surveys of Grout and
Foundation Status
 Review of history of installation, outages and vibration levels. Analysis of foundation design and construction, with calculations of mass and evaluation of form. Identification of actual and potential cold joints, stress risers, and stress-induced cracking. Analysis of support system, including the original grout and anchor bolts. Analysis of grout disbonding, corrosion, oil degradation and other anomalies. Verification of levels and deflection readings. In addition, at the clients request, we can take core samples to check various parameters, such as carbonation testing (phenolphthalein test), chloride testing and directly measured compressive strength. Other possible tests include Schmidt hammer testing, ultrasonic p-wave and s-wave testing, impact-echo testing, eddy current rebar location, etc. Preparation of report indicating recommended actions.
Foundation Repairs
 The basic philosophy behind our approach to foundation repairs is to restore the integrity of the concrete block and to assure that it performs its functions as a vibration damping device - the primary purpose of a foundation. Having identified the cracks and separations, we design a repair procedure to resolve the cause or causes of the cracking, and not merely fill the cracks themselves.
The stresses which form the cracks are at right angles to the plane of the cracking and we drill through the foundation to install epoxy cores with a high-tensile strength steel backbone for the repair to insure that the original stress are counteracted and the life of the foundation extended by ten or more years. In cases where lack of sufficient mass is part of the problem, we will work with a local contractor to add concrete where necessary, and bond it to the original concrete using our pressure injection techniques.
Contact us for specific examples relevant to your industry.
Alignment
 We all agree that machinery will perform better when it is properly aligned. The snag is that word "properly". We believe that all machines have an optimum alignment profile, which takes into account the changes in the shaft train when the unit is operating. Differential thermal growth, rotational displacement, and foundation fastening restraints all affect the final position of the shaft/shafts, and need to be considered.
Due to our wide experience with all types of rotating machinery, we can often predict the offsets required with accuracy. Where doubt exists, we can measure the movements of the machine casing during shutdown, using precision optics and laser-based systems, and factor the measured offsets into the final re-alignment.
Regrouting
Having achieved a good alignment, we ensure that this is maintained over many years by grouting the machine base with a high-quality epoxy grout, designed to perform in the hot, shaky, oily environment of rotating machinery. Our basic philosophy is to grout the machine directly to the foundation, removing shims, wedges, chocks, and soleplates, except where they are absolutely necessary, or required by the client or the machine designer. We also pour the grout up the side of the machine to provide lateral and longitudinal support in additional to the obvious vertical support. We will check the condition of the anchor bolts, and the fastening load used, to make sure that they are matched by a suitable grout strength and bearing area. We check the material strength of the bolts and the specified torque to ensure that the fastening load of approximately 50% of the yield strength is utilised. Under-tightened anchor bolts are a major source of broken bolts, and machinery problems.
Product Sales
The benefits of using epoxy grouts are most easily seen in a repair or rehabilitation project, but they will perform very well in new installations of all types of rotating machinery, with the following provisos:
1) The right product for the job must be used. Epoxy grouts come in several flavours: high-temperature types (150º C at the footing); underwater or moisture-tolerant types, which can be very useful when working in the open in a wet climate; low-temperature curing types - good for winter projects, or high latitude/high altitude projects. Please consult us well in advance of the installation date for specific product recommendations, designs and procedures.
2) The product must be used correctly! Make sure the contractor using the product knows what he is doing. If in doubt, ask us to supervise the job, or do the installation directly. The value of the product appears when it has been properly stored, handled, mixed, poured, placed, and finished; under a machine which has been properly prepared, cleaned, deburred, edges ground, corners removed, etc; with anchor bolts that have a suitable embedment length, and a suitable isolated stretch length; on a concrete foundation that has been properly designed, cast, cured, surface prepared, cleaned, etc.
As the only epoxy grout manufacturer with its own contracting arm, Alphatec Engineering is uniquely placed to give you the best combination of products and services.
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