Arizona Metro Mix (AMM) is a four plant, 42 truck contractor/producer providing concrete to the Greater Phoenix Metro Area. In that market, the temperature range spans from 90 degrees Fahrenheit (32 C) at sun up to over 120 degrees (49 C) during the latter part of the day. Controlling the slump, air, and color content of mixes in this environment is already challenging, but AMM also contends with changing sand equivalency (SE 1) which can vary by nearly 35% over a period of a few days.
AMM was awarded a job where the concrete, with tight requirements for air content, was required to be delivered up the side of a mountain. Bob Matthews, Operations Manager for AMM, originates from Michigan where air entrainment is used all the time. However, they don’t use much in Arizona, and historically, the company had struggled to contain entrained air variation to no more than one and one-half percent (± 1.5%) from load to load.
AMM doesn’t have a separate QC department, and they had used probes before which were, in their opinion, only slightly better than nothing. Sand coming in from the quarry varies from 0% to 4% from load to load, with an upper range of 12%. Using the probes AMM has historically used, if the incoming sand varied by more than 2%, they would have to recalibrate. Since the material was constantly coming in, AMM was always “chasing” the moisture and slumps were “all over the place.” Recalibration with the old probes was frequently required three times per day.
Find out how the Precision Water System (PWS) became the answer to AMM’s challenges and helps them to deliver consistency and superior service to their customers.
Want to learn more about PWS? Check out this blog to learn more about how you can Control Moisture Content of Every Batch.