The selling and retailing of concrete is a basic concept in which that many companies through out the world engage in. The traditional method involves a centralized batch plant loading a specified amount of materials for concrete into a Bbarrel type drum which is mounted on a truck chassis. The materials are then mixed in transit as the barrel rotates while the truck is traveling to the job site. This is by far the most popular way of delivering retail concrete. Concrete companies and the ready mix industry have literally transformed into major corporate operations as many small producers from the 1960's and 1970's were bought out by major corporations such as Lafarge and Aggregate Industries.
The major emphasis for many of these companies is to deliver as much volume they can (naturally at the highest price they can). The competition becomes extremely competitive when you are talking about tens of thousands of yards that are up for bid and most of the major producers are geared for this type of business. While most of their business models are designed for this type of work it can become difficult for them to provide smaller amounts of concrete competitively. Many times large ready mix companies will have minimum order requirements. Pending the location and market this amount can range from 3 to 6 yards of concrete. Consequently, many small contractors and users are faced with higher production and projects costs as result of this model.
The volumetric industry was in part founded on this concept as the Daffin "Concrete Mobile" (now a Cemen Tech Company) was truly the first manufacturer to have an impact on the market by selling and producing volumetric mixers. The design and concept of the Daffin Concrete Mobile had (and still does have) several simple yet important advantages.
One, the materials for concrete are stored separately enabling the user to produce fresh high quality concrete at the job site. Concrete by nature is a perishable product with a shelf life once it is produced or mixed. If it is not placed in timely manner it will set up and be useless. A volumetric mixer enables users to accommodate delays on job sites, travel long distances with out having the hydration of the mix becoming a problem and finally the ability to make concrete on the site at the exact water cement ration required by the customer. All of these advantages translate to a user friendly product for the concrete industry.
The second advantage is that a volumetric mixer user can produce or literally batch as much as ten cubic yards or as little as a shovel full if required during a delivery. (NOTE: Model and carrying capacities vary. The Volumetric Mixer Manufacturers Bureau is an affiliate of the National Concrete Ready Mix Association and is the governing body that ensures capacity and production rate standards are met by its members for the industry. Go to www.vmmb.org to find out more).
The ability to produce an exact amount of concrete removes any guess work from the contractor's side of the ordering equation of a retail transaction. This is an advantage as end users need pay for only what they use if they over estimate the yards of concrete required. In addition if they order short they need not worry about having to call for another mixer truck to the site for that last quarter cubic yard they ran short already there and ready to produce that shortage on demand.
Three, each volumetric mixer (pending manufacturers recommendations) is calibrated by weight and should be done so in accordance with ASTM C-685 and ACI 304.6R-09 standards. While the actual mix and proportioning of the materials for concrete are indeed done via volume, the mixers themselves are calibrated by weight and then tested via yield much like a gas pump. All of these advantages not only play to retailing of small amounts of concrete to the job site but also to any other application requiring concrete in any amount. There is an entire market for many owner/operators of volumetric mixers who specifically deal in delivering small yardages of concrete that many of the large ready mix companies avoided. In some cases local owners work hand in hand with the local dispatchers at the Ready mix company and they refer their large pours to them and the dispatcher in turn refer the small pours back to the volumetric mixer owner.
Large ready mix companies themselves have seen a niche and have added another profit center by adding a volumetric mixer or two to their fleet for filling in the gaps for short load deliveries or concentrating on one of the other markets mention our web site.