Monthly Archives: January 2021

Rexcon Concrete Plant Review – Concrete Plant Marketplace

Rexcon is an old line company that is well respected throughout the concrete production industry. They have produced quality equipment based on proven designs for a very long time. The company is most well known for their high production central mix paving plants, however they are pushing to become more well know in Ready Mix, Transit Mix and other types of wet and dry concrete plants.

The quality of Rexcon plants has always been good even as the brand has gone through ownership changes. In 2003, Rexcon was purchased by its Illinois based distributor and has enjoyed enough success to relocate in 2009 to a newly built 30 acre campus they boast as a showpiece. The Rexcon flagship plant is still the Model S, high production concrete paving plant, but under new ownership the company has expanded their line of portable and stationary concrete batching plants.

The overall core design of Rexcon’s most popular plants has changed very little. The Model S plant for example proved to be a reliable high production plant that was easily transported and erected. The overall design and construction of a newly constructed plant and an older plant are substantially the same. This is a testament to the quality of both design and construction of Rexcon plants. Conversely, the company has been criticized by some for their reluctance to move toward emerging design and technologies such as twin shaft mixing.

The pricing of new Rexcon plants tend to be in line with similar plants manufactured by well respected and proven companies. Rexcon plants are not cheap by any stretch, but when considering their proven design, high production rates, and quality construction their pricing is acceptable. Pricing of used Rexcon plants can vary according to the age and condition of the plant.

Older Rexcon plants more commonly than others are refurbished or rebuilt completely. While most concrete plants are maintained and have parts and components replaced as needed, it is not uncommon to find a used Rexcon plant that has been completely refurbished and is in “like new” condition. These completely refurbished systems cost much more than a used system that has years of operation and has not been rebuilt.

Comparing pricing of used Rexcon plants to other brands can prove tricky. If a customer is comparing a used normal output volume central mix plant to a model S central mix plant of similar year, the Rexcon will appear more expensive, but it is important to remember the output volume of the Model S is likley much higher than a normal central mix plant. It is important to consider all of the variables when considering a Rexcon plant with other manufacturers. The availability of Rexcon equipment is consistent. The market does not typically offer more than a few Rexcon models; and when a reasonable priced plant becomes available they usually sell quickly.

Principles of Agile Manufacturing

When facing competition-particularly fierce competition, it’s important to know all you can about your adversary and their weapons, the battlefield on which the fight will take place, and the best time to strike or retreat. In other words, knowledge is power, and the ability to remain flexible and fast to emerging or changing developments is a tremendous tactical advantage. This notion of changeability is at the heart of new movements in manufacturing based in production agility. While certainly a modern business concept, agile manufacturing goes beyond simply being another version of 1980’s-styled computer integrated manufacturing or 1990’s lean manufacturing. Rather, agile manufacturing represents a complete shift in the mindset of production industries in the 21st Century; one in which there is both a greater relationship between technology and worker skills, and greater customer access to, and demands upon, the core competencies of their manufacturers/vendors.

The basic concept of agile manufacturing is to develop what could best be called a nimble mindset when it comes to understanding market environment. In short, rapid changes in the market environment are not something to be feared, but are seen as opportunities to exploit for the purpose of beating the competition to the punch. Rapid changes in the market are moments that call for rapid responses. The manufacturer that has taken the effort to instill agility through enterprise resource planning has the competitive advantage when it comes to quickly transforming their own knowledge into new products and services for their customers. Indeed, in a global economy, market opportunities are often identified in new growth areas where wholesale and retail product needs were often non-existent until a few months ago.

In a global economy, windows of opportunity open quickly and the more agile the manufacturer the greater the rewards to be gained from being the first responder to customer needs. Such rapid movement requires more than versatility or the ability to merely adjust to changing circumstances. Expanding the customer-base through emerging markets necessitates the quick reflexes that result from the consistent improvement of business intelligence-the knowledge, skills, and empowerment of employees toward the idea of greater interaction with customers. In this light, progressive business knowledge is seen as a useful and dynamic proactive resource rather than passive data collection after the fact. That is to say, innovation in the market (innovation of product, innovation of taste/desire, etc.) provides the greatest growth opportunities for companies who are quickest because of their concerted effort to be agile.

A first step toward becoming an agile manufacturer is developing the means by which business intelligence of the marketplace is made meaningful, and production is wholly synthesized through integration. This means the employment of enterprise resource planning software (ERP) that brings all areas of the manufacturing operation into a single, real-time database where the actions of one department never happen in isolation; where all aspects of the operation are capable of responding quickly to present and emerging customer demands. Particularly suited for agile manufacturing, ERP software provides the basis for rapid communications and the exchange of data, as well as the means by which responsive actions can be quickly taken to ensure competitive advantage.

Polypropylene Bags Production Process

Manufacturing of tapes:

The granules of polypropylene bags are fed to the extruder hopper, where they are plasticized and the melt flow is passed through a T-die. Film thus produced is slit into the form of tapes. These strips are then oriented by stretching them under heated condition at a predetermined ratio. Finally the tapes are wound on cheese winders. It is also possible to produce films by blown film process, instead of T-die extrusion. The compounding ingredients used along with polypropylene and HDPE are generally CaCO3 and master batch.

Weaving of tapes into fabrics:

The tapes so obtained are fed to circular looms/ flat looms and woven into tubular or flat fabric respectively.

Lamination or extrusion coating:

This step is not necessary for all types of polypropylene bags as in case of jute sacks. Therefore, calculations were made without taking into account the energy/emission in this process. Fabric produced may require to be coated. HDPE woven sacks are laminated with LLDPE/LDPE while in case of polypropylene bags; lamination is done by lamination grade polypropylene.

Fabric roll is mounted on unwinding roll from where it passes through two rolls over which T-die connected to the extruder is located. The melt of the material, which is to be coated on the fabrics comes through the T-Die as an extrudate and coats the woven fabric. It is then cooled under pressure and wound.

Cutting and stitching of polypropylene bags:

In the next stage the unlaminated fabric as produced earlier is cut, reversed manually, and the bottom is stitched. Then it is printed as per the requirement of the customer.

Primary properties of polypropylene used in producing woven sacks are their chemical inertness and inertness to metabolic processes.

Polypropylene used for the manufacturing of polypropylene bags meets the requirements stipulated in BIS standard IS 10910. The grade of additives incorporated in polypropylene complies with the FDA: CFR title 21, 177.1520 olefin polymers. Additive incorporated in polypropylene also conform to the positive list of constituents as prescribed in BIS standard IS: 10909.

The Reflective Supply Chain in Manufacturing

The well publicised plight of manufacturing companies in the United Kingdom has led to an ever increasing demand for reduction of internal costs and now, more than ever, the focus has been on the cost of supply chains. The nature of supply chains and their structure is however often overlooked, and many of the internal costs can be eliminated by examining the overall supply chain strategy. By developing a supply chain that reflects the needs of the internal customers, many of the previously unidentified inefficiencies can be eliminated and subsequent performance improved.

There are three categories of product that can be used to define the supply chain strategy for a typical manufacturing company. Firstly there are the core products that are manufactured on a continuous basis and form the bulk of production volume in any given period. Secondly there are products that are manufactured regularly to meet customer requirements or to satisfy a recurring demand, and finally there are those products that are manufactured to specific customer requirements on an irregular basis. The three categories are sometimes referred to as Runners, Repeaters and Strangers.

There is an unquestionable link between the classification of these product types and the supply chain organisation that is required to support them. Each classification requires a different supplier strategy and stock policy in order to maximise inventory turnover. For example, replenishment systems such as Kanban may be highly applicable to components used in the Runners group because of the rates of consumption but applied to the Strangers group may introduce higher volumes of inventory on long lead time parts. The selection of the appropriate supply chain strategies will therefore lead to two distinct systems, one for the Runners and one for the Strangers. The Runners supply chain will tend to be highly efficient with a focus on component cost, quality and the suppliers delivery performance. The Strangers supply chain however, will need to respond to the irregular customer orders and the focus will be more on supplier lead time and the ability to meet these hard to forecast demands. The Repeaters are likely to incorporate both systems and require case by case decisions on which approach to follow for each component. The Repeaters therefore typically lend themselves to strategic stock holding which requires regular review but gives a defined capability for production.

The classification of the products in this way identifies the needs of production and in turn identifies the type of supply chain support required to achieve the desired output volumes. More importantly, and often over-looked, strategies based on this simple analysis are more likely to support the customers requirements.

Having defined the groups of products and the styles of supply chains required to support the differing needs of these product groups, the supply chains themselves must be developed in accordance with these needs. The resulting supplier development programme can therefore be tailored to suit the different supply chain requirements and so support production needs and in turn the end customer in the most appropriate way.

There are many tools and techniques available for improving overall supply chain performance, but few have been developed to help define a supplier development strategy.

One technique called ‘Supplier Positioning’ maps customer perception of the risk and importance of its suppliers and also most importantly, the suppliers perception of the customer in terms of importance and ease of business. This can provide useful information by identifying which suppliers are not likely to support supply chain improvements. For example, many manufacturing companies will continue to purchase relatively low volumes of parts from large retailers, whose part cost, quality and delivery is beyond the customer’s control due to the supplier’s perception of the customer being ‘low value’. These suppliers therefore have a disproportionate ability to detrimentally affect the manufacturing capability of their smaller customers.

In improving the supply chain and creating the development strategy, ‘Supplier Positioning’ can be used to ensure that the integrity of supply will be maintained by giving an understanding of how the various suppliers view the customer and the degrees of interaction required to maintain good relationships. This technique has an additional benefit in that it identifies potential weaknesses or mismatches in the supply chain relationships which, once highlighted, can be resolved.

The application of product classification and then developing the supply chain to suit the production requirements can undoubtedly help identify the strategic direction for supply chain improvement. The resulting activities will not only develop a leaner supply chain but will introduce greater control of inventory and a better understanding of the needs of the internal customers.

There is an extricable link between the three main influences within any manufacturing company. Identification of customer demand, production capability and the flow of materials to satisfy this must combine with clearly defined parameters and processes to generate the required output. Failings in any one area will cause a domino effect that will result in failure to deliver on time in full and ultimately unhappy customers.

The rate of demand defines the requirements for capability and material flow but must never be isolated or ignored as is often the case. Changes in demand or customer orders can only be fulfilled efficiently by having a balanced circle.

Each function in this model is dependent on the others and must therefore work within the same boundaries to achieve a common goal. The key therefore to reducing the inefficiencies in a supply chain lies in understanding and managing these relationships which is the start point for achieving a reflective supply chain.