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Preactor injects production planning and accuracy into Tex Industrial Plastics
April 2011
tex01.jpgEstablished in 1977 with the original name of AK precision mouldings, Tex Industrial Plastics is a leading UK based trade injection moulding company that delivers solutions to approximately 55 different customers across a wide range of market sectors including water heating, washroom products, fire safety industrial, and automotive. When the £10m turnover company with its 120 strong full time work force needed a production planning and scheduling solution to inject increased accuracy into its business, it found the perfect match with Preactor. The company’s core business is converting a wide range of commodity and engineering polymer into plastic injection mouldings.

However with each customer requiring very different products and with order sizes ranging from 200 to hundreds of thousands, this is not by any means straight forward. 90% of all orders are received electronically with the customer services team assessing each order and comparing it against a rough capacity plan to check to see if the order can be produced within the required timescale. Lead times are typically 4-6 weeks although Tex’s largest customers work on a rolling call off basis which further complicates things. Once an order is accepted a provisional Works Order is generated by the company’s UNIX system and capacity is soft-allocated. As the production date draws nearer this is then hard-allocated on the plan.


tex02.jpgThe actual production process is relatively straightforward. Raw materials are injected into the required mould and then subjected to any secondary value-add operations before being packaged and dispatched to the customer. However, as Production Director Guy Sentance explains, the reality is anything but straightforward. “To begin with, the correct raw material must be purchased in varying quantities depending on the nature of each order. Leaving aside the unique challenges of our largest customers, the sheer scale and variety of orders we process and a throughput of these core materials in excess of 20 tonnes per month, means that we have to keep track of a huge amount of materials at any one time.”

In total Tex Industrial Plastic processes approximately 160 tonnes per month with an annual value of circa £3,000,000. He continues, “Next we have to determine which orders require which presses and given the fact that certain orders require specific presses, this again adds to our capacity management issues.” Overall Tex has 38 presses ranging from 22 tonnes to 1000 tonnes with these split into 2 moulding areas. Area one contains presses between 270 and 1000 tonnes and is fed directly by automated hopper whereas area 2 contains presses between 22 and 270 tonnes which is fed by a combination of automated and by hand. In addition to this, approximately 20% of the presses are dedicated to the company’s largest customers that operate on a rolling 3-4 day call off basis.

As Mr Sentance explains, even this is not straight forward. “Our largest customers have block capacity reserved based on their estimated requirements. As the production date nears they may for example suddenly decide they need 60,000 of a product and not the 20,000 we had been anticipating. This understandably challenges not only our planning flexibility but also our production capacity as well as our raw materials levels. Because of this we have to keep buffer stocks of a variety of materials which again must be managed accurately.”

The company also offers numerous added value operations to ensure that its customers receive the most sustainable cost effective solution. These include Part Decoration/Printing, Part Joining via vibration and ultrasonic welding, General Assembly, Technical Assembly and Testing and 6-axis Robotic Sealant Application. Highly sequence dependent, these operations are all potential capacity constraints and again require careful planning. Mr Sentance adds yet another planning constraint, human resource. “It is very easy to have peaks and troughs of demand for workers and we only have a fixed amount of permanent labour we can use. If we need more labour this means having to employ costly short term agency labour whereas we can also have the reverse with permanent staff not being used to their full potential.” He goes on to add the other planning challenges include a high degree of sequence dependency on orders with certain orders being much more efficient if grouped together or following one another. The purchase and planning of externally bought products is also a consideration.

Prior to Preactor, Tex sought to overcome all of the above challenges by a combination of its UNIX system and a manual magnetic planning board. The result was that it was simply impossible to keep on top of all the products, all the orders, the raw materials, and even the plan because the planner had to continually cross reference 3-4 data sources. The planner transferred all order data of UNIX, manually generated a plan on the magnetic board, and then had to transfer this data back onto paper to distribute to the production floor. This took so long, typically 2-3 days each week, that the planner would need to cross reference back with the UNIX system in case anything had changed. And if a change had occurred the process would need to be repeated from the start. The lack of visibility of accurate data also impacted the customer services team’s ability to give accurate due dates in the first place and also provided no forewarning of orders with problems until they happened meaning that the first the customer heard was after a problem had already happened.

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In 2004 Tex decided it needed to address the problem and after an initial review of a number of planning systems the company was given a presentation by Preactor showing the capability and benefits of the system. More importantly, the company could see how Preactor could work in its own planning situation. Mr Sentance again, “Preactor clearly had excellent constraint and capacity management, was easy to integrate to our existing database and was obviously user friendly. We were also impressed by its ability to plan secondary operations as well as our moulding presses and could see that its long and short term visibility would allow us to react in time to customer changes and provide accurate production dates.”

A decision was therefore made in 2004 to invest in Preactor and the initial implementation began with Preactor working closely with Tex. Once the initial software install had taken place, Tex’s IT department worked with Preactor staff to modify and create input and output files from the company’s database. This allowed Tex to import Works Orders and actual production output data into Preactor. Mr Sentance notes that the implementation went smoothly, adding “Preactor also provided an email and phone helpline ensuring any teething problems were addressed quickly and effectively.”

After a successful go-live, the most immediate benefit was the dramatic increase in visibility and accuracy of information across the entire planning process. “We could now manage resources and capacity much better” remarks Mr Sentance. He continues, “Not only could we see any problems before they occurred, we now had the flexibility and agility to respond to short terms changes in demand as well as any issues with a given resource. And because of this visibility, our customer service team could immediately update the customer which in turn has increased our customer service levels.”

The other key benefits Preactor has brought are substantial savings in both time and cost. Mr Sentance again, “Prior to Preactor, generating the weekly plan took the best part of 2-3 days. Now it’s 2-3 hours. Not only is this a direct time saving, it also means that this time can then be invested in further developing and refining the plan to generate even better planning efficiencies.” The ability to plan secondary constraints and operations has also saved time because the company can now accurately factor in for example accurate drying times for different products in-between operations as opposed to using approximations.

One notable cost saving is in the area of stock reduction, especially buffer stocks. “The increased accuracy and flexibility of the system means that we can safely manufacture certain products in house that we previously would have had to buy in” notes Sentence. In fact, there are some components Tex no longer even keeps. In terms of overall stock levels, he estimates that Preactor has helped reduced this by 30-40% with labour costs within the planning department having been reduced by an even more impressive 50%.

Looking to the future, Tex is currently investigating using Preactor viewers to display up to date planning information directly on the shop floor as well as ways to ‘close the loop’ in terms of feeding real time shop floor information back into the system so that the production plan is continually kept in real time. As for the system thus far, Mr Sentance concludes as follows. “The benefits we have achieved are exactly in line with the reasons we bought the system. We now have complete visibility across the entire plan – at the production floor level and also in Customer Services – and are making better use of our capacity by minimising our constraints.”