Sweeping changes at Johnston

Posted on 8 Sep 2009 by The Manufacturer

It stands to reason that Johnston Sweepers, a company which specialises in street sweepers, should have an extremely tidy and organised manufacturing structure. Tim Brown talks to marketing director, Steve Douglas, and operations director, David Bishop, about the business’s modular operation.

By focusing on its customers, employees and the environment, Johnston Sweepers has implemented an extremely effective continuous improvement and investment policy. The end result is an efficient production process which focuses on the unrelenting pursuit of quality as its primary aim. To achieve this objective, Johnston Sweepers have implemented a raft of different strategies, together with the areas of customer service and quality having been combined so that customer requirements can be relayed to the factory as quickly as possible.

At any one time, Johnston may have up to 90 staff working on continuous improvement projects at its three manufacturing sites. According to operations director, David Bishop: “We’ve sent in excess of 20 people away on problem solving courses, lean problem solving or Lean facilitator training, which is delivered by the likes of EEF and MAS – those people then assist with our continuous improvement projects. The projects that we work on are selected if there is a customer problem or management identifies that the process isn’t flowing. We have found that the continuous improvement projects are self-perpetuating, for often as the team rectify one problem they may uncover another area that could be improved.”

This commitment to quality and efficiency truly emerged in 2004, when Johnston Sweepers re-launched its entire range as one modular group of machines. The result was a remarkable decrease in parts, which included reducing the number of sweeper bodies from 120 to six, the number of auxiliary fuel tanks from 23 to one, and the number of rear doors from 114 to two. Not surprisingly the result, according to Bishop, was a large increase in efficiency in all areas of the business.

“On the selling side, it gave us better control over our price lists and definition of the product,” he says. “We integrated the sales end through a configuration system so that the salesman effectively constructs the bill of material from pre-engineered modules. It gave us administrative efficiency as well as manufacturing efficiency. Whilst we were making the same number of products there were far fewer part numbers.

Instead of managing individual batches going through the factory, we were able to start looking at the flow of materials from purchase order to sales invoice.”

While the company still builds to order, it has moved away from constructing individual specialised sweepers, with the only true area of on line customisation now required being the colour scheme for the vehicle. The more streamlined process has revolutionised and benefited the entire business.

“As a result of launching a more modular product,” says Bishop, “we were able to, in both the Sittingbourne and Dorking factories, introduce flow production. Previously two employees would take a chassis and build an individual sweeper from start to finish. Now we have a six stage flow line through which the product moves so the sequence, the method and standard of build is common to every machine and it is also easier to predict when a machine will be finished. This has significantly reduced our build time, which for instance on the truck mounted sweepers has fallen from in excess of 120 hours down to 60. We have experienced similar savings for our other products as well.”

Customer benefits
The streamlining of the company processes has also provided Johnston Sweepers with the ability to be flexible and responsive to customer demands. “We believe that our throughput time is much faster than any of our competitors,” says marketing director, Steve Douglas. “Delivery and lead time is made up of two elements – the cycle time in the factory and the size of the order book. However we have, over the last couple of years, been able to take a number of orders with short lead times and successfully deliver on them. Our sales volume is not a high number due to the size of the market. We currently produce up to 25 units per week, but if a customer comes in and wants 20 delivered in three weeks, we’re usually able to do it.”

The improvement in efficiency has also allowed Johnston to pass on other benefits to customers including a low cost of ownership. In fact not only are maintenance costs low but purchase costs are also extremely fair. “The material costs of our products are aggressively challenged and as a result product costs have been controlled, says Douglas. We’ve been able to grow our export turnover by 40% due in large part to the internal efficiency improvements we’ve undertaken.”

Environmental considerations
Johnston is the first Sweeper company to achieve ISO 14001, which reflects its commitment to sustainability. In cooperation with the Carbon Trust and NIFES Consulting Group, Johnston carried out an opportunities assessment survey to identify and prioritise actions to reduce carbon emissions. Even the simplest of measures such as the installation of new doors at the Dorking and Sittingbourne sites, which only open when a vehicle is approaching, have already reduced their gas bill by 17.5%. With all the suggested measures now implemented, the combined savings from these changes represent a 14.2% reduction in energy consumption and a 10.6% reduction in costs.

The vast changes that were implemented ranged from the replacement of lights to the optimisation of equipment for combustion efficiency and even the implementation of video conferencing to reduce the carbon output from travel. However, Johnston have also undertaken broader changes to decrease its environmental impact, including the use of more environmentally friendly paints, the use of chlorine free cutting oil, and the implementation of a comprehensive recycling policy. These environmental improvements have not just been limited to the Johnston manufacturing process either, with environmental considerations also being applied to its products. For instance, the C200 sweeper saves up to 40% on fuel consumption when compared to other sweepers in its class and both the V range and Compact range both meeting the latest emissions standards.

Despite the current economic climate, over the past 6 months Johnston has forged ahead with a raft of different investments in IT and plant and facility infrastructure. A new in-line shot blast machine and powder coating plant has been recently installed at the Dorking site. Instead of the current zinc phosphate which is a potential hazard to the environment, the new powder coating plant will use oxsilan, a synthetic which uses far safer nano technology. The new process also gets rid of the current phosphoric acid, using the more environmentally friendly citric acid alternative. Components are now sprayed, rather than dipped and only need to hang once. To achieve a high level of finish, a shot blaster unit was required and following a highly complex renovation process, the machinery was successfully installed and has provided excellent results.

Another significant investment was the installation in January of a brand new Motoman robotic welding cell. Designed in Japan, built in Sweden and tested in Banbury, the actual tooling for the parts which it welds have all been designed and built in-house at Dorking. The new cell will be used to make sub-frames and rear doors, and has dramatically reduced welding set-up time from one hour down to twenty minutes.

However, the single biggest project ever undertaken by Johnston was the introduction of SAP software, the implementation of which involved literally thousands of hours of work. On Sunday 1st March this year, the new SAP system went live. Everything possible was done in advance to make the switchover as smooth as possible and the undertaking has proved very successful, moving the company to another level of integration.

Despite having already achieved considerable progress, the company will not be resting on its laurels and will undoubtedly stay the course ensuring consistent continual improvements. With a company culture which promotes inclusion and lateral thinking among employees, achieving further benchmarks in efficiency are only a matter of time.