You think you know just-in-time? Johnson Controls in Sunderland must deliver correct seat variants to neighbour Nissan in precisely the right order, 170,000 times a year, where errors are not tolerated. Operations manager Neil Fairley shows Will Stirling the meaning of JIT manufacturing.
Nissan Motor Manufacturing UK produced over 448,000 cars in the 2010 financial year, and is about as lean as any manufacturing system in the world. Component parts need to arrive in narrow windows, there is no margin for error. The best way to achieve that? Build the component factory right next door and develop a fully synchronised production system.
That’s what Johnson Controls did in 1984. The US engineering group originally had a joint venture here with Ikeda Busan, called Ikeda Hoover, located next to Nissan’s 800-acre site, before Johnson Controls Inc (JCI) bought out the company in 2001. The company manufactures automotive seating in a full-seat kit – two front seats, a rear cushion and a 60/40 split seat – and supplies to one customer, Nissan, for two models, the Note and the superpopular Juke. It’s a long established, symbiotic relationship which demands ultra-accurate delivery schedules and zero defects to fulfil customer needs. Touring the factory with operations manager Neil Fairley, the watertight operation is a window into what UK factories have to do to retain business in today’s fiercely competitive global automotive market.
“To hit the tough quality target, we are only allowed two defects per month in the entire delivery of 170,000 seat sets per year to Nissan. It’s extremely challenging,” says Mr Fairley, a six Sigma Black Belt with 12-years service at the Sunderland site. “Quality is very focused in this plant.” Johnson Controls has competitors and big seating contracts for UK-based carmakers do exchange hands. Each contract is vital and Nissan UK – manufacturing about 136,000 Jukes and 40,000 Notes per year – waits for no-one, so it is essential to hit key performance indicators (KPIs) as close as possible, all of the time (see box).
To achieve such razor thin delivery and quality requirements, in 1984 Ikeda Hoover developed synchronous supply with Nissan. Today, this is a finely tuned machine based on a four-stage parts ordering process. This is honed down to real-time data, the synchronous broadcast, which arrives via EDI transfer to printer stations around the factory.
“When a vehicle comes out of Nissan’s paint shop, we receive the synchronous broadcast as live data,” says Mr Fairley. “From receipt of the broadcast to seats fitted in the vehicle at Nissan, we have 2.5 hours. We are truly just-in-time.”
Johnson Controls Inc is split into three separate divisions – Automotive Experience, Building Efficiency (building management and air conditioning) and Batteries. Automotive has four satellite assembly, or JIT plants, in the UK. The Sunderland site looks after Nissan, Burton near Derby serves Toyota, Halewood serves Jaguar Land Rover and Ellesmere Port supplies to GM.
Sunderland used to be a fully integrated plant. “Now big automotive suppliers tend to have business units in Centres of Excellence, for example foam manufacture and metal parts, with assembly or JIT (just-in-time) plants right next to the customers.” This plant still has a metal welding department, mainly operating robot welding for the Note seat frames.
Sunderland is unique in the UK in having its own design office. “We’re lucky to have it. If we have any questions about design programmes for models we can ask on site,” says Fairley.
Synchronising production with demand is at the heart of all manufacturing. At Sunderland, it has been perfected into a science. There are four stages:
- Plant receives forecasted volumes over six months from Nissan.
- A 15-day forecast provides more firm data.
- CAT 3 – three-day data, as accurate as possible.
- Real-time synchronous broadcast from Nissan.
This data-driven system is designed primarily to guarantee the customer receives the correct seat variants at the precise time. It also eliminates stock, saving space and working capital.
Sub-components like the welded frames of the Nissan Note are manufactured from CAT 3 data. “But for the seat manufacture we can only build to broadcast, otherwise we would need to keep a lot of stock,” says Fairley. “We have zero work-in-progress for seats and zero finished goods.
An order comes in for manufacture and it goes out straight away. We have just that 2.5 hour window within Nissan.” In volume terms, Sunderland has about 80 sets of seats between the picking stage, on receipt of broadcast, and the point-of-fit in Nissan. Current line speed is 50 sets per hour, or about 1.5 hours worth of stock in the line. The completed seats arrive at Nissan not only just-in-time, but customised to order because there are several seat variants.
“Synchronous means one vehicle could be a Note, the next a Juke, the next two a right hand drive Note, etcetera,” says Fairley. “Seats are delivered to the Nissan point of fit as a perfect reflection of what vehicles are being finished there. Therefore it’s crucial we receive the Broadcast after it leaves the paint shop; there are no faults, no issues, that vehicle will definitely be finished.”
Fusion of labour and automation
On the factory floor, crews of Manufacturing Team Members (MTMs) work flat out. Every operator knows his job. The Juke line is a seamless picture of synchronising man and machine to make the precise product variant on time. The term Standardised Work is a mantra at JCI, says Fairley. “Every operation has an operator’s description sheet, for how to complete a job within strict parameters. This minimises the chance of making defective products.”
It’s clear that the plant is lean in practice, and theory. KPI boards – updated weekly with metrics like Customer PPM (product delivered to the customer), Internal PPM (product post-assembly line that needs rework or repair), Build schedule, Zero defect days, the JCMS radar chart, etc – are posted in each department. Stations where seat kits are kitted are linked to the assembly line by an automated guidance cart, operated by a magnetic strip, which removes non-value added labour.
Small parts are replenished at stations continuously. For larger parts such as trim, a satellite printer also receives the broadcast to eliminate unnecessary walking to read a single broadcast. Sunderland has developed its own kanban. When large part boxes need replenishing, the operator moves a card from below to above the red line, and a flag is raised. “This ticket system tells the fulfilment operator what, how much and where to get the part from, saving time from random checking.”
Several innovations have been implemented to fine-tune the man/ machine interface. Small Parts Centres, kits of small parts like fasteners, have been raised to the optimum hand level to reduce bending. Work stations are ergonomically designed for a person of average height. There are simple visual management aids, like clear water bottles so that team leaders can check no coloured liquid is near the line.
Because standardisation is so important, Sunderland introduced the Shop Floor Control System. At the point where a seat is fastened to the frame, the number of fastens, the torque strength and angle of torque of each fasten is fixed. Operators use a DC control wrench fitted to the Shop Floor Control System, which prevents the seat from being released until the correct number, power and angle of torques on all fastenings are correct. More recently, all data associated with any Juke seat made is captured on an internal server, so any defects can be traced back.
Rear seats are assembled separately, but both front and rear seats are built in the same product sequence, based on the broadcast. For inspection and despatch, for the last three years Sunderland has used a robot to lift finished seats at the inspection station, and put on a dispatch pallet. This saves unnecessary manual lifting and is more efficient.
As part of a continuous improvement programme, the new Note assembly line will feature overhead lights on every station, both manufacturing and inspection, making it easier to stop a defect before it passes on to the next station.
Seats are shipped in magazines of 24-seat sets, where each set mirrors precisely the car variant being finished at Nissan. Loading for dispatch and unloading at Nissan is fully automatic and the broadcast ticket follows the product throughout.
People and training
The plant constantly measures value added and non-value added analysis, including line balance reviews. “MTM data tells us how much time operators should spend on each station as a benchmark,” says Fairley. “In the climate we’re in, there’s no more money to burn. We have to ensure that what we budget for in manning and cost is achieved. The way to do that is monitor our manning – can we move any non-value adding aspect of that?” All new MTMs are trained in the nine modules of the Johnson Controls Manufacturing System, or JCMS, within 12-months of joining the company.
JCMS is a proprietary toolbox that covers the core principles of lean, including 5S, problem-solving, VSM, culture and awareness, and quick tooling and die changeovers. And 5S score cards between departments are published in league tables to spur some internal competition.
Loyalty is important at Sunderland. “The plant regularly has recognition events where we reward long servers. We’ve got people who’ve been employed since it opened almost 25-years ago,” says Fairley. This extends to management. Johnson Controls’ European General Manager for JIT used to be a team leader in the Sunderland factory and several production managers have been with Sunderland for 20-years.
Investment here is also supersynchronised with the customer. JIT sites benefit from a five to six year investment programme that begins before a customer launches a new model. Juke was very good news for the site, which was suffering from reduced volumes. “It was very fortunate that we landed the Juke contract in midrecession,” says engineering manager Paul Swainston. “It coincided with the automotive industry slump, at a time when the company was trying to minimise spending.”
Seat manufacture is a labour-intensive process. Rather than invest in capital machinery, most investment at the JIT sites has been to automate processes to reduce human ergonomics and low value-add activity. Part of this is the Shop Floor Control System, but Sunderland has also introduced a visual management tool called Strike Zone, adapted from a popular Japanese method designed to reduce avoidable bending and lifting plant-wide.
Looking ahead, Sunderland plans to adapt the Note ‘TEM 10’ cells, where seat trim is bonded to foam (they’re compressed to the seat in 10 seconds). The plant plans to decommission them to free-up floor space. Mr Swainston says it is also investing more into quality control and process repeatability, and to make Strike Zone an effective philosophy that bears return on investment. “Strike Zone provides an efficiency gain, but it is mainly for ergonomics. Health and safety has always been paramount here.”
Johnson Controls Sunderland is a very tight ship, an exemplar of just-in-time manufacturing. Manufacture and delivery to a customer within 2.5 hours of order demonstrates just how lean plants need to be in today’s automotive industry if OEMs and their suppliers can survive, and thrive, in the UK.