Success in the lean workplace is the result of everybody’s interests being met, but especially the operator and their workstation.
After the production advances of Henry Ford, Toyota, GE and the evolution of practices like Kaizen, Kanban, 6 Sigma, Lean manufacturing, 5s, Visual management, SMED,
PQR and others, the correct balance between serving customers, worker’s needs and corporate responsibilities is finally being approached.
But who comes first?
Without the customer there is no business. Without workers no production and without profit no corporation.
In a true lean operation every process of business is scrutinised to increase efficiencies and reduce costs and errors so that the customer benefits from a waste-free operation and does not bare unnecessary production costs (re-working, excessive inventory, set up times, inefficiencies of space, excessive production transport and so on).
Less is more
Efficiencies developed as part of this lean approach, particularly in the production environment, consider the operator and task for every stage of the manufacturing process. These efficiencies are reflected not only in increased productivity and profitability, but also worker satisfaction and health.
At the core of an operator-driven process is the workstation or task centre. No longer considered furniture, the modern workstation is a tool designed to fit around the operator, their tasks and workflow. Even in these automated times a skilled operator/technician is a valuable asset to be looked after on many levels, particularly their physical and motivational requirements.
The AME system
In the production environment a successful workstation design will encompass aesthetics, modularity and ergonomics. It can be installed efficiently (ideally without locking tools) be visually open, make use of vertical space, leave a small footprint and be reconfigured quickly.
The customised design of a successful workstation is the result of examining purpose and function (required tasks) and fitting the physical attributes of the operator to the station and tasks. In a production context, components will be assembled efficiently, just in time and get to market faster.
The physical dimensions of the operator are taken into account with adjustments made to the chair, footrest and workbench for optimum posture and muscular skeletal support.
Because cumulative pressure on the lower back (lumbar region) often leads to injury, any provision in the design to relieve and prevent this by a choice to sit or stand while tasking, is preferable. In fact preventative measures are paramount in any workstation design.
It is advisable to also allow the height to be independently adjusted, in some cases electrically.
Height adjustability, especially the capacity to sit or stand while working prevents blood pooling by enhancing blood flow through the body and greater oxygenation. This leads to less fatigue, improved concentration, increased productivity, better safety, added satisfaction and more motivation.
Reach and grab
Each operator has an arc of work where point-of-use parts are stored and selected and components assembled. The maximum reach should be 630mm, for two hands
570mm; the optimum grab area is 300mm. Often-used tools, and gravity-fed parts containers, tool trolleys, racks and shelves within reach of the arc is needed so there is little or no stretching or lifting.
It is desirable to have tasks carried out below the shoulder and heart. Tasks above these points reduce blood circulation.
This planning will greatly reduce body and arm twists, excessive wrist flexing and repeat motion injuries. It will also increase productivity.
Also, when elbows and wrists are supported, strain is removed from the trapezoid muscles, across the back between the shoulders.
Seeing is believing
An operator’s vision is best focused on tasks that do not require much downward or upward gaze, head or neck rotation or refocusing. Optimally AME System aims to keep the view angle to less than 35°.
Ideally any monitors at a station should be flat screen (which take less visual space) and should be affixed to a swing arm to adjust the monitor angle to the correct eye level of viewing.
Non-glare, shadow free lighting is best, spread evenly over the assembly area. There are benefits to fluorescent, halogen and LED (light emitting diode) lighting. LED has the advantage of being solid-state, cool burning, long lasting, energy saving, and which provides a colour wash to the work surface.
Isolate and integrate
A wholistically designed workstation that also fulfils the lean process criteria is best integrated with an overall lean production strategy.
Best practice manufacturing will seek to be constantly improving. Much is owed to the Japanese for their embodiment of this in the kaizen attitude. A key component of this is the Visual Factory Workplace (VFW) where a skilled manager or consultant will quickly ascertain the leanness of the workflow layout.
Construction of the workstation will reflect this philosophy with its narrow unimpeding columns and openness.
VFW incorporates the 5S principle as well; sorting components; setting in order –identifying and arranging everything; shining – regular cleaning and maintenance of an area; standardise procedures and sustain – maintaining what has been accomplished.
Supporting an operator’s workflow should involve a timely supply of components, parts and supplies so that they have what they need where they need it and when in response to customer demand. This is often referred to as Kanban and incorporates the pull principle.
May theories have developed over the years in support of better production processes and overall lean manufacturing management. Those that combine to offer a total approach and which respect all the stakeholders, especially the worker, will benefit the most.
AME System is a designer and manufacturer of ergonomic workstations for assembly production across biotechnology, automotive, engineering and gaming industries.