Netherlands-based Promolding recently challenged UK firm Connect 2 Cleanrooms (C2C) to provide an intelligent cleanroom solution to protect a medical device manufacturing contract that is due to run until 2032.
Effective contamination control is critical, as Promolding is producing optical manifolds for an eye surgery machine. Designed to keep pressure on an eye during surgery when the eye lens is removed, these precision parts feature intricate veins and diaphragms.
Over nine months, they collaboratively developed a reliable and intelligent cleanroom solution, which works in harmony with Promolding’s Engel machines and robots.
The cleanroom is now safeguarding a long term investment, so design features have been optimised to guarantee cleanroom performance for years to come
The process
- One shot injection moulding machine (80 tonne) produces one plastics component
- Two shot injection moulding machine (300 tonne) produces the second component, made up of two plastics (injected, rotated then injected again)
- Robots pick up moulded parts, drop them onto the motorised conveyor and transport them into the main environment
- The two parts are then assembled and welded, then they progress to packaging
The solution
Each moulding machine has one fixed and one actuated, HEPA filtered, overhead canopy.
The automated, sliding HEPA-lite canopies provide overhead access for tool changes. They are driven by an actuator with two linear guides, one master and one slave. These drive the filter system to an open or closed position.
The canopies feature effective safety mechanisms, sending infra-red signals across the actuators. If the signals are interrupted, for instance by the robot or by operative’s hands, the canopy will deactivate movement, preventing any accidents.
The canopies feed into the main cleanroom area, which houses assembly, the plastic welder and packaging.
Industry 4.0
Industry 4.0 is the fourth industrial revolution - the digital transformation. It is a term used to cover the use of automation, smart factories, digital systems, sensors and robotics, data and remote operations - with the goal of increasing manufacturing productivity, improving planning and forecasting, or giving a competitive edge.
Here, C2C applied Industry 4.0 techniques and designed a cleanroom with automated canopies to work in cooperation with Promolding’s robotics. These reduce the risk of human error and improve the quality and consistency of the end product.
The cleanroom features an intelligent digital system, in the form of C2C’s ECO control system. It is designed to ensure that the cleanroom operates at optimum effectiveness by constantly monitoring the operating conditions, in real time within the critical environment, raising alarms if any of these parameters vary beyond a user specified threshold.
All relevant control parameters for each three zones are graphically displayed on a HMI touch screen interface, allowing users full control and to locate faults and run diagnostics. All system performance data is logged and is downloadable.
The intelligent moulding machine recognises faults with a product and drops affected products into stainless steel drop drawers for inspection. The personnel door is interlocked with the moulding machine during manufacture. The sample drawers are accessible from outside the HEPA-lite, meaning the faulty parts or samples can be safely removed without interrupting manufacture.
There are plans to have all the processes within the main cleanroom area to be fully automated in the future.
The main cleanroom area was installed under a mezzanine, so the ceiling was fixed to the walkway above it and suspended via 56 drop rods. This secured the roof and ensured that no internal legs were needed to support the room keeping an open plan layout.
C2C worked with a structural engineer, to develop the structural system. The four existing pillars supporting the building were used to feed the cleanroom’s utilities - i.e. sockets, compressed air.
The HEPA-lite canopy system and main cleanroom area have been designed to accept two more injection moulding machines to feed into the main cleanroom as demand grows.
There was an effective collaboration with ENGEL allowing C2C to integrate the HEPA-lite with the injection moulding machines, so it wasn’t necessary to use floor supports.
Support legs would have obstructed access compartments and the regular re-calibrations, so full access to the machine is hugely beneficial. Rubber mounts were used to absorb movement, so it doesn’t affect the canopy.
Despite being a precision build, the main room was constructed in four weeks and the HEPA-lite canopies were constructed in two weeks.
- ISO 14644-1:2015 Class 7
- Overall footprint: 279.42m² (19.27m x 14.5m x 2.825m). Internal clearance of 2.5m
- Internal change area: 13.86m² (6.860m x 2.02m)
- 99no. air changes per hour at an air speed of 0.45m/s in the Main Area
- 70no. 20W LED light fittings (6500K light temperature) to match the current lighting used within Promolding’s building
- 42no. variable speed controlled HEPA ceiling fan filters
- 4no. transaction drawers next to conveyor inlets
- 1no. roller door for goods in/out
- ECO Control System with automated sliding hatches on HEPA-lite units
- 2no. automated HEPA-lite canopies to supply clean air at the critical point of production and reduce contamination by significantly limiting exposure to the external environment during tooling changes.
- The cleanrooms which house the ENGEL machines and HEPA-lite canopies are 4.7m in height.
- The grey lid to the filter system houses cables, providing a cleanable surface and looks in keeping with the factory
- Pendant stations control each automated HEPA-lite on the injection moulding machines. Each have manual overrides for safety reasons
- Proximity switches to the side of the HEPA-lite have LED lights to give a visual indication when the HEPA-lite canopies are in situ. The canopies also feature a safety mechanism which deactivates actuators if the canopy is obstructed
Connect 2 Cleanrooms is exhibiting on stand D6 at Med-Tech Innovation Expo.
