Crowcon
Precision Manufacturing for Life-Saving Gas Detection
Precision Manufacturing forLife-Saving Gas Detection
One of the most serious hazards that workers in oil and gas, utilities, and manufacturing industries may be faced with is exposure to toxic or flammable gases, or to areas of oxygen deficiency. Because dangerous gases are often odourless and invisible, workers must rely on gas detection equipment to alert them if the environment they are in has become unsafe.
Crowcon Detection Instruments is an industry-leading designer, manufacturer, and supplier of gas detection equipment. Designed for use in demanding industrial environments, Crowcon’s devices provide workers with continuous monitoring and an early warning of hazardous conditions.
Crowcon launched the UnoIQ and DuoIQ personal gas detectors as part of its new IQ range. Both handheld products incorporate modular sensor technology which is designed to allow users to replace the pre-calibrated sensors within the devices quickly, while in the field.
Hymid's specialist injection moulding team partnered with Crowcon's product development team to help bring the new IQ range to market. As a successful manufacturer of other Crowcon products, Hymid was selected as a trusted development partner for their deep understanding of the performance, regulatory and manufacturing challenges involved.
The brief was complex and exacting. The housings had to protect sensitive gas detection technology operating in hazardous industrial environments, while meeting stringent certification requirements and surviving the rigours of daily field use. The design also incorporated interchangeable sensor modules that needed to fit and seal precisely throughout the product's operational life.
"From the first tooling sketch to final production parts, Hymid's obsession with quality showed in everything they did. They engineered the tool down to the finest detail, worked hand-in-hand with us on part geometries and ATEX requirements nobody else wanted to touch, and put every design change back through a full DFM review — no shortcuts, ever. That's the kind of partner you want on a two-shot program."
Josh Chen
Principal Design Engineer, Crowcon
The Challenge
The challenges presented by the project were many and multi-faceted. The enclosure for each device is considered a key part of the detector's design, not least because it protects the vital sensor technology contained within the unit. Both external enclosures had to be designed at the same time as the internal electronics and sensor equipment which they protected. From a regulatory perspective, the enclosures had to:
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Satisfy the requirements associated with ATEX, IECEx and CSA US certification
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Withstand a 6-metre drop test
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Operate across temperatures ranging from -20°C to +55°C
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Achieve IP66 and IP68 ingress protection ratings so that dust and water could not reach the detector's internal components
The ATEX regulation required the use of polymers that had some level of conductivity to dissipate any static in the enclosure. Polymers are naturally insulative to electrical current, which makes them a potential fire hazard when used in portable equipment, so Hymid’s team had to incorporate antistatic TPE within the outer shell to provide the required conductivity. These polymers are difficult to process in production so special gating had to be incorporated within the moulds in order to feed them into the tooling in the best possible condition.
The housings combined a strong, rigid substrate polymer, a clear polycarbonate for the LED display, an antistatic elastomer, a push button that activated tactile switches and light-refracting lenses for their LED alert systems. Collectively, these represent an engineering challenge that can only be overcome through the experience and knowledge Hymid’s team has built up over decades.
Each device comes with a series of modular, pre-calibrated sensor trays which can be swapped out by the user in minutes, quickly modifying the devices to recognise new or different gases without taking them offline or returning the detector for servicing.
Crowcon also wanted users to be able to replace these trays without specialist tools, however, that required the enclosure and each tray to perfectly match up and maintain a tight seal throughout the detector’s operational life. Even barely detectable dimensional changes within the mouldings could affect how easy the detectors were to assemble, or how the units perform when in service.
Crowcon's Principal Design Engineer, Josh Chen reflected on the engineering process saying, "Rather than telling us what couldn't be done, Hymid's team kept asking 'what if we tried this instead?' That collaborative mindset is what got a genuinely difficult two-shot part into production."
"Uno Duo IQ is a good example of what DFM should look like,
not a bolt-on review at the end, but part of the process from
early on. Working closely with Josh and the Crowcon team meant
we jumped those development hurdles before they tripped us
up."
Richard Lees
Design director, Hymid
The Solution
The plug-and-play modular approach (swapping sensor trays in and out) for Crowcon’s handheld devices was a significant product USP, and required a high level of manufacturing precision and component consistency in production. While Crowcon retained design authority throughout, setting the vision and defining the performance requirements, Hymid’s role was to translate Crowcon’s vision into a manufacturable product. A vital part of this was the input provided by Hymid’s team as early as the design concept stages of the project ensuring that any manufacturing constraints were clearly understood and incorporated into the design before tooling commenced. This collaboration continued throughout the DfM process and tooling trials to ensure that tolerances would be achieved consistently during production. Both organisations participated in regular technical reviews to assess trial data and resolve any issues as they emerged.
Delivering Crowcon's vision required a sophisticated two-shot injection moulding process, coupled with tight design tolerances that had to be consistently maintained throughout the production cycle. The two-shot process allowed the enclosure’s rigid substrate to be bonded with the softer elastomer overmould during one single moulding cycle, rather than in successive moulding cycles. This avoids any need for secondary assembly operations which can create dangerous leak paths.Moulding the devices in one operating cycle fully seals each product, helping to make them intrinsically safe.
Two-shot moulding is a complex procedure, requiring specialist tooling with precisely controlled process parameters and a deep knowledge of materials.It can only be delivered by manufacturers with a high level of engineering capability and discipline within the production process, both of which Hymid has developed over many years of operation. Even minor variation could affect sealing performance, assembly, regulatory compliance or the user experience, making consistency throughout the manufacturing process absolutely critical.
The devices’ interchangeable sensor trays had to fit precisely onto the main body of the enclosure to avoid any risk of leakage, requiring incredibly tight design tolerances and margins between the mating features and sealing surfaces. The trays needed to have parallel external walls, to align with Crowcon's design vision for the finished product.
To achieve this, Hymid's tooling team incorporated a series of wrap-around side actions (slides) within the moulds, together with internal lifters. These tooling features enabled the required geometry to be moulded without compromising the external finish or dimensional accuracy of the component.
The two stylish devices are the epitome of attractive and purposeful, modern industrial design. In recognition of this, both have been given the prestigious Red Dot Design Award.
benefits
The final production-ready enclosures meet all performance, durability, and ingress protection requirements for both the UnoIQ and the DuoIQ.It also supports the requirements associated with ATEX, IECEx and CSA US certification, and delivers easy, safe user functionality.
Its simple interface and modular product architecture enables field-serviceable sensor tray swapping and provides workers with immediate, life-saving protection against hazardous environments, while also reducing end-user downtime and total cost of ownership.
This has been delivered by a scalable UK manufacturing base which supports both UnoIQ and DuoIQ through shared tooling, which in turn reduces costs and shortens time to market.
In addition, using the same enclosure platform for both products reduced the number of unique components required within their manufacture.
Finally, using the two-shot injection moulding process meant that there was no requirement to assemble the enclosures’ separate components after production.
Hymid has once again demonstrated how its innovative approach evidences the strength of its strategic positioning as a sophisticated development partner to forward-thinking businesses, capable of delivering changes far beyond the role of a traditional manufacturer. "Hymid's quality bar is genuinely higher than the spec sheet. They'd flag cosmetic and dimensional issues we hadn't even called out as critical, because they simply wouldn't let a part leave that wasn't right" says Josh Chen.
