Hans and his colleague make glass instruments such as storage vessels, tubes for chemical reactions, and columns to heat and separate liquids. Each instrument is specially designed to meet a specific technical problem.
“One of my most memorable jobs was making a part for a Shell naphtha cracker plant in India,” says Hans. “The piece was an intricate network of capillary glass. Each capillary had an inner diameter of 1 mm and had to be welded at a temperature of 2,500 degrees Celsius.”
Another challenging job Hans recalls is a reactor he made for a Shell carbon capture pilot plant in the Netherlands. The reactor was a glass vessel 70 cm (28 inches) long and 30 cm (12 inches) wide. It sounds simple enough, but it contains three walls of thick glass with other glass sections welded within it. “One company asked to fabricate this vessel said it was impossible!” says Hans.
In both cases the advantage of using glass instead of metal or plastic is its transparency. The user can see precisely at which point in the instrument blockages are forming and how best to remove them.
On average, it takes three to four weeks to design and make a glass instrument.
5 steps to a unique glass instrument:
1. Customer sends rough sketch or description.
2. Hans creates an initial 3D design using computer software.
3. The design is agreed with the customer.
4. Hans uses his glassblowing skills to make the instrument.
5. The instrument is exposed to chemicals, extreme heat and pressure for testing.
Glassblowing is craftsmanship of the highest order. It is also extremely demanding. One mistake or millimetre error could ruin several days or even weeks of work.
“Stress is your worst enemy,” says Hans. “If you are too hasty and don’t let the glass heat up slowly, it will break and you will have to start all over again.”
Now aged 28, Hans spent four years learning his craft at an instrument-makers school in the Netherlands. He joined Shell as a glassblower eight years ago, and has just bought his own torch to make glass figurines at home.
“When I left school I thought I was a good glassblower, but when I joined Shell I realised I was just a beginner,” he says. “Glass is a constant challenge with many secrets, and it takes a lifetime to slowly unlock them.”