Minutes of the Nelson/Marlborough BRANCH TRAINING AND NETWORKING EVENT
Held on 20th September 2017 at 3.00pm
At Viridian Glass Factory,
9 Tokomaru Place, Stoke)
Welcome:
The group gathered in the reception and display gallery area of the Viridian building where they were introduced to guide Tim Stoney. After a safety briefing, they were issued Hi Viz jackets and safety goggles before entering the factory.
Attendance:
Mark Hunter, NCC, Don Frame, House Care Ltd, Paul Farrar, PFBC, Allan Matheson, Helen Lawton, Robyn Edwards, Phil Beck, TDC, Paul Guile, MDC
Apologies:
Chris Wood, NCC, Bill East, MDC
Site Visit, Viridian Factory
The tour began in the office area where the design takes place. The desk top computers are connected to the machinery in the factory, as well as other Viridian factories around the country.
The first part of the factory was the cutting area, where two flat table cutting machines operate, able to cut sheets up to 3.6x2.4. The sheets of glass are brought in from a caged off storage area within the factory, which is only accessible by entry of an access code. The glass within the storage cage sits near vertically in steel frames. The sheets of glass are handled by large frames equipped with suction cups. These occasionally fail which results in the glass shattering on the concrete floor.
Once on the cutting beds, the glass is scored by the machine controlled tungsten wheel, to the patterns designed by computer and in such a way as to minimise the wastage. The scored sheet of glass is fed through to another table where it is manually snapped along the scored lines.
The next step is to tidy the glass edges, which is done by a vertical machine. The glass is fed in one end, travels through an edge grinding stage, then through a hot wash after which it is visually checked for defects. From there it is either dispatched to the joinery factory, or progresses to the double glazing stage.
The double glazing phase begins with the cutting of a hollow aluminium moulding. This is bonded to one glass pane and the other pane squeezed in place until the bond is set. The aluminium moulding is then filled with a desiccant which removes any moisture trapped between the panes. This is followed by a double sealing process that should prevent moisture ingress and the escape of argon gas (if this has been specified for the particular product being manufactured). The factory is capable of producing triple and quadruple glazed panels.
Next, we were shown the furnace. This is used to heat temper glass and can handle sheets up to 5.2 metres in length. The tempering process involves heating the sheet to 600 degrees Celsius (close to melting point), then rapidly cooling it with cool air pumps. This process takes only 4 minutes, from which it can be deduced that this machine consumes lots of electricity. Tempered glass can be identified visually using polarized glasses which show up the “oily” colours in the glass.
Glass is sourced from a number of countries around the world, and each location’s sands produce glass with different properties or appearance. The majority of our glass comes from Australia. Chinese glass is generally of poorer quality and contains more impurities.
Following the factory tour, we adjourned to the board room where, after consuming some very nice savouries courtesy of Viridian, we were shown a presentation on changes to NZS4223 corresponding with amendment 15 to B1. These, on the main, correct omissions in the previous version of the regulations which did not specify strength requirements for handrails and the maximum length of glass panels. We were also shown testing methods for measuring the rigidity of various barrier systems.
The site visit finished a little before 5pm and there was no time to hold a meeting.
**Refreshments kindly provided by Viridian Glass
Paul Guile
Nelson Marlborough Branch Secretary
paul.guile@marlborough.govt.nz
