Follow these 7 tips to be sure it was the best decision you will make to add to your existing glass machinery.
1. Space....be sure you have enough space. The average furnace is about 72 feet long by 5 to 8 feet wide. Don't forget about the blowers for which their can be as many as three depending on the thickness range. Do you have good height? If so think about putting one blower on top by building a mezzanine on top. This is particular good for saving space and is the solution for many when space is limited. However, thin glass takes more than one blower to quench and therefore you may need room for as many as two blowers. Be careful with this subject and be sure you measure very carefully.
2. Electricity......this is a big one and where most new comers to glass tempering in glass fabrication make their costliest mistakes. Adding tempering to your existing glass machinery and glass equipment means a substantial increase in power requirements. Most buildings were not built with such a large electrical capacity. Research this one carefully with you glass tempering supplier and your electricity supplier. Do not order your furnace until you are sure that you will have the power you need when the new glass machinery arrives.
3. Noise......are the neighbors close? Tempering Glass, especially when quenching thin glass, is loud. Big blowers work hard to get enough air on to the surface of the glass. Thin glass must be cooled very fast, especially 3.2 thickness and it is going to be loud. You can insulate, but if your in an area where sound levels are sensitive, beware as this could be a serious problem in getting started.
4. What type of furnace? This is a critical step in being sure you take your glass processing company in the right direction. Will you be tempering regular monolithic glass? Will you be tempering low -e soft coat glass? Years ago, most tempering furnaces were heated by radiant heat. With the new low e soft coated glass their grew the need for convection to be added as the top coat of glass has a reflective coating that will deflect top radiant heat back to the source and not absorb into the glass. The next level up is compressed air convection often referred to as "air assisted" or "semi convection", This way is using a big amount of compressed air. The newest technology is " full convection " using heating fans and not compressed air. Be careful here as some suppliers promote "semi convection" as "full convection" . If there is a need for a compressed air tank for the furnace heating chamber than it is not "full convection". Buyer beware!
5. Price? This is also a critical step as the prices of furnaces vary quite a bit. First think about your budget then determine your needs. When your decision is to temper below 4mm the cost will go up as you will require more blowing power for the quenching section. The difference can be substantial. The next impact on the price is based on the heating system. As you go up the ladder from basic radiant to full convection each step is significantly increase the cost.
6. Size? Another critical decision for your glass fabrication company. If your in the flat glass architectural business you will want to be sure the furnace is able to temper your medium range. Be sure not to go to small and never go to big. Be sure that you can get best yield from a charge and be sure your not buying an over sized power consumption monster. I have found the best range to be 72x 120 pr 144, 84 x 144 and 96 x 168 for standard custom flat glass fabricators. Many other sizes are available and some suppliers will customize the lengths to meet your requirements.
7. Furnace supplier? Be careful and know who exactly you are buying from. Be sure to check at least ten references, go see existing companies using the equipment and be sure to speak to owners, operators and maintenance people. Are you buying from a company has service, support and spare parts available when you need it? Be sure your buying from a reputable distributer that has a support team to help you through each phase of the buying cycle through installation and on going support once it is up and running. Be sure your bargain is really a bargain and not the most expensive mistake you will ever make! Don't jump to a bargain without knowing all the consequences. Be very carefully and this decision may lead to the best decision you could make for your glass fabrication facility.