install a fume extraction system

Location of fume extraction unit, indoor or out..? Outdoor unit Typical booth layout showing duct location...? Location of duct work will be as mentioned above the welding booths Does the unit require compressed air and if so can we connect in the drop located on the wall behind booths..? yes Duct work layout and size..? The system should be designed for having all 12 arms in use at once, with an airflow of approx 675-700cfm each Has the consultant specified the exhaust airflow (Cfm) that he wants in each booth? The system should be designed for having all 12 arms in use at once, with an airflow of approx 675-700cfm each Has the engineer specified the diameter of the exhaust duct in each booth? The system should be designed for having all 12 arms in use at once, with an airflow of approx 675-700cfm each What Air to Cloth ratio does the engineer want to use in the collector? There is no specification for the Air to Cloth ratio for use in the collector Does the engineer want to use HEPA filters before exhausting the air outside? No Does the engineer want to consider a gas fired air make-up unit to provide replacement air? No Will the service equipment be mounted in the shop area and where is the desired location. If referring to fume extraction, the equipment will be installed outside In the bid package on the extent of work page question #5 states "install service feed for extra 20 amp circuits on the opposite side of building" could we get more specifics on this? This is referring to the other side of the building that is planned for an additional welding fabrication classroom in the future. Statement #8 on same page "Install all electrical outlets needed for shop operation" also needs to be more specific. This is for the 12 booths What kind of plug configuration are the welders? 480 three phase Can we use an Amtech 12 cartridge fume collector with reverse pulse cleaning technology? No, not familiar with unit Confirm Unit will be located outside in the area discussed at the meeting? Yes unit is to be outside as mentioned in walk-through What diameter and length are the arms. As mentioned, the diameter will be proportional to exhaust fan. The system should be designed for having all 12 arms in use at once, with an airflow of approx 675-700cfm each The length must be at least 18 inches long enough for students to manipulate the arm easily within the welding booth. Electrical installation and connection by others. Yes, electrical and fume extraction installation are separate What is the capability of the compressor? SCFM @ what PSI? (Dust collector requires 5 SCFM @ 90 PSI) Two stage compressor; 5 HP, 120 Gallon; 17 CFM Who supplies the combination motor starter disconnect? Vender Can we use round duct instead of rectangular duct? (less static loss with round) Yes What is maximum noise level in dBA? Lowest dBA possible Is there a specified CFM requirement? The system should be designed for having all 12 arms in use at once, with an airflow of approx 675-700cfm each Shall we provide enough exhaust air to operate all the booths at any one time. Or will there be a diversity factor that only 75% of the boothes will be operating at any one time. The system should be designed for having all 12 arms in use at once, with an airflow of approx 675-700cfm each What total airflow at what esp shall we figure the collector and what square footage of the filter media should we provide. What shall the media be made of? The system should be designed for having all 12 arms in use at once, with an airflow of approx 675-700cfm each Filter media Do you want a spark extractor prior to the collector? yes What ampacity are the 480 volt 3 phase welder circuits supposed to be? 30 amp What ampacity and phase are the 480 volt machine tool circuits supposed to be? band saw 27 amp three phase drill press 27 amp three phase iron worker 27 amp three phase Does the grinding booth need (5) 208 volt circuits and (5) 120 volt circuits? No, there will only be two grinding booths two 120 Are the 208 volt circuits single phase or three phase? Prefer three phase How many circuits are required for the extraction unit and what voltage, ampacity, and phase are these circuits? One per booth, 120 volt for each booth and 480 three Where are the new panel boards and transformer to be located in the building? Loft may be a possibility As recommended by electrician Is a bid bond required for this bid? No bond is required. Is the electrical contractor responsible for all electrical work to new fume extraction system? Yes Will the exhaust ductwork be supported from the building structure above the welding booths, or supported from the floor? From the building structure above the welding booths Will make up air be required for the new exhaust system? No If the new extraction unit is set outside the building, will an air silencer be required for the exhaust air due to the noise level that may interfere with the surrounding class rooms? No Where will the 12 total extraction arms need to be mounted? This needs to be pre-determined because of the cost factor involved. Extension arms will be mounted above the welding booth and should extend at least 18". Will the mechanical and electrical be separate, or be combined together as one quote? Yes separate Which standard is to be used for duct fabrication, SMACNA HVAC duct construction standards etc. Galvanized industrial standard How do we review the responses to questions that have been submitted? On the Federal Business Opportunity website. Can the fume Extraction system be made individual for each booth eliminating the need for outside unit? No Variable air flow per booth is needed with shut-on/off for each booth? Yes Because you are enclosing each booth would there not be a need for lighting? No What filtration are you looking for is it just particulate (and to what level or eff.) or do you need vapor and gas filtration as well? on the grinding tables how many are needed.? Not needed for grinding tables Can the grinding tables be made with a dust collector built-into it. on the grinding table they need a down draft air flow? What filtration level is required for this application? No filtration for grinding tables nor airflow needed Grinding tables are to be portable? YES/NO? Yes The Grinding table will need lighting? Yes