Ventilation Systems. Static ventilation systems

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1 Introduction Modern organization of production, especially as regards industrial production, considers environmental conditions at the workplace as a factor that affects production. mong these environmental conditions, ventilation is one of the basic elements that affect environmental quality and temperature. Therefore, the goals of industrial ventilation should be as follows: - To evacuate the heat produced by the production activity in order to maintain environmentally acceptable temperature conditions. - To renew air that is stale and contaminated by the exhaust produced by the industrial activity. - To evacuate smoke caused by the industrial activity, or fire, in which case this would constitute safety ventilation. Essentials of industrial ventilation Ventilation systems are based on the VENTURI effect, i.e., the fact that warmer air rises. ll ventilation systems take advantage of cooler air entering at lower elevations and warmer air being released to the outside at higher elevations. Hiansa s ventilation systems for industrial bays can be either static or forced ventilation (dynamic ventilation). Hiansa also makes smoke extractors.

2 Ventilation Systems Static ventilation systems This is also known as natural ventilation. The system is based on the entry of fresh air through fixed or adjustable slats located near the floor and air extraction at the top through static air vanes that use wind and changes in temperature and generate low and high pressure zones. This system is suitable for buildings that have high open spaces and generate internal heat, making natural ventilation efficient. The system should be adjusted to the extraction flow volume required. The air flow will depend on the volume of the living space, the comfort required and the activity performed within the building. Depending on the activity, air stratification can vary between 1 and 2 ºC per linear horizontal meter. Hiansa can provide static ventilation systems placed either individually or in a line. ll our systems are manufactured in galvanized, prelacquered sheets or stainless steel. They are all prepared to adapt to any type of roof and come with a manual closing mechanism and a bird-proof screen. Individual static ventilation s the name indicates, the warm air vents can be placed individually on the roof. The system is easy to install and simple to implement, regardless of the shape of the roof, because it is already prepared for that purpose. It features minimum maintenance requirements. It works by warm air depression and the Venturi effect. It impedes the entry of outside air. The installation does not require production down time. It prevents heat from accumulating. It can be adapted to any type of roof. It is especially recommended in warehouses. It can extract a range of flow volumes, depending on needs. Provided with a closing cover. Static system Model Height (mm) Weight (Kg) Neck (mm) Flow (m 3 /h) III VI VIII

3 Ventilation Systems Linear static ventilation The vents are placed in a line, depending on the roof guide (on the highest point of the bay). The bases of the vents have to be adapted to the roof slope and maintenance requires accessing their location, which is normally at a height of several meters. This is the most popular system because it can be adapted to any type of roof, and has low consumption and maintenance costs. C B daptable to any type of sheet metal and manufactured in various types of finishes: galvanized, prelacquered, aluzinc mm thick. Vent weight is 18 kg/meter for the HV-250 and 21 kg/meter for the HV-500. Type B C HV HV Thermal bridge / air renewal table Purpose of the bay or building Recommended temperature difference ºC Minimum Maximum ssembly plant, warehouse, sports center Manufacturing plant, welding, machine room Industrial processes with small furnaces Steelworks, ironworks, large furnaces Smelting furnaces, boiler rooms

4 EXTRCTION FLOWS Difference Diferencia de in temperature temperatura ctual ltura distance efectiva entre height Caudal Flan de extraction extracción flow por ml. between entre la air entrada entering between el nivel del the ventilador height per del linear ventilador meters en in m3/h m 3 /H y la and salida exiting del aire in of the y nivel fan and de entrada the height en degrees grados centigrade centígrados of the de air aire entry metros in meters HV HV Practical case: 1. Given the following bay dimensions: verage height (8 m), width (25 m) and length (50) m) Bay volume: 10,000 m 3 2. Identification of the activity to perform: ssembly plant, 6 renewals per hour. 3. Total air volume to renew per hour 10,000 x 6 = 60,000 m 3 /h 4. To choose the static vent to use, use the following data from the chart: With the desired temperature difference: 10 C ctual distance between vent height and air entry height: 7 m. The choice is Hiansa HV-500 vent with an extraction flow of 1,530 m 3 /h. 5. The linear meters of vent needed for the 50 m plant length are: 60,000 m 3 /h / 1,530 m 3 /h = 39.2 lm of HV-500 vents This example is a typical and practical case of natural ventilation, where there is no significant internal source of heat in the industrial bay. Were there to be such an internal heat source, high power ventilation would be required. Several parameters from the heat source would be used to calculate the extraction surface and to determine the number of fans and their type, as well as their location and the surface of ventilation blinds. ll this generates a framework of calculations that our Technical Department would be happy to assist with once the query is presented.

5 Ventilation Systems Dynamic ventilation systems The essentials and operating procedure of the dynamic ventilation system are exactly the same as those of the static ventilation systems, except that in this case the natural ventilation is backed up by motor-supplied power, whereupon its efficacy and working capacity does not depend on outside wind and is affected to a lesser degree by internal atmospheric pressure. The air is rapidly renewed so this system is especially recommended in activities that generate steam, dust or heat. Hiansa vents are supplied with remote controls, bird-proof screens and can provide a variety of extraction volumes, depending on requirements. Dynamic system Model Speed (rpm) Power (Kw) Neck (mm) Flow (m 3 /h) Noise level db () , , L , , L 970 0, , L 690 0, M , L 950 1, , M , Manufactured in galvanized, prelacquered sheets or stainless steel. Fasteners sized for any type of roof. Closing covers activated by overpressure and motorized. Explosion-proof motors on request. Various suction power levels, according to needs.

6 Ventilation blinds ir renewal requires the entry of cold air. If the ventilation is static, this entry must be 1.5 times the exit surface in m 2. 1 m 2 exit VS 1.5 m 2 entry surface The necessary entry of cold air is obtained by placing ventilation blinds, with either fixed or mobile slats, located on the facades of the building and that comply with the following conditions: Placement as near as possible to ground level. Placement should be regular along the entire facade, and the number will depend on the air renewal requirements. Placement on the various facades of the building. The calculation should not include the doors and windows on the facade. H H Système dynamique Model Speed (rpm) Power (Kw) Neck (mm) Flow (m 3 /h) Noise level db () , , L , Safety ventilation: Smoke extractors In the event of a fire in closed areas, smoke and gasses rise vertically from the source to the roof. The layer of smoke and gases can be prevented from affecting a larger area by appropriate installation of air entry and exit points in the proper places and sizes. This is the function that should be performed by smoke extractors to: llow staff to access the exits. llow firefighters to be more effective. Protect the installation as far as possible. Reduce combustion residue as far as possible. The cost of installation of extractors is quickly compensated by the significant reduction in fire insurance fees. Extractor operation is based on the location of vents with slats on the roof, as seen in the drawing. Note: Extractors can include polycarbonate slats to provide the bay with natural light. Manufacturing Footing: Manufactured in galvanized or lacquered sheeting. Perimeter: Manufactured in galvanized or lacquered sheeting. Slats: vailable in galvanized or lacquered sheet, polycarbonate or armored glass. Slat pivots: Manufactured in self-lubricated nylon (no maintenance). Slat sealing: To reduce heat loss and air filtering to a minimum, all the sides of the slats are equipped with a standard leakproof brush. Finishes: ccording to RL colors. Insulation: vailable (as an extra option). Optional accessories: Bird-proof screens, theft-proof safety bars, fuse protectors, framework finishes. Maintenance: Minimum maintenance. The control system must be checked periodically in compliance with the local, official or company regulations described for each installation B B Cross section Longitudinal section