Types of torches in the modern domestic market the large quantity is presented. It seems, among this variety it is possible to find without effort that option which will arrange according to all characteristics. That the choice was successful, it is necessary to observe some rules.
1. It is necessary to find the fullest information on object, efficiency, copper specifications. It is important, that you had answers to such questions, as:
- types of fuel which can be used for a copper;
- pressure under which in a fire chamber fuel arrives;
- antipressure of a fire chamber;
- Copper efficiency, its capacity or optimum capacity of a torch;
- method of regulation of capacity of a torch.
2. It is necessary to calculate exact capacity of a torch. At this stage there is nothing difficult: the scheme for calculation of capacity of a torch is extremely simple: the optimum capacity of a torch will equal to work of capacity of a copper on efficiency. That is the copper in capacity of 2500 kW and efficiency of 90 % needs a torch of 2780 kW.
3. It is necessary to calculate also TRG (a demanded consumption of gas) if it is a question of gas torches, certainly. TRG pays off so:
TRG = (capacity of a torch x 3,6) / warmth of combustion of gas. In other words, if the gas torch possesses capacity of 2780 kW, we will receive: (2780 kW x 3,6)/35,8 MDZh / cubic nanometer where 35,8 is an indicator of warmth of combustion of natural gas.
On the same formula it is possible to count amount of burned fuel, if a torch diesel. Thus it is necessary to use, respectively, value of warmth of combustion of fuel is 42,7 MDZh/kg. So, if to make calculations for a torch of 2780 kW, fuel consumption will make 234 groups of companies/hours.
4. It is necessary to study carefully the chart of dependence of antipressure and capacity. Thanks to these charts it is possible to define a working range of a certain torch. For example, the capacity of a torch makes 2780 kW at antipressure of a copper in 12 Mbar. At these parameters the working point will settle down in curve GP-280M. In case the point gets under a curve, for this antipressure of capacity of a torch will be enough.
The most optimum option – a point of a ratio of antipressure and capacity gets to area which most close settles down to the right edge. It is necessary to understand that at different ways of adjustment, at different types of applied fuel it is necessary to use own curve.
5. Now it is necessary to pick up the suitable valve for a gas torch. The same is demanded also by a torches combined. Choosing the valve, it is necessary to be guided by the special table depending on torch capacity. It is important to consider that tables were made for fire chambers which have antipressure of 0 Mbar. That is before using data from the table, it is necessary to reduce pressure of fuel to real value of antipressure of your fire chamber, and only after that it will be possible to use data from the table. Parameters of capacity are given in the table only for natural gas.
Let’s take for example, such situation: entering pressure of gas makes 70 Mbar, capacity of a gas torch – 2780 kW, antipressure – 12 Mbar. Using these parameters, we will receive that effective pressure of gas will make 58 Mbar (70-12) and for GP-280M torch in the optimum size of the valve there is DU 65.
6. It is necessary to check dimensions of a gas torch carefully. At this stage the special attention should be turned for length of a gorelochny head. It is a question not only of a gas torch. By the same principle diesel and black oil torches work. In an ideal the length of a gorelochny head should be such that it was either level with a fire chamber, or on 10-20 mm supported it.
7. Do not forget to check length of a torch. The special dimensional table here too can help. Remember that in operating time of a black oil, diesel and gas torch a flame to concern a wall of a fire chamber should not.
8. Being going to buy a torch, it is worth to remember as well about the additional equipment to which it is possible to carry such devices, as a regulator of pressure of gas, the thermostat, прессостат, pump fuel station.
Basic formulas which can be useful at a torch choice for a copper:
1. At calculation of capacity of a diesel, black oil, gas torch it is necessary to use a formula, in which torch capacity = copper/efficiency capacity (for efficiency of 90 % – 0,9).
2. At fuel consumption the capacity is necessary:
- for a steam copper of 1 t/h of steam – about 0,7 MWt of capacity;
- for a diesel copper of 1 kg/h – about 11,86 MWt of capacity at a diesel torch but only in case warmth of combustion of fuel will be equal 42,7 MDZh/kg;
- black oil copper of 1 kg/h – about 11,22 MWt of capacity for a black oil torch but only in case warmth of combustion of fuel will make 40,5 MDZh/kg;
- gas copper – 1 cubic nanometer/h – about 10 kW of capacity if warmth of combustion of natural gas makes 35,8 MDZh / cubic nanometer.
3. About a consumption of air. On each 10 kW of the capacity gas torches consume about 12-13 cubic m/h of air. As to black oil and diesel torches, they consume on each 10 kW of capacity about 13,5 cubic m/h of air.
4. For ensuring high-grade work of a black oil torch it is necessary to use station of heating, forcing, a fuel oil filtration.
In this case it is necessary to define, what capacity is necessary for the pump. For this purpose it is possible to use the following formula: minimum productivity, kg/h = (fuel consumption, kg/h + x, kg/h) * 1,25… 1,3, where x – size from 150 to 200 kg/h. The size in brackets represents volume of the fuel which is arriving in each torch and exposed to preliminary heating.