vacuum gas quenching energy saving measures
One aspect of equipment:
1.1 mechanical pump
In fact, we know that when the mechanical pump is in use, as long as it enters the normal operation state, its operating load is quite low. The advanced vacuum furnace abroad, as well as several famous manufacturers of gas quenching furnaces in China, the new equipment under the condition of normal equipment. Basically, 7.5KW has been used in mechanical pumps (which do not exclude nameplate 7.5 actual 9-10KW).
Actual use effect, the initial vacuum time slightly increased, follow-up use completely unaffected, according to 300 days a day to open a furnace, each furnace process time 10 hours, gross estimate, 6x10x300 = 18000 kv, value is not worth changing, see the specific situation.
1.2 cooling water pump
Just like the last question, it belongs to the problem of new equipment.
Old equipment, generally centralized a pump water supply, and we know that the actual cooling water is divided into two parts, one part is responsible for the cooling of equipment components, such as water-cooled electrodes, sealing rings, vacuum pump sets, etc., the other part of the heat exchange system.
So the new idea is that, when the equipment works normally, the use of smaller pumps to ensure the protection of equipment components, in the hardening is about to start 10 minutes (or other safe time), open high-power pumps for heat exchanger, which not only reduces electricity consumption, but also can improve the cooling performance of the equipment.
This change involves too many conditions, preferably with equipment manufacturers.
Gas quenching process, in essence, is the workpiece to obtain enough cooling rate, so as to get M or B, and in our actual work, for the protection of deformation and cracking, generally less use of equipment limit cooling capacity, so in the case of ensuring the basic quenching capacity requirements, how to adjust the cooling performance of equipment has Articles can be done.
In a vacuum furnace, it is realized by several factors, such as gas pressure, gas flow rate, heat exchanger and cooling water. Specifically to the equipment, the corresponding pressure, fan speed, heat exchanger state, inlet and outlet water diameter, cooling water pump power, inlet water temperature (cooling water tank cooling capacity), the change of one factor will affect the final result. The cooling effect (which is partly due to the seasonal nature of the heat treatment quality), and an increase in one capability, when the cooling capacity of the equipment we require is fixed, means a relaxation of other capabilities, that is, a reduction in energy consumption.
For cooling pumps, see 1.2
An easy to ignore factor: inlet water temperature. How to achieve a lower inlet temperature can be achieved by expanding the volume of the cooling tank, or by accelerating the cooling capacity of the method, you can buy a few cooling towers cheaper, can also be made into a closed water circulation system (open cooling tower prevention and protection, another discussion), through additional equipment to cool down, with a tool Which is more suitable for the body?
1.4 convection heating in low temperature region
According to the heat radiation equation, the lower the temperature is, the slower the heating speed is. This can be verified from the actual production. It can save much time and energy by changing the heating mode of low temperature zone from radiation to convection. Heating capacity, so on the one hand is the value of convective heating can be achieved, such as low-temperature energy reduction, such as quenching isothermal, such as the occasional cascade under the tempering furnace, etc., on the other hand is the price increase, how to choose, depending on the actual situation of enterprises.
We have to remind a big premise, any process adjustment is based on the production of qualified products premise, otherwise it is hooliganism.
2.1 selection of sectional heating
Primary preheating efficiency is high, energy consumption is low, two preheating deformation risk is low, based on the judgment of other factors such as product status, determine whether the product is one preheating or two preheating.
2.2 quenching and holding time
The method of calculating the effective thickness according to the charging coefficient X is still introduced in the existing reference books. However, the calculating time is often quite different from the actual situation. How to ensure adequate heat preservation time, and not waste time and energy? More accurate calculation is needed.
2.3 rational charging
Simply put, big and big, small and small, but it needs enough workpiece to support, virtuous circle everyone thinks, the reality is different, to mention.
Write an essay, write it down, think of where to write, benevolent, wise, but also specific analysis of the situation.
Keep in mind Academician Pan's teachings: "There is no best process for heat treatment, only the most appropriate process." How to implement energy-saving, but also specific analysis of the specific circumstances of the correct response.