The Use Characteristic Of Large Diameter Flange And Fastener

In large flange production, there are many factors affecting the performance of large flanges, below we say a few common factors, the first is the annealing temperature (annealing temperature is primer and template combination of temperature parameters, when 50% of primers and complementary sequences are expressed as two-strand DNA molecule temperature · It is the most important factor affecting the specificity of PCR. In an ideal condition, the annealing temperature is low enough to ensure effective annealing of the primers with the target sequence, and high enough to reduce the non-specific binding. Reasonable annealing temperature from 55 ℃ to 70 ℃. The annealing temperature is generally set to 5 ℃ lower than the TM of the primer.

Whether the specified temperature annealing temperature reached the specified temperature. Large-scale flange treatment is generally to take the solution heat treatment, which is commonly called "annealing", temperature range of 1040~1120℃ (Japanese standard). You can also see through the annealing furnace observation hole, the annealed area of large flange fittings should be incandescent state, but did not appear softening droop.

The second is the furnace sealing (shell has steel and steel welded, trolley by steel and steel plate welding, trolley through the soft contact with the lining and sand sealing mechanism to reduce heat radiation and convection loss, effectively ensure the furnace sealing. ), the bright annealing furnace should be closed, isolated from the outside air, the use of hydrogen as a protective gas, only one vent is a pass (used to ignite the discharge of hydrogen). Check the method can be used soapy water to wipe the joints in the annealing furnace, to see if the tire; The easiest place to tire is the place where the stove is put into the pipe and out of the pipe, where the seal ring is particularly easy to wear and frequently checked.

The second is to protect gas pressure, in order to prevent leakage, the furnace protection gas should maintain a certain positive pressure, if it is hydrogen protection gas, the general requirements of more than 20kBar. Annealing atmosphere: Generally use pure hydrogen as annealing atmosphere, the atmosphere purity is better than 99.99%, if the other part of the atmosphere is inert gas, the purity can also be lower, but must not contain too much oxygen, water vapor.