What are the factors that affect the performance of large flanges?

　　Annealing temperature (annealing temperature is the temperature parameter when the primer and template are separated. When 50% of the primers and complementary sequences are double-stranded DNA molecules, the annealing temperature is an important factor affecting the specificity of PCR.

　　Ideally, the annealing temperature is low enough to ensure efficient annealing of homologous primers, and high enough to reduce non-specific separations. A reasonable annealing temperature range is 55 to 70 ° C. The annealing temperature is generally 5 ° C lower than the primer TM.

　　Can we reach normal temperature? Large flanges generally adopt solution heat treatment, commonly known as "annealing", and the temperature range is 1040 ~ 1120 ℃. You can also check the annealing furnace and find that the large flange fittings in the annealing zone should be incandescent, but not soften and sag.

　　Secondly, the tightness of the furnace body (furnace shell is welded by steel plate and section steel, and trolley is welded by steel section and steel plate). Through the soft contact sand sealing mechanism with the furnace lining, the trolley can reduce heat radiation and convection loss, and effectively ensure the tightness of the furnace body. The bright annealing furnace should be closed and isolated from the outside air. As long as an exhaust port is opened (for igniting the discharged hydrogen), the hydrogen is used as a maintenance gas. This inspection method can clean the gaps between the joints of the annealing furnace with soapy water to see if it can run away. The easiest outflow center is the center of the inlet and outlet tubes of the annealing furnace. This type of central seal is particularly prone to wear and should be inspected and replaced frequently.

　　Secondly, maintenance pressure, in order to avoid slight leakage, the furnace maintenance gas should adhere to a certain positive pressure, if it is hydrogen maintenance gas, generally requires more than 20kbar. Annealing atmosphere: Generally, pure hydrogen is used as the annealing atmosphere, and the purity of the atmosphere is greater than 99.99%. If the other part of the atmosphere is an inert gas, the purity can be reduced, but it must not contain excessive oxygen and water vapor.