The main products of Botou Junteng Casting Co., Ltd. are ductile iron manhole cover, ductile iron grate, ductile iron bench, die-cast aluminum parts, aluminum manhole cover, aluminum pump casing, cast aluminum elbow, aluminum lamp housing, aluminum alloy Three links and so on.
Because ductile iron manhole covers are very heat-treated, they can basically be divided into two categories. One is that the arrangement structure will not change or should not be changed through heat treatment, and the second is the basic arrangement structure. Onset changes. A heat treatment procedure is mainly used to eliminate internal stress, which is caused by the different cooling conditions and conditions in the stainless steel casting process. The arrangement, strength, and other mechanical properties do not change significantly due to heat treatment. Regarding the second type of heat treatment, the base arrangement has undergone obvious changes and can be roughly divided into five categories:
1. Softening annealing: The main purpose is to decompose carbides and reduce their hardness, and to improve the processing function. With regard to ductile iron, the intention is to obtain more ferrite arrangements.
2. Normalizing treatment: The primary intention is to obtain pearlite and sorbate arrangement to improve the mechanical function of stainless steel casting.
3. Quenching treatment: Firstly, in order to obtain higher hardness or abrasion strength, and at the same time to very high appearance wear resistance.
4. Surface hardening treatment: the first is to obtain a surface hardened layer, and at the same time obtain a very high surface wear resistance.
5. Separate hardening treatment: the first is to obtain high strength and the elongation is not changed drastically.
Ductile Iron Manhole Covers
The scale accuracy of the ductile iron manhole cover is related to many factors. Generally, the structure of the manhole cover, the material of the manhole cover, the mold making, the shell making, etc. will affect its accuracy. What should we pay attention to in order to reduce its shortcomings during processing? The aluminum electric motor shell supplier shares for you:
1. Influence of manhole cover structure: a. Manhole cover wall thickness is large, the shortening rate is large, and the manhole cover wall is thin, and the shortening rate is small. b. The free shortening rate is large, and the hindering shortening rate is small.
2. The effect of mold making on the shortening rate of manhole cover line: a. The influence of wax injection temperature, wax injection pressure, and holding pressure time on the mold scale is more obvious with the wax injection temperature, followed by the wax injection pressure, and the pressure holding time is to ensure the melting After molding, it has little effect on the final mold size. b. The linear shortening rate of wax (mold) material is about 0.9-1.1%.
3. The influence of manhole cover material: a. The casting shortening rate of common materials is as follows: casting shortening rate K = (LM-LJ) / LJ × 100%, LM is the cavity scale, and LJ is the manhole cover scale. b. The higher the carbon content in the material guess, the smaller the wire shortening rate, and the lower the carbon content, the greater the wire shortening rate.