影响铸钢件精度的原因有很多，主要有以下几点：
There are many reasons that affect the accuracy of steel castings, mainly including the following:
一、铸件结构的影响：
1、 The impact of casting structure:
（1）铸件壁厚，收缩率大，铸件壁薄，收缩率小。
(1) The casting has a thick wall and a high shrinkage rate, while the casting has a thin wall and a low shrinkage rate.
（2）自由收缩率大，阻碍收缩率小。
(2) The free shrinkage rate is high, while the hindered shrinkage rate is low.
二、制模对铸件线收缩率的影响：
2、 The influence of mold making on the linear shrinkage rate of castings:
（1）熔模存放时，将进一步产生收缩，其收缩值约为总收缩量的10%，但当存放12小时后，熔模尺寸基本稳定。
(1)
When the investment mold is stored, further shrinkage will occur, with a
shrinkage value of about 10% of the total shrinkage. However, after 12
hours of storage, the size of the investment mold is basically stable.
（2）射蜡温度、射蜡压力、保压时间对熔模尺寸的影响以射蜡温度至明显，其次为射蜡压力，保压时间在熔模成型后对熔模之后尺寸的影响很小。
(2)
The influence of wax injection temperature, wax injection pressure, and
holding time on the size of the investment mold is most significant at
the injection temperature, followed by the injection pressure. The
holding time has little effect on the size after the investment mold is
formed.
（3）蜡模径向收缩率仅为长度方向收缩率的30-40%，射蜡温度对自由收缩率的影响远远大于对受阻收缩率的影响（正确射蜡温度为57-59℃，温度越高收缩越大）。
(3)
The radial shrinkage rate of wax molds is only 30-40% of the length
direction shrinkage rate. The impact of wax injection temperature on the
free shrinkage rate is much greater than on the hindered shrinkage rate
(the correct wax injection temperature is 57-59 ℃, the higher the
temperature, the greater the shrinkage).
（4）蜡（模）料的线收缩率约为0.9-1.1%。
(4) The linear shrinkage rate of wax (mold) material is about 0.9-1.1%.
三、铸件材质的影响：
3、 The impact of casting material:
（1）材料中含碳量越高，线收缩率越小，含碳量越低，线收缩率越大。
(1)
The higher the carbon content in the material, the smaller the linear
shrinkage rate. The lower the carbon content, the greater the linear
shrinkage rate.
（2）常见材质的铸造收缩率如下：铸造收缩率K=（LM-LJ）/LJ×1，LM为型腔尺寸，LJ为铸件尺寸。K受以下因素的影响：蜡模K1、铸件结构K2、合金种类K3、浇注温度K4。
(2)
The casting shrinkage rate of common materials is as follows: Casting
shrinkage rate K=(LM-LJ)/LJ × 1. LM is the cavity size, and LJ is the
casting size. K is affected by the following factors: wax mold K1,
casting structure K2, alloy type K3, and pouring temperature K4.
四、型壳焙烧的影响：由于型壳的膨胀系数小，当型壳温度为1150℃时，仅为0.053%，因此也可以忽略不计。
4、
The effect of shell roasting: Due to the small expansion coefficient of
the shell, when the shell temperature is 1150 ℃, it is only 0.053%, so
it can also be ignored.
五、制壳材料的影响：采用锆英砂、锆英粉、上店砂、上店粉，因其膨胀系数小，仅为4.6×10-6/℃，因此可以忽略不计。
5、
The impact of shell making materials: Using zircon sand, zircon powder,
Shangdian sand, and Shangdian powder, due to their small coefficient of
expansion, it is only 4.6 × 10-6/℃, therefore it can be ignored.
