叶轮是离心式压缩机或离心泵的核心部件,是腔体曲面复杂、厚度差异大的铝合金薄壁铸件.采用局部水冷工艺,通过设计专用水冷装置、控制开关时机、调整流量等措施,实现了铸件的顺序凝固,解决了采用传统工艺加工叶轮时易在局部位置产生缩松、热裂等缺陷的问题,提高了铸件成品率及质量.

为拓展杨木高附加值利用途径,对皱缩严重的杨木地板坯料进行汽蒸处理.结果表明:随着处理时间的延长,皱缩杨木地板坯料的含水率增加,皱缩深度减小.经汽蒸5h处理和干燥后,试样的皱缩深度明显减小.

Poplar( Populus tomentosa Carr.) lumber was thermally treated at 195°C for 3 hours and then subjected to hot pressing at 160° C. The compression sets and the pressure holding times were 18%,26%,34% and 10min,25min,40min,respectively. The influences of compression set and holding time on wood properties were studied. The results showed that surface hardness of the samples increased with the increasing of compression set and holding time,which was found 31%,64% and 88% higher corresponding to the compression set of 18%,26% and 34%,respectively. The modulus of elasticity and modulus of rupture also increased when higher compression sets were applied,but showed less correlation with holding time. The thickness swell increased when higher compression sets and less holding times were adopted.The average dimensional stability increased by 45%. The optimal compression ratio and holding time were 26% and25min,respectively. Poplar wood treated in this condition exhibited similar physical properties to ash wood. Furthermore,its dimensional stability could be 1. 9 times higher than ash wood.

The drying technology of Fraxinus mandshurica flooring blank using the method for connecting air-drying and kiln-drying were studied. The result showed that compared with the normal method, although the production time was prolonged to 2.5 days, the cost was decreased by 62. 43% -67.78%, and the drying rate was increased by 2. 0%.

The invention relates to a flame-retardant solid wood section, a flame-retardant solid wood floor and a production method of the flame-retardant solid wood section, which belong to the production and process technology of wood products. Wood is subject to heat treatment and flame retardant treatment so that the flame-retardant solid wood section and the flame-retardant solid wood floor are improved. The production method for the flame-retardant solid wood section sequentially includes steps of A, drying the wood; B, performing carbonization heat treatment, wherein the temperature can rise to 175 DEG C to 205 DEG C; C, realizing impregnation flame retardant treatment under normal pressure; and D, leading moisture content of the dried wood to range from 6.0% to 10.0%. By the aid of the method, advantages of wood subject to carbonization heat treatment and advantages of flame-retardant wood are integrated, shortcomings of the wood in carbonization heat treatment and shortcomings of the flame-retardant wood are overcome, the obtained solid wood section and the obtained solid wood floor are high in dimensional stability, corrosion resistance and weather resistance, flame retardant is filled at the depth ranging from 2mm to 6mm on surface layers, a flame retardant performance is good, and production cost is lower. The invention further provides the solid wood section and the solid wood floor which are manufactured by the production method for the flame-retardant solid wood section.