为什么有些木门、木地板、木制家具等木制品销售出去以后会出现开裂、变形等质量问题呢?
显然,这些问题和木材的含水率紧密相连的。
01什么是含水率?
木材中的水分含量多少通常用含水率或含水量 (Moisture content,简称MC)来表示,即用木材中水分的质量与木材质量之比的百分数的方式表示。
含水率(质量含水率)moisture content
规定条件下测得的纺织材料中水分的重量占纤维湿重的百分数,不同于回潮率。
简单地说就是:
含水率=(湿重-土粒重)/湿重×100%
回潮率=(湿重-干重)/干重×100%
02掌握木材含水率的重要性
对于高素质的采购木制品的部门,随着专业知识的不断增长,也越来越多地注重木制品的含水率指标。过去国外的采购商就很注重这一指标,许多做出口产品和半成品的木业厂家对此深有体会。
一般而言,木制品制作完成后,造型、材质都不会再改变,此时决定木制品内在质量的关键因素主要就是木材含水率和干燥应力。
方料烘烤比板料烘烤难度大,因为料大,内部湿度难控制稍微掌握不好就会出现大面积干裂、变形以及曲翘的问题。
我国主要城市木材平衡含水率全年各月份含水率表:
城市 月份 | 一 | 二 | 三 | 四 | 五 | 六 | 七 | 八 | 九 | 十 | 十一 | 十二 | 年平均 |
北京 | 10.3 | 10.7 | 10.6 | 8.5 | 9.8 | 11.1 | 14.7 | 15.6 | 12.8 | 12.2 | 12.0 | 10.8 | 11.4 |
哈尔滨 | 17.2 | 15.1 | 12.4 | 10.8 | 10.1 | 13.2 | 15.0 | 14.5 | 14.6 | 14.0 | 12.3 | 15.2 | 13.6 |
齐齐哈尔 | 16.0 | 14.6 | 11.9 | 9.8 | 9.4 | 12.5 | 13.6 | 13.1 | 13.8 | 12.9 | 13.5 | 14.5 | 12.9 |
佳木斯 | 16.0 | 14.8 | 13.2 | 11.0 | 10.3 | 13.2 | 15.1 | 15.0 | 14.5 | 13.0 | 13.9 | 14.9 | 13.7 |
牡丹江 | 15.8 | 14.2 | 12.9 | 11.1 | 10.8 | 13.9 | 14.5 | 15.1 | 14.9 | 13.7 | 14.5 | 16.0 | 13.9 |
克山 | 18.0 | 16.4 | 13.5 | 10.5 | 9.9 | 13.3 | 15.5 | 15.1 | 14.9 | 13.7 | 14.6 | 16.1 | 14.3 |
长春 | 14.3 | 13.8 | 11.7 | 10.0 | 10.1 | 13.8 | 15.3 | 15.7 | 14.0 | 13.5 | 13.8 | 14.6 | 13.3 |
四平 | 15.2 | 13.7 | 11.9 | 10.0 | 10.4 | 13.5 | 15.0 | 15.3 | 14.0 | 13.5 | 14.2 | 14.8 | 13.2 |
沈阳 | 14.1 | 13.1 | 12.0 | 10.9 | 11.4 | 13.8 | 15.5 | 15.6 | 13.9 | 14.3 | 14.2 | 14.5 | 13.4 |
大连 | 12.6 | 12.8 | 12.3 | 10.6 | 12.2 | 14.3 | 18.3 | 16.9 | 14.6 | 12.5 | 12.5 | 12.3 | 13.0 |
呼和浩特 | 12.5 | 11.3 | 9.9 | 9.1 | 8.6 | 11.0 | 13.0 | 12.1 | 11.9 | 11.1 | 12.1 | 12.8 | 11.2 |
天津 | 11.6 | 12.1 | 11.6 | 9.7 | 10.5 | 11.9 | 14.4 | 15.2 | 13.2 | 12.7 | 13.8 | 12.1 | 12.1 |
太原 | 12.3 | 11.6 | 10.9 | 9.1 | 9.3 | 10.6 | 12.6 | 14.5 | 13.8 | 12.7 | 12.8 | 12.6 | 11.7 |
石家庄 | 11.9 | 12.1 | 11.7 | 9.9 | 9.9 | 10.6 | 13.7 | 14.9 | 13.0 | 12.8 | 12.6 | 12.1 | 11.8 |
济南 | 12.3 | 12.3 | 11.1 | 9.0 | 9.6 | 9.8 | 13.4 | 15.2 | 12.2 | 11.0 | 12.2 | 12.8 | 11.7 |
青岛 | 13.2 | 14.0 | 13.9 | 13.0 | 14.9 | 17.1 | 20.0 | 18.3 | 14.3 | 12.8 | 13.1 | 13.5 | 14.4 |
郑州 | 13.2 | 14.0 | 14.1 | 11.2 | 10.6 | 10.2 | 14.0 | 14.6 | 13.2 | 12.4 | 13.4 | 13.0 | 12.4 |
洛阳 | 12.9 | 13.5 | 13.0 | 11.9 | 10.6 | 10.2 | 13.7 | 15.9 | 11.1 | 12.4 | 13.2 | 12.8 | 12.7 |
乌鲁木齐 | 16.0 | 18.8 | 15.5 | 14.6 | 8.5 | 8.8 | 8.4 | 8.0 | 8.7 | 11.2 | 15.9 | 18.7 | 12.7 |
银川 | 13.6 | 11.9 | 10.6 | 9.2 | 8.8 | 9.6 | 11.1 | 13.5 | 12.5 | 12.5 | 13.8 | 14.1 | 11.8 |
西安 | 13.7 | 14.2 | 13.4 | 13.1 | 13.0 | 9.8 | 13.7 | 15.0 | 16.0 | 15.5 | 15.5 | 15.2 | 14.3 |
兰州 | 13.5 | 11.3 | 10.1 | 9.4 | 8.9 | 9.3 | 10.0 | 11.4 | 12.1 | 12.9 | 12.2 | 14.3 | 11.3 |
西宁 | 12.0 | 10.3 | 9.7 | 9.8 | 10.2 | 11.1 | 12.2 | 13.0 | 13.0 | 12.7 | 11.8 | 12.8 | 11.5 |
成都 | 15.9 | 16.1 | 14.4 | 15.0 | 14.2 | 15.2 | 16.8 | 16.8 | 17.5 | 18.3 | 17.6 | 17.4 | 16.0 |
重庆 | 17.4 | 15.4 | 14.9 | 14.7 | 14.8 | 14.7 | 15.4 | 14.8 | 15.7 | 18.1 | 18.0 | 18.2 | 15.9 |
雅安 | 15.2 | 15.8 | 15.3 | 14.7 | 13.8 | 14.1 | 15.6 | 16.9 | 17.0 | 18.3 | 17.6 | 17.0 | 15.3 |
康定 | 12.8 | 11.5 | 12.2 | 13.2 | 14.2 | 16.2 | 16.1 | 15.7 | 16.8 | 16.6 | 13.9 | 12.6 | 13.9 |
宜宾 | 17.0 | 16.4 | 15.5 | 14.9 | 14.2 | 11.2 | 16.2 | 15.9 | 17.3 | 18.7 | 17.9 | 17.7 | 16.3 |
昌都 | 9.4 | 8.8 | 9.1 | 9.5 | 9.9 | 12.2 | 12.7 | 13.3 | 13.4 | 11.9 | 9.8 | 9.8 | 10.3 |
拉萨 | 7.2 | 7.2 | 7.6 | 7.7 | 7.6 | 10.2 | 12.2 | 12.7 | 11.9 | 9.0 | 7.2 | 7.8 | 8.6 |
贵阳 | 17.7 | 16.1 | 15.3 | 14.6 | 15.1 | 15.0 | 14.7 | 15.3 | 14.9 | 16.0 | 15.9 | 16.1 | 15.4 |
昆明 | 12.7 | 11.0 | 10.7 | 9.8 | 12.4 | 15.2 | 16.2 | 16.3 | 15.7 | 16.6 | 15.3 | 14.9 | 13.5 |
上海 | 15.8 | 16.8 | 16.5 | 15.5 | 16.3 | 17.9 | 17.5 | 16.6 | 15.8 | 14.7 | 15.2 | 15.9 | 16.0 |
南京 | 14.9 | 15.7 | 14.7 | 13.9 | 14.3 | 15.0 | 17.1 | 15.4 | 15.0 | 14.8 | 14.5 | 14.5 | 14.9 |
徐州 | 15.7 | 14.7 | 13.3 | 11.8 | 12.4 | 11.6 | 16.2 | 16.7 | 14.0 | 13.0 | 13.4 | 14.4 | 13.9 |
合肥 | 15.7 | 15.9 | 15.0 | 13.6 | 14.1 | 14.2 | 16.6 | 16.0 | 14.8 | 14.2 | 14.6 | 15.1 | 14.8 |
芜湖 | 16.9 | 17.1 | 17.0 | 15.1 | 15.5 | 16.0 | 16.5 | 15.7 | 15.3 | 14.8 | 15.9 | 16.3 | 15.8 |
武汉 | 16.4 | 16.7 | 16.0 | 16.0 | 15.5 | 15.2 | 15.3 | 15.0 | 14.5 | 14.5 | 14.8 | 15.3 | 15.4 |
宜昌 | 15.5 | 14.7 | 15.7 | 16.3 | 15.8 | 15.0 | 11.7 | 11.1 | 11.2 | 14.8 | 14.4 | 15.6 | 15.4 |
杭州 | 16.3 | 18.0 | 16.9 | 16.0 | 16.0 | 16.4 | 15.4 | 15.7 | 16.3 | 16.3 | 16.7 | 17.0 | 16.5 |
温州 | 15.9 | 18.1 | 19.0 | 18.4 | 19.7 | 19.9 | 18.0 | 17.0 | 17.1 | 14.9 | 14.9 | 15.1 | 17.3 |
南昌 | 16.4 | 19.3 | 18.2 | 17.4 | 17.0 | 16.3 | 14.7 | 14.1 | 15.0 | 14.4 | 14.7 | 15.2 | 16.0 |
九江 | 16.0 | 17.1 | 16.4 | 15.7 | 15.8 | 16.3 | 15.3 | 15.0 | 15.2 | 14.7 | 15.0 | 15.3 | 15.8 |
长沙 | 18.0 | 19.5 | 19.2 | 18.1 | 16.6 | 15.5 | 14.2 | 14.3 | 14.7 | 15.3 | 15.5 | 16.1 | 16.5 |
衡阳 | 19.0 | 20.6 | 19.7 | 18.9 | 16.5 | 15.1 | 14.1 | 13.6 | 15.0 | 16.7 | 19.0 | 17.0 | 16.8 |
福州 | 15.1 | 16.8 | 17.6 | 16.5 | 18.0 | 17.1 | 15.5 | 14.8 | 15.1 | 13.5 | 13.4 | 14.2 | 15.6 |
永安 | 16.5 | 17.7 | 17.0 | 16.9 | 17.3 | 15.1 | 14.5 | 14.9 | 15.9 | 15.2 | 16.0 | 17.7 | 16.3 |
厦门 | 14.5 | 15.6 | 16.6 | 16.4 | 17.9 | 18.0 | 16.5 | 15.0 | 14.6 | 12.6 | 13.1 | 13.8 | 15.2 |
崇安 | 14.7 | 16.5 | 17.6 | 16.0 | 16.7 | 15.9 | 14.8 | 14.3 | 14.5 | 13.2 | 13.9 | 14.1 | 15.0 |
南平 | 15.8 | 17.1 | 16.6 | 16.3 | 17.0 | 16.7 | 14.8 | 14.9 | 15.6 | 14.9 | 15.8 | 16.4 | 16.1 |
南宁 | 14.7 | 16.1 | 17.4 | 16.6 | 15.9 | 16.2 | 16.1 | 16.5 | 14.8 | 13.6 | 13.5 | 13.6 | 15.4 |
桂林 | 13.7 | 15.4 | 16.8 | 15.9 | 16.9 | 15.1 | 14.8 | 14.8 | 12.7 | 12.3 | 12.6 | 12.8 | 14.4 |
广州 | 13.3 | 16.0 | 17.3 | 17.6 | 17.6 | 17.5 | 16.6 | 16.1 | 14.7 | 13.0 | 12.4 | 12.9 | 15.1 |
海口 | 19.2 | 19.1 | 17.9 | 17.6 | 17.1 | 16.1 | 15.7 | 17.5 | 18.0 | 16.9 | 16.1 | 17.2 | 17.3 |
台北 | 18.0 | 17.9 | 17.2 | 17.5 | 15.9 | 16.1 | 14.7 | 14.7 | 15.1 | 15.4 | 17.0 | 16.9 | 16.4
|
文章来源:网络
欢迎关注家居荟
长按二维码即可关注家居荟公众号,了解更多更有用和有趣的家居知识!