筛绢(简称为筛网)，是面粉厂的重要辅助材料。 1、筛网的分类及选用标准 面粉厂所用的筛网依材质而分大致有以下几种： 蚕丝筛网：由多股天然蚕丝绞织成丝，然后再经编织而成，特点是弹性好、不易松弛、孔眼尺寸不易变形、具有良好的吸湿性及放湿性、较不易产生静电等。但是不耐磨、易起毛。 锦纶(尼龙)筛网：由聚酰氨单丝纤维编织而成。耐磨、使用寿命长，高强度，综合使用效果好。 涤纶筛网，由聚酯纤维单丝编织而成。强度高，不易变形，但较之尼龙网，耐磨性及抗静电效果略差。 面粉厂也曾普遍使用丝质筛网直到二十世纪四十年代，当时用于分级的筛网一般有特料筛绢(14-72号)、三料筛绢(7-72号)两种，大致相当于开口尺寸1600－200um；用于筛粉的筛网，则有标准(代号S，3－25S)、单料筛绢(代号X，4X-17X)、双料筛绢(代号XX，3-17XX)、三料筛绢(代号XXX，3XXX-18XXX)几种，大致相当于筛孔尺寸300－60um。 面粉厂也普遍使用蚕丝网，标注也是引自国外行业规范而来的，“GG”(GitGauze)指粗料筛网，意为每一维也纳英寸(约等于1.0375英寸)长度内筛孔数，编织方式为全绞织，“XX”指细料筛网，主要用于粉筛，半绞织方式。 筛网的标注以公制为基础，如CB、JQ、JCQ等都表示每厘米中的筛孔数，材料有了蚕丝、锦纶和锦蚕交织，编织方式有了平纹织、半绞织、全绞织和方平织。 随着引进制粉生产线配套的进口尼龙筛网材料以其寿命长、性能好开始引起业内人士的关注，且直接以筛孔的尺寸大小为标注，此开口尺寸已系列化、标准化、规范化，并考虑了行业称谓及连惯性，分别以“GG,XXX,”对应，其中“GG”是平纹织；“XXX”是平纹织增强型，也是面粉厂应用最多的，编织方式为单、双经向重平织，通用称谓：“XX”。 进口筛网称谓中的“GG、XX、XXX”含义与大家熟悉的筛网而言，已起了较大变化，“XXX”丝径粗，使用寿命长，“XX”尺寸稳定，且有效筛理面积略大，表面粗糙化程度高自动分级效果好。 代号“JM”(单双经向重平织)、“JMG”(平纹织)，现还推出一种“PDM”(单双经向重平织)，规格与进口筛网有差异，但相接近。 耐磨程度：很大程度上决定了筛网的使用寿命，对同种材料的筛网而言，丝径越粗，耐磨性越好。 抗静电性：凡是面粉筛网都要求做抗静电处理，这是因为纤维与纤维、纤维与物料间的接触和摩擦，会造成电荷在纤维表面间的转移，产生静电现象，又由于面粉粒度较细，易被电荷吸引造成过筛困难，甚至糊网。 涤纶、尼龙都要进行抗静电处理，一般有以下几种方法： 1.表面处理：一般用抗静电剂处理； 2.聚合处理：在合成纤维聚合时，加入亲水性的聚合物或导电性低分子聚合物； 3．导电纤维：如在单丝中心加入碳素或在整根单丝加入碳素； 4．采用高能辐射，如γ辐射线或电子束辐射织物，使纤维变性，提高吸湿性，增加抗静电效果。 后三种方法实际上是材料防静电处理，属永久性， 第一种方法属于表面防静电。 幅宽：随着制粉工艺和粮机技术的发展，尤其是八辊磨及大产量高方平筛的出现，确实对制粉效率的提高、产能的增加创造了条件。所以筛格也相应伴随着此发展方向沿标准型、扩大型、超大型方向发展，进口筛网幅宽也有1.10米、1.36米、1.54米(筛网幅宽1.04－1.27米)，一定要根据各厂使用的筛格标准选购合适的幅宽。Silk sceen (the sceen), is an impotantauxiliay mateial flou factoy.Theclassification and selection standads, 1 sceenThe sceenwith the flou mill and divided by mateial geneally have the following:Silk sceen:by stands of natual silk skein silk, and then woven, is chaacteized by goodelasticity, not easy to loose, hole size, not easy to defomation, with goodmoistue absoption and desoption, is not easy to geneate static electicityetc.. But do not wea, easy pilling.Polyamide(nylon) sceen by polyamide monofilament fibe woven. Wea esistant, longsevice life, high stength, compehensive use of good esults.Polyestemesh, woven fom polyeste monofilament. High stength, not easy todefomation, but compaed with nylon mesh, wea esistance and antistaticeffect is slightly wose.Foeignflou factoy also has been geneally used in the foties of the silk sceenuntil the twentieth centuy and used, fo the time being, gading sceengeneally have especially sieve numbe 14-72 (silk), thee mateial sieve silk(No. 7 72), oughly equivalent to the size of the opening of the 1600 - 200um;sceen fo sifte, standad (code s, 3 - 25s), unblended sieve double and silk(code named x, 4X-17X) silk sceen (code named XX, 3-17XX), thee mateialsieve silk (code named XXX, 3XXX-18XXX) seveal, oughly equivalent to the meshsize of 300 - 60um.Domesticflou mill is also commonly used silk net, tagging is a quote fom aboadindusty noms and, "GG" (git Gauze) efes to the coase sceen,meaning each Vienna inches (appoximately equals 1.0375 inches) within thelength of the sieve numbe, weave pattens woven fo the cutte, "XX"efes to the fine mateial sieve net, mainly used fo sifting and half twistweave mode.The sceenannotation based on metic, such as CB, JQ, JCQ etc. have expessed pecentimete of sieve numbe, mateials with silk, nylon and bocade silkwomintetwined, woven with plain weave, half twist weave, the twist weave andbasket weaving.With the intoductionof powde poduction line suppoting the impot nylon mesh mateial in its longlife, good pefomance began to cause the attention of the pesonage insidecouse of study, and diectly to the size of the mesh mak and the opening sizehas been seialized, standadized, standadization, and conside theappellation of the industy and even inetia, espectively to "GG,XXX," coespondence, which "GG" is weave; "XXX" isplain woven enhanced and lagest flou mill application of, weave pattens fosingle and double wap to heavy flat fabic, the geneic name: "XX".Impotsceen name "GG, XX, XXX," meaning and the familia domestic sceen,has played a geat changes, "XXX" wie diamete thick, long sevicelife, "XX" dimensional stability and effective sceen aea slightlylage, suface ough degee of high automatic gading effect is good.Domesticcode "JM" (single and double by to flat fabic), "JMG"(weave), we also launched a PDM "(single and double wap to flat fabic),specifications and impot sceen have diffeences, but close.Thewea-esisting degee: to a lage extent detemines the sevice life of thesceen, the sceen of the same mateial, the thicke the wie diamete is andthe bette wea esistance.Antistaticpopety: any flou sieve equie antistatic teatment. This is because of thecontact and the fiction between the fibe and the fibe, the fibe and themateial, caused by the chage tansfe between the fibe suface,electostatic phenomena, and the flou paticle size is fine, easy to be chageattact caused difficult sieving, even paste.Polyeste,nylon ae to cay out anti-static teatment, geneally have the followingmethods:1 sufaceteatment: the geneal use of anti - static agent;2polymeization pocess: in the synthesis of fibe polymeization, the additionof hydophilic polyme o conductive low molecula polyme;3: as in thecente of the conductive fibe monofilament cabon o in the whole filamentwith adding cabon;4 the use ofhigh-enegy adiation, such as gamma adiation o electon beam adiationfabic, so that the fibe degeneation, impove moistue absoption, inceasethe anti-static effect.The lastthee methods ae in fact the mateial of anti - static teatment, which ispemanent, the fist method is the suface anti-static.Width: with the development of flou milling and gain technology,especially the emegence of eight olle mill and high yield and high Fangpingsceen, indeed impove the pulveizing efficiency, capacity incease to ceatethe conditions. So gizzly also along with the coesponding the developmentdiection along the standad type, expansion of lage and supe lage diectiondevelopment, impot sceen width also 1.10 metes, 1.36 metes, 1.54 metes(domestic sceen width 1.04 - 1.27 m), must be based on diffeent plants meshciteia to select appopiate width.