模切、烫印机现状及其发展

近年来,国内外的印前、印刷机械设备发展得非常迅速,而印后加工的模切、烫印机械设备就发展得相对较慢。田于印刷包装业的飞速发展,市场对模切、烫印技术和设备要求就越来越高。为了满足印包市场的需求,国内外许多厂家都竞相研制开发了一些各具特色的模切烫印机。制造模切、烫印机的国内外厂家很多,如:国外的公司有瑞士的博斯特公司、日本的旭恒铁工机械制造公司、三和公司。国内的公司有上海亚华印刷机械有限公司、唐山玉印集团、景德镇印刷包装机械有限公司、北人集团八达岭印刷机械厂、北京印刷联合公司、山西太行印刷机械有限公司、台州市人民印刷机械实业有限公司、广西金牛有限公司等。

北京精工模切 专业制造 务实创新

公司简介 北京精工模切机械制造有限公司是国内最早开发研究和生产圆压圆模切机的高新技术企业.公司现有员工100多人,大中专以上学历占95%以上,从事技术研究和管理的人员中有10位高级工程师,2位出国访问学者.

Method to determine installing angle of conical point attack pick

In order to obtain the determining method of the installing angle and decrease the performance indices (cutting force and wearing rate) of the pick, the relationships among the installing angles (impact angle, inclination angle and the skew angle) were studied, and the static model of installing angles of the pick was built. The relationships among the impact angle, the tip angle of pick and the kinematics parameters of the pick were built, too. Moreover, the mechanic models of the maximum clearance angle and the wearing angle of the pick were set up. To research the relationships of the installing angles and the change law of the wearing angle along with the kinematics parameters, the simulation was done. In order to verify the correctness of the models, the cutting experiments were done by employing two picks with different pick tip angles. The results indicate that, the cutting force is the smallest when the direction of the resultant force of pick follows its axis, and the relationship derived among the installing angles should be satisfied. In addition, to decrease the cutting force and the wearing of the pick, the tip angle of pick should not be larger than the half of the difference between the minimum wearing angle and the impact angle of the pick, and the clearance angle must not be less than zero.

Development of a Small-Scale Universal Apparatus for Evaluating Soil-Structure Interaction

This paper describes design and calibration procedures of a new small-scale testing apparatus for evaluating soil-structure interaction. Two distinct modes of loadings, such as, direct shear and pullout loadings on flexible and rigid reinforcements are implemented by the multiple functionalities of the apparatus through the use of single loading frame, dividing mechanism, instrumentation and data acquisition systems. The design is similar to the conventional apparatus; however, it includes some key modifications to adapt additional features of reinforcements. For the pullout test, the top half of the pullout box is fixed with the bottom half of the pullout box, while for the direct shear test, the top half is allowed to slide horizontally on low friction roller bearings connected to the driving mechanism. Mechanical loadings through a steel plate are used to apply the normal load in the pullout and direct shear apparatus. A series of shear and pullout tests are performed to validate the functionality of the apparatus and to examine relationships between the reinforcements and its shear and pullout resistances.

Deterioration of dynamic mechanical property of concrete with mineral admixtures under fatigue loading

The dynamic mechanical property of concrete is one of the key parameters,which greatly influences durability of infrastructures subjected to continuous heavy loading,such as girder and track slab of high-speed railway foundation structure.This paper reports serials of experiments designed to investigate the deterioration of dynamic mechanical properties of different concretes under fatigue loading condition.Four parameters including relative dynamic elastic modulus(RDEM),relative dynamic shear modulus(RDSM),relative compressive strength(RCS)and water absorption(WA)of concrete were evaluated to assess the dynamic properties and microstructures of concretes.Results show that the fatigue stress levels and fatigue cycle durations significantly influence the dynamic mechanical properties of concrete including dynamic elastic modulus and dynamic shear modulus.Addition of proper mineral admixture can improve the dynamic mechanical characteristics of concrete and increase its resistance against the fatigue loading effect.Keeping the amount of mineral admixture in concrete constant,its dynamic mechanical property with fly ash is lower than that with fly ash and silica fume.The water absorption in concrete,which is an indirect parameter reflecting capillary porosity,increases evidently after bearing fatigue-loading.There is a close correlation between the deterioration of dynamic mechanical property and the increasing of water absorption of concrete.This indicates that the damage of microstructure of concrete subjected to fatigue loading is the indispensable reason for the decay of its dynamic mechanical performance.