液压机工作原理及整体构造

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液压机工作原理及整体构造

Hydraulic machine classification, working principle, performance parameters

模压成型主要用于热固性塑料的成型。对于热塑性塑料，由于需要预先制取坯料，需要交替地加热再冷却，故生产周期长，生产效率低，能耗大，而且不能压制外形复杂和尺寸较为精确的制品，因此一般趋向于采用更经济的注射成型。

Compression molding is mainly used for the molding of thermosetting plastics. For thermoplastics, due to the need of prepared blank, needs to be alternately heated and cooled, so the production cycle is long, low production efficiency, high energy consumption, and can not be pressed product of complex shape and size accurately, so the general trend in the use of more economical injection type.

模压生产的主要设备是液压机，液压机在压制过程中的作用是通过模具对塑料施加压力、开启模具和顶出制品。

The main equipment for molding production is the hydraulic machine, hydraulic machine in the pressing process is through the mould for plastic pressure, die opening and ejection products.

模压用的压制成塑机（简称压机），为液压式压机，其压制能力以公称吨数表示，一般有40t ﹑63t﹑1OOt﹑160t﹑200t﹑250t﹑400t﹑500t等系列规格压机。多层压机有千吨以上。压机规格的主要内容包括操纵吨位、顶出吨位、固定压模用的模板尺寸和操纵活塞、顶出活塞的行程等。一般压机的上下模板装有加热和冷却装置。小型制件可以用冷压机（不加热，只通冷却水）专作定型冷却用，用加热压机专作热塑化用，这样可以节能。

Press for moulding into machine (referred to as the press ), as the hydraulic press, the suppression ability in nominal tonnage, generally 40t, 63T, 1OOt, 160t, 200t, 250t, 400t, 500t series of standard press. Multi-layer press has more than 1000 tons. The main contents include operating tonnage press specifications, ejector tonnage, fixed die with template size and operates the piston, the piston stroke. Template general compressor equipped with heating and cooling device. Small parts can be used cold press ( not only heating, cooling water ) for setting cooling, heating machine for plastification, this can save energy.

压机按自动化程度可分为手板压机、半自动压机、全自动压机；按平板的层数可分为双层和多层压机。

Press press the degree of automation can be divided into manual machine, semi-automatic machine, full automatic press; according to the flat layer can be divided into the bilayer and multilayer press.

(1)液压机工作原理液压机是以液压传递为动力的压力机械。压制时，首先把塑料加进敞开的模具内，随后向工作油缸通进压力油，活塞连同活动横梁以立柱为导向，向下（或向上）运动，进行闭模，终极把液压机产生的力传递给模具并作用在塑料上。模具内的塑料，在热的作用下熔融和软化，借助液压机所施压力布满模具并进行化学反应。为了排出塑料在缩合反应时所产生的水分及其他挥发物，保证制品的质量，需要进行卸压排气。随即升压并加以保持，此时塑料中的树脂继续进行化学反应，经一定时间后，便形成了不溶不熔的坚硬固体状态，完成固化成型，随即开模，从模具中取出制品。清理模具后，即可进行下一轮生产。

( 1 ) the hydraulic machine working principle of hydraulic machine is a mechanical power transmission by hydraulic pressure. When pressed, the plastic into the open mold, then to the

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working oil cylinder through the oil pressure, the piston together with the movable beam to column oriented, down ( or up ) movement, are closing, the ultimate hydraulic machine generated force is transferred to the mold and the role of plastics. The mould of plastic, under the action of heat melting and softening, with hydraulic machine applied pressure of full mold and chemical reaction. In order to remove plastic produced in the condensation reaction of water and other volatiles, ensures the quality of the products, the need for pressure relief vent. Then the boost and to maintain, the resin plastics on chemical reaction, after a certain period of time, will form the insoluble solid state does not melt the hard, complete curing molding mold, then, take out the products from the mold. After cleaning the mold, production can be carried out the next round.

从上述过程可知，温度、压力、时间是压制成型的重要条件。为了进步机器的生产率和运行的安全可靠，机器的运转速度也是一个不可忽视的重要因素。因此，作压制用的塑料液压机应能满足下列基本要求。

From the above process, temperature, pressure, time is an important condition for pressing. In order to productivity and operation progress machine is safe and reliable, the operation of the machine speed is an important factor that can not be ignored. Therefore, as should meet the following basic requirements plastic hydraulic machine press.

①压制压力应该足够并能调整，还要求在一定的时间内达到和保持预定压力。

The pressure should be adequate and can be adjusted, is also required to achieve and maintain a predetermined pressure in a certain period of time.

②液压机的活动横梁在行程中的任何一点位置上，都能停止和返回。这在安装模具、预压、分次装料或发生故障时，是十分必须的。

Moving beam of hydraulic press position at any point during the trip, can stop and return. In this installation mold, preloading, split charging or failure, is very necessary.

③液压机的活动横梁在行程中任何一点位置都能进行速度控制和施加工作压力。以适应不同高度模具的要求。

The movable beam of hydraulic press in travel in any position can be applied to speed control and working pressure. In order to adapt to different height requirements of die.

液压机的活动横梁，在阳模尚未接触塑料前的空行程中，应有较快的速度，以缩短压制周期，进步机器的生产率和避免塑料活动性能降低或硬化。当阳模接触塑料后即应放慢闭模速度，不然可能使模具或嵌件遭致损坏或粉料从阴模中冲散出来，同时放慢速度还可以使模内空气得到充分排除。

The movable beam of hydraulic press, air travel is not touch the plastic mold in before, the fast speed, so as to shorten the press cycle, progress machine productivity and avoid plastic activity reduced performance or hardening. When the male contact plastic after closing speed should slow down, or may make the mold or insert the destruction or powder dispersed out from the female die, at the same time to slow down the speed also can make the mold air fully exclude.

(2)结构和分类为典型下压式液压机的结构。它由机身（包括上横梁、下横梁、立柱等）、工作油缸、活动横梁、顶出机构、液压传动和电器控制系统等组成。工作油缸安装在上横梁上。活动横梁与工作油缸的活塞连接成整体，以立柱为导向上下运动（框式液压机以导轨为导向），并传递工作油缸内产生的气力，向塑料施压。考虑到装料和操纵的方便，液压机一般采用立式启闭模的形式。应用于塑料成型方面的液压机，可按以下数种方法进行分类。( 2 ) structure and the classification of typical under the pressure of hydraulic structure. It is composed of a body ( including the upper beam, beam, column and so on ), working cylinder, a movable beam, the ejection mechanism, hydraulic drive and electric control system etc.. The