I. Work performance

(1) Accurate overprinting: This is one of the main indicators representing the work performance of the printing machine. In the printing process, whether at low or high speed, you can ensure that the paper delivery, handing and printing, etc. are in the specified position. This is even more important for the requirements of fine prints and color printing. This requires the drive system of the printing press, the transfer position and timing of the paper transfer, and the precision of the movement of the plate and impression press. Therefore, when we analyze printing, we must focus on understanding the various aspects related to register accuracy, grasp its characteristics and role.

(2) ink color uniformity and firmness: This is another indicator of printing quality. No matter which printing method is used, to print a clear and firm ink color, not only ink uniformity, but also requires sufficient printing pressure. Ink supply device and embossing mechanism should be able to meet this requirement.

(3) high productivity: the number of finished sheets per hour is generally used as a standard to measure the productivity of the printing press. With the rapid development of science, culture and education in China, the demand for various newspapers, magazines, books, etc. is increasing, and the demand for some printed materials is as high as millions or even tens of millions. Therefore, improving the productivity of the printing press is an important aspect of the development of the printing industry, the structural characteristics of the press often determines the level of its productivity. For example, the productivity of flatbed presses is very low, while round flatbed presses with impression cylinders have much higher productivity than flatbed presses, but the reciprocating motion of the plate table limits the productivity. Therefore, further improvements were made and gradually replaced by circular wheel presses. At present, printing presses are moving toward larger, high-speed, wheel conversion, linkage, and maximum productivity.

2. Performance

(1) Durable: The printing machine is required to maintain the original accuracy after long-term use, i.e., the machine has a long service life, which is economically important for national construction. To this end, the material and heat treatment process of the parts should be correctly selected to ensure the wear resistance of the parts and improve the operating accuracy of the transmission system. Each mating surface should have the correct geometric shape accuracy, good fit clearance and timely lubrication. and maintenance, etc.

(2) easy to operate: while improving the printing speed and automation, it must be convenient for workers to operate. Printing machine generally covers a large area and has multiple control panels to ensure that the operator can operate in all major work positions. Each control panel should be consistent with the human action habits, work position is easy to observe, the adjustment part of the intuitive and easy to touch.

(3) Reliability: To ensure that the operator's personnel and equipment, in addition to protection devices, printing presses are also equipped with safety devices, once the failure of the machine can automatically stop.

3. Process performance

Printing presses in the premise of meeting the work requirements, and strive for a simple and compact structure, good processing technology, reduce manufacturing costs, easy assembly and maintenance.

It should be noted that the above requirements often contradict each other. For example, it is not easy to achieve accurate overprinting at high speeds. Due to the further increase in speed, it will bring some new problems: the rapid and accurate transfer and delivery of paper, the rapid drying of ink, the stability of moving parts can be greatly affected, it is difficult to ensure the registration. The control device will increase the manufacturing cost of the machine. Another example is that there is a certain contradiction between the simple structure and the increased automation, printing speed and service life. Therefore, we can only use the above links as a starting point for analyzing the problem. According to the requirements of the printing process for the machine, grasp the main contradictions and weak links, weigh the big picture, and properly resolve the minor contradictions while meeting the main requirements. This is also the way of thinking that should be followed when learning about printing machines.