Non-standard cylinder type difference and cover good?

Cylinder, product related issues with the web site, and is a specific answer below, the main are: question 1: in the cylinder cover, the specific what effect is there? Question 2: ordinary cylinder with the cylinder, what is the difference between the two? These two questions, has been listed above. The below, before it's to answer, to save everyone's learning time, to improve the learning efficiency. Question 1: in the cylinder cover, the specific what effect is there? Cylinder head cover, the specific role is as follows: part one: the cylinder head cover and seal, avoid the pollution, and the oil leakage. Part two: to separate the oil with air, so as not to affect the work efficiency. 3: act as a oil filling mouth, also can be used as a sensor installation pedestal. Question 2: ordinary cylinder with the cylinder, what is the difference between the two? The difference between the cylinder and the cylinder, mainly in the speed, seal structure and the buffer on the structure of the three.