Roots fan has a variety of models, in the use of very much, when the need for Roots fan when we change how to select it, in some models, the parameters are very close. So the selection of Roots fan has the following points: List the conditions and requirements Use: the position and role of the blower in the process, distinguishing between blower use and vacuum use. Gas properties: name. Molecular weight, toxicity, corrosiveness and explosiveness, composition ratio of gas mixture, dust content, etc. Working condition parameters: inlet temperature, inlet pressure, boost (exhaust pressure or vacuum), flow rate, and permissible limits for exhaust temperature and noise, etc. Environmental conditions: installation place (...).

About the Dragon Boat Festival Holiday Notice Company partners: Dragon Boat Festival is coming, in order to respond to the call of the national statutory holidays, mobilize the enthusiasm of the staff, by the company decided to take a holiday of 3 days in Dragon Boat Festival, the holiday matters are notified as follows: I. Holiday time June 16, 2018 - June 18, 2018 holiday for three days, June 16th, 17th for the weekend normal rest, June 18th for the Dragon Boat Festival legal holiday, June 19th (Monday) as usual. Second, each department before the holiday to carry out routine checks to eliminate potential safety hazards. Including locking doors and windows, equipment cut off the power supply, important items properly stored, pay attention to fire and theft. Third, go out to visit relatives or home far away from the staff...