tourist or business visa?

The difference between tourist vsia and business visa:
Tourist visa: Issued to an applicant who comes to China for tourist purposes, family visiting or other personal affairs.

Business Visa: Issued to an applicant who is invited to China for visit, research, lecture, business, scientific-technological and culture exchanges or short-term advanced studies or intern practice for a period of no more than six months.

The visa types are divided according to the purpose of coming to China, you travel to Chengdu for a business trip, however, you don't have the original copy of the visa notice (now called Invitation Letter of A Duly Authorized Unit or Confirmation of Invitation Letter), you can apply for tourist visa without providing this document, however, on the visa application form, you can choose business trip as the major puroise of your visits to China, you choose Tourism as the major purpose. Once you obtain a tourist visa, you can enter China without problem. Your entry is legal. You don't need to get a business vsia when you arrive in China. If the tourist visa only permits 14 days stay duration, you plan to stay in Chengdu for more than 14 days, you can apply for visa extension at the Chengdu Public Security Bureau before the expiration.