Need some advise.

[bluenote49]

The situation is I need to provide a 110 dia. pipe to the suction side of a pump, in which it will be tap/connected to a 200 dia. pipe. The problem is the 200 dia. pipe is the mainline and already installed to supply the network in building. So my question is what is the best way for me to connect this 110 pipe to the 200 mainline that would result in less fittings & save more money

Note: the only solution that I can think of is a flange tee(200 X 110) connection. The downside is the price. Btw the pipe is upvc.

 

[hydrae]

I assume your dimensions are mm?
As I am in the US, our sizes are in nominal inches. An in each size there are different OD depending upon the material and use. 4 inch pipe is similar in size to 100 mm.
4.00 steel, 4.13 cu tube, 4.22 pvc, 4.5 ips (steel, pvc, abs,+), 4.9 Cast iron or Ductile iron & 4.81 to 5.07 in AC you see the point,
Anyway a Hot tap aka live tap would be the solution, a tapping sleeve or Tee is installed on the existing 200mm pipe with a 100mm (nominal) valve.
A machine is installed on the open end of the valve and the valve is opened, the machine cuts a hole inside the sleeve, capturing the cut out portion (coupon), the bit is extracted outside the valve, the valve is closed, and machine is removed leaving a valve ready for connection.
This procedure is best done by an experienced crew, I am not familiar with UPVC but PVC can split lengthwise during this operation. Contact the local water supplier to see who does this work locally.

Hydrae