Here a way to learn Circulation Swage and Circulation Head

Circulation Swage / Head

The top of circulation head connects to the kelly, the bottom connects to the casing. It's used to circulate the cement slurry before cementing. Sometimes the cementing head can be replaced by lifting circulation head. 

Features:
1. Its upper end is drill pipe box or union, the nether end is casing pin. It's a crossover (X/O) with hollow inside.
2. Main body made of AISI4145H alloy steel.

Spec. 
2 7/8" IF* 4"  LTC ( BTC )            3 1/2" IF * 4 1/2" LTC ( BTC )

3 1/2" IF * 5" LTC ( BTC )            4 1/2" IF * 5 1/2" LTC ( BTC )

4 1/2" IF * 7" LTC (BTC )             4 1/2" IF * 7 5/8" LTC(BTC)

4 1/2" IF * 8 5/8"  LTC  (BTC)      4 1/2" IF * 9 5/8" LTC(BTC)
4 1/2" IF * 10 3/4" STC(BTC)      4 1/2" IF * 13 3/8" STC(BTC)
4 1/2" IF * 16" STC(BTC)            4 1/2" IF * 18 5/8" STC(BTC)
4 1/2" IF * 20" STC(BTC)