connected by sample line 9 sensor 3 detects at once any possible oil leakages at the drilling oil side as well as at the glycol water side flowmeters 7 and 8 are connected by a closed circulation circuit 11 these serve to control the cooling capacity and to detect any possible pollution of the plate packages at the drilling oil side of the first plate heat exchanger a manifold is provided in order to in the case of contamination turn the flow in order to flush back in this manner the contamination by using two heat exchangers 1 and 2 it is prevented in the case of leakage of the drilling oil cooler that oil ends up directly in the sea heat exchanger mud glycol cooler the plate type heat exchanger 2 is equipped with titanium plates and provided with epdm clip on sealing the capacity of the heat exchanger is 2000 kw based on a flow of 750 lem mud with an inlet temperature of 85 u00b0 c and 2000 l min ethylene glycol with an inlet temperature of 45 u00b0 c the fluid direction is countercurrent and the design pressure is 10 bar the plate type heat exchanger 1 is equipped with titanium plates with epdm clip on sealing the capacity of the heat exchanger is 2000 kw based on a flow of 2000 lem ethylene glycol with an inlet temperature of 59 u00b0 c and an outlet temperature of 45 u00b0 c seawater flow is based.