The disclosure relates to a heat exchanger (100) for heating a drilling fluid, comprising :

- an outer body (102) comprising an inner chamber (113) ;

- an inner element (104) fitted in the inner chamber;



said inner element comprising a helical groove (144), said groove and a wall (112) of the inner chamber defining a path for the fluid ;

and

- a heating source (106) for heat exchange with said path ;



the inner chamber further comprising at least one opening (116), the inner element being able to be removed from the inner chamber through said at least one opening ;

the outer body further comprising at least one removable lid (120) closing said at least one opening of the inner chamber.

Various implementations directed to analyzing a reservoir using fluid analysis are provided. In one implementation, a method may include determining mud gas logging (MGL) data based on drilling mud associated with a wellbore traversing a reservoir of interest. The method may also include determining first downhole fluid analysis (DFA) data based on a first reservoir fluid sample obtained at a first measurement station in the well bore. The method may further include determining predicted DFA data for the wellbore based on the first DFA data. The method may additionally include determining second DFA data based on a second reservoir fluid sample obtained at a second measurement station in the wellbore. The method may further include analyzing the reservoir based on a comparison of the MGL data and a comparison of the second DFA data to the predicted DFA data.

An analysis system for multimodal analysis of drilling mud (10) is disclosed. analyzing means, preferably and NMR or MRI device (26), are disposed about a drilling mud recirculation system and configured to communicate with the recirculation system's control system. The analyzing means are used to determine the value of a predetermined quality parameter Q. If fails to meet a predetermined quality criterion, the analysis system instructs the recirculation system to perform an action to alter the properties of the drilling mud such that the drilling mud returning to the drill rig will meet the quality criterion.

A system for improving a drilling speed by using drill string vibration comprises a downhole drill string vibration-reduction and supercharging device, and an ultra-high pressure bit device used for a downhole supercharger. The downhole drill string vibration-reduction and supercharging device comprises a high-pressure runner (16). The ultra-high pressure bit device used for the downhole supercharger comprises an ultra-high pressure drilling fluid transmission runner. The ultra-high pressure drilling fluid transmission runner comprises an ultra-high pressure drilling fluid runner (25), a high-pressure resisting hose (28) and a high-pressure resisting rigid tube (30). The high-pressure runner (16) is connected to the ultra-high pressure drilling fluid runner (25); an end of the high-pressure resisting hose (28) is connected to the ultra-high pressure drilling fluid runner (25), and the other end of the high-pressure resisting hose (28) is connected to the high-pressure resisting rigid tube (30); and the other end of the high-pressure resisting rigid tube (30) is connected to an ultra-high pressure drilling fluid nozzle (31). Also disclosed is a method for improving a drilling speed by using drill string vibration. The system structure is stable and reliable. Meanwhile, the power source in the method is the bit pressure fluctuation at the shaft bottom during drilling, and the injection pressure of the drilling fluid at the shaft bottom is improved by using energy obtained due to decrease of the bit pressure fluctuation. The adverse effect of the bit pressure fluctuation on the drilling procedure is reduced, which ensures construction safety and improves injection pressure of the drilling fluid at the shaft bottom, thereby improving the drilling speed.

Cette station de traitement des boues associée à un tunnelier (1) à front d'attaque pressurisé, comporte au moins un premier moyen (6) de régénération de la boue (B) provenant du front d'attaque du tunnelier, un deuxième moyen (7) de préparation de boue neuve dite boue mère (B1), un troisième moyen (8) de préparation d'un mélange de boue à utiliser dans le front d'attaque dite boue de marinage (B2), à partir des boues (B0, B1) issues des premier (6) et deuxième (7) moyens, un quatrième moyen (12) d'alimentation du front d'attaque en boue de marinage (B2), un cinquième moyen (13) de collecte et d'évacuation de la boue (B3) non utilisée, et non régénérable, un sixième moyen (14), intercalé entre les premier (6) et troisième (8) moyens et propre à diriger vers le cinquième moyen (13) une partie de la boue (B0, B1) issue du troisième moyen (8). Le sixième moyen (14) est adapté pour diriger, de manière réglable, vers le cinquième moyen (13) uniquement une partie de la boue (B0) régénérée issue du premier moyen (6).