A load detection sensor capable of stably weighing a heavy object to be weighed in high precision. The amount of the pressure fluid supplied to the main cylinder body is increased before a workpiece is engaged with a table section arranged at an end of the main cylinder body so that pressing force, which is applied to the piston, is increased. Additional embodiments are disclosed. To make possible a recharge during the deceleration of a consumer, the precharge device can be pressurized in the direction of an elevation of the precharge pressure when there is a decreasing control signal of the control valve. The main processes of the sour gas production and treatment are described.