JPH1122688A - Water cooled oil free screw compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water cooled oil free screw compressor where the troubles of a water cooled heat exchanger can be reduced by managing the water quality thoroughly. SOLUTION: The cooling jackets in the first stage compressor body 2 and the second stage compressor body 4, an intercooler 6 and an outer cooler 7 for cooling the compressed gas and the lubricating oil, and a water treatment unit 21 are installed, whereby the water treatment is performed by applying the constant AC voltage to the cooling water at an inlet part of a cooling water passage 22 through which the water is sent to the coolers, and an alarm signal is output when the electric conductivity of the cooling water becomes more than a set value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-cooled oil-free screw compressor having a water-cooled heat exchanger.

[0002]

2. Description of the Related Art Conventionally, a water-cooled oil-free screw compressor equipped with a water-cooled heat exchanger, for example, a water-cooled intercooler, a water-cooled aftercooler, and a water-cooled oil cooler is well known. In the case of this type of compressor, the water supply to the water-cooled heat exchanger described above is the responsibility of the user, and the piping for supplying water to the water-cooled heat exchanger is installed by the user. The cooling water quality management is completely up to the user.

[0003]

In the above-mentioned conventional water-cooled oil-free screw compressor, water supply to the water-cooled heat exchanger is entirely up to the user, and equipment for controlling the quality of cooling water is provided in the compressor. I didn't even equip it. However, there are many troubles related to the quality of the cooling water, such as holes in the water-cooled heat exchanger and clogging of the heat exchanger due to the accumulation of scale. The current situation is that they are struggling to take measures against such troubles. The present invention has been made with the object of overcoming such a current situation, and a water-cooled oil-free screw compressor capable of thoroughly controlling water quality and reducing the occurrence of troubles in a water-cooled heat exchanger. It is something to offer.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a cooling jacket in a compressor main body, a cooling water flow passage through which a compressed gas and a lubricating oil are cooled. Water treatment was carried out by applying a constant AC voltage to the water, and a water treatment device for outputting an alarm signal when the electric conductivity of the cooling water exceeded a set value was formed.

[0005]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a water-cooled oil-free screw compressor according to the present invention.
A flow path for gas as a fluid to be compressed is formed following the stage compressor main body 2, the intermediate flow path 3, the second stage compressor main body 4, and the discharge flow path 5. The first-stage compressor main body 2 and the second-stage compressor main body 4 are of a well-known oil-free screw type having a water cooling jacket (not shown) inside. In addition, an intercooler 6 and an aftercooler 7, which are a type of water-cooled heat exchanger, are provided in the intermediate flow path 3 and the discharge flow path 5.

As shown by a dashed line in FIG. 1, an oil tank 11 passes through an oil pump 12, a water-cooled oil cooler 13, which is a type of water-cooled heat exchanger, and an oil filter 14, and then passes through the first stage compressor body 2, A lubricating oil flow path 15 is provided to reach a bearing, a shaft seal portion, and a gear portion (not shown) in the second-stage compressor main body 4 and further return to the oil tank 11 to circulate lubricating oil. Further, as shown by a thick solid line in FIG. 1, from the water treatment device 21, one is an intercooler 6, the water cooling jacket in the first stage compressor main body 2, the water cooling jacket in the second stage compressor main body 4, After further passing through the oil cooler 13, the other cooler 7
After passing through, a cooling water flow path 22 for discharging the cooling water out of the machine is provided as shown by an asterisk in FIG.

The water treatment apparatus 21 is located at the inlet of the cooling water flow path 22, performs water treatment by applying a constant rectangular wave AC voltage to the cooling water, and constantly detects the electrical conductivity of the cooling water. Then, when the electric conductivity exceeds a set value, an alarm signal is output. Then, by providing the water treatment device, silica in the cooling water flowing into the cooling water flow path 22,
By dissolving suspended matters such as calcium, the adhesion of these suspended matters to the metal in each cooler is suppressed, and when the layer of adhesion to the metal has a certain thickness, it is easy to be washed away by a water stream, and each cooler is cooled. Intervals for washing water have been extended, and water quality management has been thoroughly enforced.
Further, when the amount of suspended matter in the cooling water increases, the electric conductivity of the cooling water increases. Therefore, by detecting this, an alarm signal is issued and an instruction for flushing of the cooling water can be issued.

[0008] It is desirable that the water treatment apparatus 21 be operated when cooling water is flowing, regardless of whether the compressor is operating. In the above embodiment, the two-stage compressor is described. However, the present invention is not limited to this, and the water treatment device 21 is provided at the inlet of the cooling water flow path of the single-stage or multi-stage compressor. This includes the installed compressor.

[0009]

As is apparent from the above description, according to the present invention, the cooling water is provided at the inlet of the cooling water flow passage through which the cooling jacket, the compressed gas and the lubricating oil cooler in the compressor main body pass. The cooling water is subjected to water treatment by applying a constant AC voltage to the cooling water, and an alarm signal is output when the electric conductivity of the cooling water exceeds a set value. For this reason, there is an effect that it is possible to reduce the occurrence of troubles in the water-cooled heat exchanger.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of a water-cooled oil-free screw compressor according to the present invention.

[Explanation of symbols]

2 1st stage compressor main body 4 2nd stage compressor main body 6 intercooler 7 aftercooler 13 oil cooler 21 water treatment device 22 cooling water flow path

Claims (1)

[Claims] A water treatment is performed by applying a constant AC voltage to the cooling water at an inlet of a cooling water flow passage through which a cooling jacket in the compressor main body, a compressed gas and a lubricating oil cooling cooler flows. A water-cooled oil-free screw compressor characterized by being provided with a water treatment device that outputs an alarm signal when the electric conductivity of the cooling water exceeds a set value.