A method of cleaning coolants/lubricants

Abstract

 When, according to the method of the invention, an automatic cleaning system is constructed such that used cooling/lubricating agent (1) is first cleaned of metals (3) and then settles in a prechamber, tank (5), before being conveyed to an automatic filter (7), which is kept clean by backwashing, said agent being then cleaned of oil partly in an oil skimmer (11) and subsequently in an oil separator (12), the cleaned agent may be collected in a buffer tank (19), from which it may be sucked out for re-use in various working machines and the like.

Description

The prior art

[0001] The invention relates to a method of cleaning cooling/lubricating agents from a metal working machine and the like, said agent being conveyed to a separate cleaning system.

[0002] Coolants/lubricants are used particularly in CNC controlled working machines where the requirements of optimum cooling and lubrication are a prerequisite of the high speed working.

[0003] Cleaning systems of various types are known, but these are very complicated and thus expensive in manufacture as well as service/operation.

The object of the invention

[0004] The object of the invention is to provide a method which is both effective, simple and thereby relatively easy to keep in operation and service. This also allows the manufacture of relatively inexpensive systems, which may then be produced and set up in the form of cleaning units in immediate association with the working machines.

[0005] This is achieved according to the invention by a method wherein the agent is conveyed to the system through a metal remover, such as a magnet separator, following which the agent is conveyed to a tank, following which the agent is pumped through a self-cleaning filter for removal of particles from the agent, following which the agent is conveyed to an oil remover, such as an oil skimmer, following which the agent is conveyed through an oil separator and is finally conveyed to a tank from which the cleaned agent may be conveyed to the metal working machine for re-use as a coolant/lubricant.

[0006] With this simple method, the system may be given a compact configuration because of the structure and may be configured such that the two tanks essentially determine the size of the system and thereby its cleaning capacity.

[0007] When, as stated in claim 2, a self-cleaning filter is used, which cleans the filter elements with periodic backwashing, the system may operate automatically and without cumbersome handling operations.

[0008] When, as stated in claim 3, the backwashing agent is cleaned in a separate filter, this, too, may ensure a continuous cleaning effect.

[0009] Finally, it is expedient, as stated in claim 4, to keep the cleaned agent at a suitably low temperature of about 20 °C at which the cooling capacity is optimum.

The drawing

[0010] An example of a system for performing the method according to the invention will be described more fully below with reference to the drawing, which schematically shows the paths of the coolant/lubricant through the cleaning system.

Description of an exemplary embodiment of the system

[0011] The drawing shows an example of a system for performing the method according to the invention.

[0012] The system is built on the basis of two tanks, viz. a prechamber 5, to which the used coolant/lubricant 1 from the working machine is conveyed, and a cleaned agent tank 19, as will be described later.

[0013] Cleaning is initiated in that the used agent 1 passes through a magnet separator 2, which removes all metal parts from the agent, and which is provided with a depot 3 for metal in a generally known manner. The capacity of this magnet sepator may be up to 1500 I/min.

[0014] Then, the agent 4 is conveyed to the prechamber 5, the smaller tank, in which the agent settles so that separation of the oil emulsion emulsified in the agent will be as effective as possible in the subsequent step.

[0015] The agent 9 in the prechamber 5 is then sucked up by means of a pump 6 to be conveyed to a self-cleaning filter 7, a so-called automatic filter.

[0016] This filter is provided with filter rods of fabric having carefully specified cleaning effects, as it is automatically cleaned by the supply of the backwashing agent, which ensures that spare cleaning capacity is constantly available.

[0017] Cleaned backwashing agent 16, which may be of the order of 100-200 l/min, is then conveyed to a paper band filter 17, which filters the agent 18 and then conveys it to the second tank 19, the cleaned agent tank.

[0018] The agent 8 is pumped from the filter 7 to an oil remover in the form of an oil skimmer 11 which, from the liquid surface, automatically skims the oil from the surface and conveys this oil-containing agent 10 to an oil separator 12, a so-called coalescence separator, which separates the emulsified oil, which may then be conveyed to a collection tank (not shown) outside the tank 19.

[0019] The agent cleaned of oil is conveyed to the cleaned agent tank, the buffer tank 19, from which a pump 14 may suck the cleaned agent 13 for re-use as a cleaned coolant/lubricant 15, as indicated by the arrow pointing upwards.

[0020] The possibility of a fully automatically operating filter system is ensured in this simple manner where all the necessary functions are scanned and regulated using generally known control automatics.

[0021] To ensure the proper temperature of the agent of about 20 °C, it is possible to connect a cooling device for the agent 15 before it is conveyed to the working machines.

Claims

1. A method of cleaning cooling/lubricating agents from a metal working machine and the like, said agent being conveyed to a separate cleaning system, characterized in that the agent (1) is conveyed through a metal remover (2), such as a magnetic separator, following which the agent (4) is conveyed to a tank (5), following which the agent (9) is pumped through a self-cleaning filter (7) for removal of particles from the agent (9), following which the agent (8) is conveyed to an oil remover (11), such as an oil skimmer, following which the agent (10) is conveyed through an oil separator (12) and is finally conveyed to a tank (19) from which the cleaned agent (13) may be conveyed to the metal working machine for re-use as a coolant/lubricant.

2. A method according to claim 1, characterized in that the self-cleaning filter (7) is kept clean by backwashing, and that the backwashing agent (16) is conveyed to a filter (17), such as a band filter.

3. A method according to claim 2, characterized in that the agent (18) cleaned in the band filter (17) is conveyed to the tank (19) with the cleaned agent (13).

4. A method according to any one of claims 1-3, characterized in that the cleaned agent (13) is kept at a temperature of about 20 °C by means of a cooling system.

Drawing