Method for operating a crusher, a crushing system and a crushing plant
A method for operating a mineral material crusher, a system including a crusher, and a crushing plant. The mineral material crusher, includes a first crushing element and a second crushing element, defining a crusher gap therebetween. The crusher gap is maintained using at least one hydraulic cylinder, the hydraulic liquid pressure in at least one of the hydraulic cylinders is measured and hydraulic liquid is evacuated from the hydraulic cylinder when the hydraulic liquid pressure exceeds a set opening pressure limit. During the crushing process the following steps are repeated: generating, based on the hydraulic liquid pressure measurement, a representative value of a normal hydraulic liquid pressure in the at least one hydraulic cylinder caused by the crushable material in that crushing application; comparing the generated representative value and the set opening pressure limit; and selecting opening pressure limit which is higher than the measured normal hydraulic liquid pressure.
1. A method for operating a mineral material crusher during a crushing process, wherein the crusher comprises a first crushing element and a second crushing element, defining a crusher gap therebetween, the method comprising repeatedly performing during crushing process:
maintaining the crusher gap using at least one hydraulic cylinder during the crushing process;
measuring a hydraulic liquid pressure in at least one of the hydraulic cylinders during the crushing process;
generating a representative value of the hydraulic liquid pressure in the at least one hydraulic cylinder caused by crushable material during a certain crushing application based on one of an average and one or more peaks of the hydraulic liquid pressure measured in the at least one hydraulic cylinder;
setting a set opening pressure limit that is higher than the representative value of the hydraulic liquid pressure generated by a determined amount; and
evacuating hydraulic liquid from the at least one hydraulic cylinder to increase the crusher gap when the measured hydraulic liquid pressure in any of the at least one hydraulic cylinder exceeds the set opening pressure limit.
2. The method of claim 1 , further comprising setting the set opening pressure limit up to 100 bar higher than the representative value of the hydraulic liquid pressure.
3. The method of claim 1 , further comprising adjusting the set opening pressure limit of an adjustable pressure relief valve of the at least one hydraulic cylinder.
4. The method of claim 1 , wherein the at least one hydraulic cylinder comprises an adjustable pressure relief valve, the method further comprising:
opening the adjustable pressure relief valve of the at least one hydraulic cylinder to contract the at least one hydraulic cylinder when the hydraulic liquid pressure measured exceeds the set opening pressure limit; and
closing or maintaining closed the adjustable pressure relief valve when the hydraulic liquid pressure measured does not exceed the set opening pressure limit.
5. The method of claim 1 , further comprising presenting on a user interface at least one of the hydraulic liquid pressure measured in the at least one hydraulic cylinder and the set opening pressure limit.
6. A crushing system operable to repeatedly perform a crushing process, the crushing system comprising:
a mineral material crusher comprising a first crushing element and a second crushing element, wherein the first crushing element and the second crushing element define a crusher gap therebetween;
at least one hydraulic cylinder arranged and operable to maintain the crusher gap during the crushing process;
a pressure sensor configured to measure the hydraulic liquid pressure in the at least one hydraulic cylinder caused by the crushable material during the crushing process; and
a control unit configured to maintain the crusher gap during the crushing process by;
receiving a pressure measurement from the pressure sensor indicating the measured hydraulic liquid pressure in the at least one of the hydraulic cylinder during the crushing process;
generating a representative value of the hydraulic liquid pressure in the at least one hydraulic cylinder caused by crushable material during a certain crushing application based on one of an average and one or more peaks of the hydraulic liquid pressure measured in the at least one hydraulic cylinder;
setting a set opening pressure limit that is higher than the representative value of the hydraulic liquid pressure generated by a determined amount; and
evacuating hydraulic liquid from the at least one hydraulic cylinder to increase the crusher gap when the measured hydraulic liquid pressure in any of the at least one hydraulic cylinder exceeds the set opening pressure limit.
7. The crushing system of claim 6 , wherein the set opening pressure limit is up to 100 bar higher than the representative value of the hydraulic liquid pressure.
8. The crushing system of claim 6 , further comprising an adjustable pressure relief valve that is configured:
to open to contract the at least one hydraulic cylinder when the hydraulic liquid pressure measured exceeds the set opening pressure limit; and
to close or maintain closed the at least one hydraulic cylinder when the hydraulic liquid pressure measured does not exceed the set opening pressure limit.
9. The crushing system of claim 6 , further comprising a user interface configured to present at least one of the hydraulic liquid pressure measured and the set opening pressure limit.