CONTROL VALVE WITH CONTACT SURFACE HARDENED END CAPS
An end cap assembly configured for use in a control valve and in combination with a spool includes a stater, the stater having a spool stop having a hardened surface.
1 . A control valve comprising:
a first end cap assembly arranged on a first side of the control valve and comprising a first stater having a first spool stop, the first stater having a first hardened surface at the first spool stop;
a second end cap assembly arranged on a second side of the control valve and comprising a second stater having a second spool stop, the second stater having a second hardened surface at the second spool stop;
a spool slidably disposed within the control valve;
the spool comprising a first contact surface facing the first spool stop and a second contact surface facing the second spool stop, the spool configured to slide between the first and second spool stops.
2 . The control valve of claim 1 wherein the first stater and the second stater are made of a magnetic steal selected from the group consisting of SAE 4140 steel, SAE 4142 steel, and SAE 4145 steel.
3 . The control valve of claim 2 wherein the first stater and the second stater are made of SAE 4140 steel having a hardness of about 200-250 HV0.5
4 . The control valve of claim 3 wherein the first hardened surface and the second hardened surface have a hardness of about 450-700 HV0.5.
5 . The control valve of claim 4 wherein the first hardened surface and the second hardened surface have a thickness of about 0.1-2.5 mm.
6 . The control valve of claim 3 wherein the first hardened surface and the second hardened surface have a hardness of about 662 HV0.5.
7 . The control valve of claim 6 wherein the first hardened surface and the second hardened surface have a thickness of about 0.1-1.0 mm.
8 . An end cap assembly configured for use in a control valve and in combination with a spool comprising:
a stater, the stater having a spool stop, the spool stop having a hardened surface.
9 . The end cap assembly of claim 8 wherein the stater is made of a magnetic steal selected from the group consisting of SAE 4140 steel, SAE 4142 steel, and SAE 4145 steel.
10 . The end cap assembly of claim 9 wherein the stater is made of SAE 4140 steel having a hardness of about 200-250 HV0.5
11 . The end cap assembly of claim 10 wherein the hardened surface has a hardness of about 450-700 HV0.5.
12 . The end cap assembly of claim 11 wherein the hardened surface has a thickness of about 0.1-2.5 mm.
13 . The end cap assembly of claim 10 wherein the hardened surface has a hardness of about 662 HV0.5.
14 . The end cap assembly of claim 13 wherein the hardened surface has a thickness of about 0.1-1.0 mm.
15 . The end cap assembly of claim 8 wherein the stater has a main body and the hardened surface has a hardness of about 180-350% harder than the main body.