Hydrostatic test machine on couplings Equipments for the hydrostatic testing of GRP sleeve couplings with by width of 1.5 meters and diameters from 30 to 3000 mm that allows to test the single sleeves and also according to the BS 5480 standards appendix K and M and pressure of 2.5 to 30 bars. The test consists on checking the tightness with the rings and the tightness ring. The machine is composed by one set of plugs for the test, two heads supporting the plugs, oil-pressure system for the closing of the plugs, a hydraulic unit and one electrical board plus a set of sleeve plugs on pipes up to DN 3000.