Safety devices plug BOP hydraulic coupling can be divided into thermal overload protection, overvoltage protection device two. 1, the thermal protection device: fusible plug is overheating protection device for coupling. 1) hydraulic coupling structure fusible plug plug body stepped through holes left in this hole perfusion fusible alloy. Fusible Sebu set in the fluid coupling at the maximum diameter of the lumen. Fusible allowed to install on the injection hole, but does not allow intentional or unintentional ordinary plug or fusible plug welded in place of the fusible plug to work. 2) thermal protection principles in the night when the brake coupling force or overload conditions, the loss of power is converted into heat, the working fluid rapid heating chamber. When the working fluid temperature to the permissible limit, the low-melting fusible alloy melt, then centrifuged working fluid discharged from the working pressure chamber via a fusible plug aperture, the liquid is sprayed in the working chamber is empty, hydraulic coupling the input and output medium is cut off due to job loss and no longer deliver power to effectively protect the motor, coupling work and running. 3) Select the principle function of temperature fusible plug (1) from security considerations, the role of low temperature fusible plug some of the more reliable, thus triggering frequent spraying fluid coupling empty. Therefore, under normal operating conditions and to ensure the safety, the role of fusible plug possible to select a higher temperature, but too high will accelerate the aging of the seal and the bearing capacity of the coupling housing decline. (2) the effect of temperature must be below the flash point of the working fluid. Under normal circumstances, the fusible plug melting point of 125 ℃, while also choose a special 140 ℃. (3) couplings are used in environments with explosive gas, should be carefully chosen fusible alloy melting point (lower appropriate choice); (4) the BOP fluid temperature control switches, to solve the coupling liquid jet caused by pollution and inconvenience Our self-designed thermostat switch; spray liquid temperature control switch works: YOXWK thermostat switch, add a slider in the original fusible plugs, overheating slider pop, push lever, lever again pushing the limit switch the power off or alarm. 2, overvoltage protection devices: Explosive plug is a fluid coupling overvoltage protection devices. 1) explosive plugs and flame retardant mainly used for liquid water medium hydraulic coupling, to prevent fluid coupling caused by the medium itself explosion pressures. 2) explosive plug works: Sese explosive core body pressing piece that is greater than 1.4Mpa own violent explosive alloy sheet (which must be purchased from the factory alloy sheet, be sure to be careful not to use other metal instead), When a predetermined pressure is reached, an explosive sheet rupture, the working fluid and gas is ejected from the coupling, and to prevent overvoltage burst. Fusible plug, plug blowout, explosion-proof plug, explosive plug, pump assembly parts, scoop, scoop fluid coupling, the disk, the disk coupling, shaft and bearing, hydraulic brake wheel couplings, coupling cycloid pump, coupling fusible plug M18 * 1.5, Plum pad, coupling plum pad, cushion couplings, fluid couplings fusible plugs, couplings fusible plug M24 * 1.5, coupling spoon pipes, hydraulic coupling plum plate, coupling seals, couplings seal, YOX, TVA-type hydraulic coupling constant filling, YOXR / P / N type of pulley-type hydraulic coupling, YOXⅡZ hydraulic coupling device, YOXE type easily removable hydraulic coupling, YOXIIZ constant filling fluid coupling, YOXP constant filling fluid coupling, YOX constant filling fluid coupling, YOXE constant filling fluid coupling, YOXZL limit filling fluid coupling, YOXII type constant filling fluid coupling, variable speed hydraulic coupling, coupling bearing