RELIEF VALVE

To provide a relief vale capable of restraining back leakage of fluid from between a seat presser and a seat.SOLUTION: A relief valve comprises a seat 3 that is a valve body having an annular seal part 30 projecting from an annular bottom part 31, a disc 5, on which the seat is arranged, a seat presser 4 for fixing the seat, energization means 7 for energizing the disc, and a valve body 2, which is mounted to a valve space 92 of fluid equipment 9, and in which the disc to which the seat is fixed to inside by the seat presser, and the energization means are mounted. The seat presser penetrates through a center part 32 of the annular bottom part 31 of the seat, and has a small diameter part 41, on which a male screw part 41a screwed with a female screw part 51 is formed, and a large diameter part 40 coupled with the small diameter part. The large diameter part comprises an annular collar part 42 projecting in a radial direction. A contact face 42a contacting the annular bottom part of the annular collar part is inclined, so that thickness of the annular collar part becomes gradually thinner from an outside diameter to an inside diameter.SELECTED DRAWING: Figure 1 【課題】シート押えとシートとの間から流体が裏漏れすることを抑制することができるリリーフバルブを提供すること。【解決手段】円環状底部３１から突出する円環状のシール部３０を有する弁体となるシート３と、このシートを配備するディスク５と、シートを固定するシート押え４と、ディスクを付勢する付勢手段７と、流体機器９のバルブ空間９２に取り付けられる、内部にシートをシート押えで固定したディスク及び付勢手段を内装したバルブボディ２とを備え、シート押えは、シートの円環状底部３１の中心穴部３２を貫通し、雌ねじ部５１に螺合する雄ねじ部４１ａを形成した小径部４１及びこの小径部に連なる大径部４０を有し、大径部には径方向に突出する環状鍔部４２を備え、環状鍔部の円環状底部に当接する当接面４２ａは、組み立て密着前は、外径側より内径側に向かって漸次環状鍔部の厚みが薄くなるように傾斜している。【選択図】図１