隔爆接合面的紧固措施及要求

隔爆型电气设备常用的隔爆接合面型式有平面、止口、螺纹、粘接等几种。其中,平面及止口接合面主要通过螺栓、螺母紧固来限制间隙,其所用紧固件须采用工具才能松开或拆除的外六角或内六角螺栓等标准件。螺栓头下面的孔应选用中等精度配合尺寸,螺纹啮合应有裕量,I类设备外露紧固件其头部应采取护圈或沉孔保护措施;螺纹接合面应采用内六角紧定螺钉或等效的方法固定防止螺纹松动;透明件与隔爆外壳通常采用粘接方式,为确保安全及可靠性,还应采取压圈等其他紧固措施使组件的机械强度不能仅依赖粘接材料的粘接性。

Tightening Measures and Requirements of Flame-Proof Joint

The flame-proof electric apparatus has several commonly-used forms of flame- proof joints such as plane, spigot, thread and adhesive joints. Among them, plane and spigot joints are mainly used to limit gap by fastening bolt and nut. Its fasteners must be standard parts such as outer or inner hexagonal bolt which can be loosened or removed only by tools. The hole under the bolt head shall have fit size with medium precision, and thread engagement joint shall have allowance. The head of exposed fastener in class I apparatus shall take protection measures of retainer or counterbored hole. The thread joint shall adopt inner hexagonal set screw or equivalent measures to prevent thread from loosening. The transparent parts and flame-proof en- closure usually adopt adhesive method to ensure safety and realibility. The other tightening measures such as compression ring should also be taken to ensure that mechanical strength of component not only depend on adhesion of material.