Overview
A sealing flat washer is a thin, disc-shaped component placed under a bolt or nut to evenly distribute pressure and prevent leakage. It is critical in applications requiring fluid or gas containment, such as pipelines, engines, and hydraulic systems. Unlike standard washers, sealing variants often incorporate softer materials (e.g., rubber or PTFE) or coatings to enhance impermeability. They are standardized by metrics like inner/outer diameter and thickness, ensuring compatibility with industry fasteners.
Structure and Working Principle
The washer’s simple design comprises a central hole (inner diameter) matching the bolt size and an outer diameter that determines the sealing surface area. Under compression, the material conforms to microscopic irregularities in the mating surfaces. Metal washers rely on precise machining to avoid deformation, while elastomeric types compress to fill gaps. Composite designs (e.g., metal-rubber hybrids) combine structural integrity with sealing flexibility, ideal for high-vibration environments.
Key Features
Sealing flat washers are valued for their versatility. Metal variants (stainless steel, copper) resist high temperatures and corrosion, whereas rubber or PTFE washers excel in chemical resistance. Their uniform thickness ensures consistent load distribution, preventing joint loosening. Some feature coatings (e.g., nylon) to reduce friction during installation. Custom shapes (square, oval) address niche applications like electrical grounding.
Application Areas
Common uses include automotive engines (cylinder heads, oil pans), plumbing systems (pipe flanges), and industrial machinery (pumps, compressors). In aerospace, they secure fuel lines and hydraulic connections. Food-grade PTFE washers are essential in processing equipment to meet hygiene standards. Electrical applications utilize conductive metals to prevent static buildup.
Maintenance and Precautions
Inspect washers periodically for cracks, flattening, or chemical degradation. Replace them during routine maintenance to avoid system failures. Avoid mixing materials incompatible with operating fluids (e.g., rubber with petroleum). Use torque wrenches to prevent over-compression, which can rupture elastomeric washers or warp metal ones.
B2B Procurement Guide
Bulk purchases typically reduce costs by 10–30%. Specify material certifications (e.g., FDA compliance for food-grade washers) and request samples to test fitment. Leading manufacturers include Tecknit (USA), Zhejiang Zenith Rubber (China), and Frenzelit (Germany). MOQs vary; small suppliers may offer 1,000-unit orders, while large distributors require 10,000+ units.
Related Manufacturers
- 主营：硅橡胶垫片、丁腈橡胶垫片、石墨碳纤维轴套
- 主营：四氟垫、四氟圆板、四氟筛板、四氟密封环、PTFE铁氟龙密封、TFE四氟密封圈、密封垫片、四氟轴套、四氟刮板、光伏配件、蓝色四氟板、聚四氟乙烯、四氟加热器、反应炉配件、四氟模压板、改性四氟管、氢能源垫片、四氟法兰垫片、食品设备配件、四氟异型加工件、四氟非标加工件、四氟加工件、单晶硅反应炉光伏、铁氟龙板块、改性四氟垫片
- 主营：螺纹阀、涡轮蝶阀、立式止回阀、铸钢法兰底阀、升降式单向阀、自来水管开关、水泵吸水底阀、蒸汽锅炉阀门
- 主营：氧化铝空心球制品、刚玉莫来石承烧板、氧化铝陶瓷、陶瓷密封件、氧化锆陶瓷、氧化铝陶瓷板、氧化铝陶瓷管、氧化铝陶瓷棒、氧化铝陶瓷环、氧化铝陶瓷片、耐磨陶瓷、结构陶瓷、陶瓷定做、陶瓷加工、干压陶瓷、等静压陶瓷、刚玉陶瓷管、绝缘瓷柱、陶瓷管、陶瓷片、陶瓷环、陶瓷板、绝缘陶瓷、99氧化铝陶瓷板
- 主营：四氟垫片、金属缠绕垫片、三元乙丙橡胶垫、四氟包覆垫、丁晴橡胶垫、氟胶板、氟橡胶垫片、石棉垫片、碳素盘根、芳纶盘根、nas垫片、石墨盘根、非石棉垫片、石墨复合垫、膨体四氟垫、四氟盘根、软四氟垫、四氟弹性带、四氟板、nbr垫片、氟胶垫、橡胶板、生料带、ptfe板材
- 主营：钻尾丝、预埋板、预埋件、不锈钢平垫、自攻丝、连接件、扣丝杠、扣丝杆、自攻螺丝、镀锌丝杆、防水支架、镀锌牙条、镀锌丝杠、六角螺栓、法兰螺母、六角螺丝、化学锚栓、自攻螺钉、钢筋套筒、螺栓定制、弹簧垫片、穿墙丝杠、一体盖母、穿墙螺杆、光伏配件、膨胀螺栓
- 主营：导电橡胶、导电硅胶、导电硅橡胶、导电密封圈、导电密封屏蔽件、EMI电磁屏蔽密封条、导电橡胶密封件、硅橡胶密封圈、红色密封胶圈、导电屏蔽材料、导电橡胶条、导电硅胶条、导电O型圈、导电橡胶衬垫、导电橡胶板、导电硅胶板、EMI屏蔽橡胶条、电磁屏蔽条、镍碳导电橡胶条、硅胶O型圈、防水橡胶圈、石墨镀镍导电橡胶板、高导电硅胶O型圈、EMI橡胶板
- 主营：金属缠绕垫、金属包覆垫、四氟垫、锅炉密封材料、四氟包覆垫、陶瓷纤维布、石墨复合垫、钢包垫、橡胶板、石墨盘根、四氟板、石棉橡胶板、石墨填料环、芳纶盘根、四氟盘根、紫铜垫、金属带、石棉圆编绳、金属齿形垫
- 主营：三元乙丙橡胶条、EPDM、NEOPRENE、密封条、密封垫、密封胶条、EPDM密封条、EPDM密封胶条、密封垫片、密封胶带、丁腈橡胶密封条、EPDM密封垫、EPDM密封垫片、IXPE密封垫片、氯丁橡胶、硅胶、泡棉胶带、橡胶垫圈、隔振垫、发泡EVA、丁腈橡胶、硅橡胶、三元乙丙橡胶、聚氨酯海绵、PVC发泡
- 主营：地板贴、缓冲垫、发泡管、密封圈、止桨条、盲板阀、楼梯防、霓虹灯、电缆线、保护管、传送箱、配电箱、杆防砸、橡塑管、pvc防撞、束线管、裸导线、led硅胶、风琴板、卡边条、pvc墙角、保护条、护角条、发电板、杆防撞
- 主营：四氟板、戈尔盘根、油浸石棉、密封填料、密封材料、四氟弹性带、泥状软填料、陶瓷纤维带、石墨接地线、柔性接地电缆、高压石墨盘根、法兰滤网垫片、硅酸铝纤维绳、陶瓷纤维防火布、柔性石墨复合板
- 主营：高水基盘根
- 主营：陶瓷纤维、法兰垫片、高水基盘根、密封带、密封垫片、混编盘根环、高压石棉板、黑四氟盘根、氟橡胶垫片、玻璃鳞片胶泥、碳纤维盘根环、三元乙丙丁腈板、金属复合板垫片
- 主营：大口径胶管、高低压胶管、金属软管、密封件、尼龙压力树脂管、伸缩胶管、聚氨酯制品、硅胶管、橡胶软连接、复合软管、陶瓷胶管、橡胶制品、尼龙制品、四氟管
- 主营：缠绕垫、高温胶、石棉垫、密封带、密封绳、密封纸、石墨引、隔热布、隔热带、绝缘纸、橡胶圈、黑四氟、耐火绳、圆垫片、复合带、回转轴、石墨绳、油盘根、乙烯垫、真空泵、石墨垫、全棉带、石棉带、氟龙板、圆编绳