阀门经过长期使用后，阀瓣和阀座的密封面会发生磨损，严密性降低。修复密封面是一项量大且十分重要的工作，修复的主要方法是研磨，对磨损严重的密封面，是先堆焊经车削加工后再研磨。阀门的研磨包括：清洗和检查过程；研磨过程；检验过程。

　　After long-term use, the sealing surfaces of the valve disc and seat will wear and the tightness will decrease. Repairing the sealing surface is a large and very important task, and the main method of repair is grinding. For severely worn sealing surfaces, it is first welded and turned before grinding. The grinding of valves includes: cleaning and inspection processes; Grinding process; Inspection process.

　　1、清洗和检查过程清洗密封面在油盘内，使用专业清洗剂，边洗边检查密封面的损坏情况。用肉眼难以确定的细微裂纹可用着色探伤法进行。

　　1. Cleaning and inspection process: Clean the sealing surface in the oil pan, use professional cleaning agents, and inspect the damage of the sealing surface while washing. Minor cracks that are difficult to determine with the naked eye can be detected by dye penetrant testing.

　　经过清洗后，应检查阀瓣或闸阀与阀座密封面的密合情况，检查时用红色和铅笔。用红丹试红，检查密封面印影，确定密封面密合情况；或用铅笔在阀瓣和阀座密封面上划几道同心圆，然后将阀瓣与阀座密合旋转，检查铅笔圆圈擦掉情况，确定密封面的密合。如果密合不好，可用标准平板分别检验阀瓣或闸板密封面和阀体密封面，确定研磨部位。

　　After cleaning, the sealing surface between the valve disc or gate valve and the valve seat should be checked for tightness using red and pencil. Use red lead to test for redness, check the seal imprint on the sealing surface, and determine the sealing condition of the sealing surface; Or use a pencil to draw several concentric circles on the sealing surface of the valve disc and valve seat, then rotate the valve disc and valve seat tightly, check the wiping off of the pencil circle, and determine the sealing surface tightness. If the sealing is not good, a standard flat plate can be used to inspect the sealing surface of the valve disc or gate and the sealing surface of the valve body separately to determine the grinding area.

　　2、研磨过程研磨过程实质上是不用车床的切削过程，阀头或阀座上的麻点或小孔深度一般都在0.5mm以内，可以采用研磨的方法进行检修。研磨过程分为粗磨、中磨和细磨。

　　2. The grinding process is essentially a cutting process without the use of a lathe. The depth of the pits or small holes on the valve head or seat is generally within 0.5mm, and can be repaired by grinding. The grinding process is divided into coarse grinding, medium grinding, and fine grinding.

　　粗磨是为了消除密封面上的擦伤、压痕、蚀点等缺陷，使密封面得到较高平整度和一定的光洁度，为密封面的中磨打下基础。粗磨利用研磨头或研磨座工具，采用粗粒砂纸或粗粒研磨膏，其粒度80#-280#，粒度粗，切削量大，效率高，但切削纹路较深，密封面表面较粗糙。因此，粗磨只要平整地把阀头或阀座的麻点去掉即可。中磨是为了消除密封面上的粗纹路，进一步提高密封面的平整度和光洁度。采用细粒砂纸或细粒研磨膏，其粒度为280#-W5，粒度细，切削量小，有利于降低粗糙度；同时应更换相应的研具，研具应清洁干净。中磨完后，阀门的接触平面应达到光亮。如用铅笔在阀头或阀座上划几道，将阀头或阀座对着轻转一圈，应把铅笔线抹去。细磨是阀门研磨的后一道工序，主要是提高密封面的光洁度。细磨时可用W5或更细的微份与机油、煤油等稀释后，用阀门的阀头对着阀门的阀座进行研磨，而不用演剧，这样更有利于密封面的密合。研磨时一般顺时针方向转60-100°左右，再反方向转40-90°左右，轻轻地磨一会儿，必须检查一次，待磨得发亮发光，并在阀头和阀座上可以看到一圈很细的线，颜色达到黑亮黑亮的时候，再用机油轻轻地磨几次，用干净的纱布擦干净即可。研磨完以后，再把其他缺陷消除，即应尽快地组装，以免破坏一磨好的阀头。手工研磨不管粗研还是细研，均是始终贯穿提起、放下；旋转、往复；轻敲、换向等操作相结合的研磨过程。其目的是为了避免磨粒轨迹重复，使研具和密封面得到均匀的磨削，提高密封面的平整度和光洁度。

　　Rough grinding is used to eliminate defects such as scratches, indentations, and corrosion points on the sealing surface, resulting in higher flatness and a certain degree of smoothness, laying the foundation for intermediate grinding of the sealing surface. Coarse grinding uses a grinding head or grinding seat tool, using coarse-grained sandpaper or coarse-grained grinding paste, with a particle size of 80 # -280 #, coarse particle size, large cutting amount, high efficiency, but deep cutting patterns and rough sealing surface. Therefore, rough grinding only needs to remove the rough spots on the valve head or seat smoothly. Medium grinding is used to eliminate rough patterns on the sealing surface, further improving the flatness and smoothness of the sealing surface. Using fine-grained sandpaper or fine-grained grinding paste, with a particle size of 280 # - W5, fine particle size, small cutting amount, which is conducive to reducing roughness; At the same time, the corresponding research tool should be replaced and cleaned thoroughly. After grinding, the contact surface of the valve should reach a bright state. If you use a pencil to make a few lines on the valve head or valve seat, turn the valve head or valve seat lightly and wipe off the pencil line. Fine grinding is the next process after valve grinding, mainly to improve the smoothness of the sealing surface. When grinding finely, W5 or finer particles can be diluted with engine oil, kerosene, etc., and then the valve head of the valve can be used to grind against the valve seat of the valve, without the need for drama, which is more conducive to the sealing surface. When grinding, it is generally turned clockwise by about 60-100 ° and then counterclockwise by about 40-90 °. Gently grind for a while, and it must be checked once. When the grinding is bright and shiny, a circle of very thin lines can be seen on the valve head and seat. When the color reaches black and shiny, gently grind it several times with engine oil and wipe it clean with clean gauze. After grinding, other defects should be eliminated and assembled as soon as possible to avoid damaging the polished valve head. Manual grinding, whether coarse or fine, always involves lifting and lowering throughout the process; Rotation and reciprocating; The grinding process that combines tapping, reversing, and other operations. The purpose is to avoid repeated abrasive trajectories, achieve uniform grinding of the grinding tool and sealing surface, and improve the flatness and smoothness of the sealing surface.

　　3、检验阶段在研磨过程中始终贯穿着检验阶段，其目的是为了随时掌握研磨情况，做到心中有数，使研磨质量达到技术要求。应该注意的是，不同的阀门研磨时应使用适应各种密封面形式的研磨工具，以提高研磨效率，保证研磨质量。

　　3. The inspection stage runs through the grinding process, with the purpose of keeping track of the grinding situation at all times, achieving a clear understanding, and ensuring that the grinding quality meets the technical requirements. It should be noted that grinding tools suitable for various sealing surface forms should be used when grinding different valves to improve grinding efficiency and ensure grinding quality.

　　阀门研磨时一项很细致的工作，需要在实践中不断的体会、摸索、提高，有时研磨得很好，可是装上以后还是漏汽漏水，这是因为在研磨过程中有磨偏的想象，手拿研磨杆不垂直、歪斜，或是研具尺寸角度有偏差所致。由于研磨剂是磨料和研磨液组成的一种混合剂，而研磨液又仅是一般的煤油和机油。因此，正确地选用研磨剂关键的一环是正确地选用磨料。

　　Valve grinding is a very meticulous task that requires continuous experience, exploration, and improvement in practice. Sometimes the grinding is done well, but after installation, there is still steam and water leakage. This is because there is an imagination of grinding deviation during the grinding process, such as the grinding rod not being vertical or skewed, or the size and angle of the grinding tool being deviated. Due to the fact that abrasives are a mixture of abrasives and grinding fluids, and grinding fluids are only ordinary kerosene and engine oil. Therefore, the key to selecting abrasives correctly is to choose the right abrasive.

　　4、如何正确地选阀门研磨剂？氧化铝（AL2O3） 氧化铝又称刚玉，其硬度较高，使用很普遍。一般用来研磨铸铁、铜、钢及不锈钢等材料的工件。

　　4. How to choose valve grinding agent correctly? Aluminum oxide (AL2O3), also known as corundum, has high hardness and is widely used. Generally used for grinding workpieces made of materials such as cast iron, copper, steel, and stainless steel.

　　碳化硅（SiC） 碳化硅有绿色及黑色两种，其硬度比氧化铝高。绿色碳化硅适用于研磨硬质合金；黑色碳化硅用于研磨脆性材料及软材料的工件，如铸铁、黄铜等。碳化硼（B4C） 硬度仅次于金刚石粉末而比碳化硅硬，主要用来代替金刚石粉末研磨硬质合金，研磨镀硬铬的表面。氧化铬（Cr2O3） 氧化铬是一种硬度高和极细的磨料，淬硬钢精研时常常使用氧化铬，一般也用它来抛光。氧化铁（Fe2O3） 氧化铁亦是一种极细的阀门磨料，但硬度及研磨效果均较氧化铬差，用途与氧化铬相同。金刚石粉末 即结晶磮C，它是硬的磨料，切削性能较好，特别适用于研磨硬质合金。此外，磨料粒度（磨料的颗粒尺寸大小）的粗细对研磨效率及研后表面粗糙度有显著的影响。粗研时，阀门工件表面粗糙度要求不高，为提高研磨效率宜选用粗粒度的磨料；精研时研磨余量小，工件表面粗糙度的要求高，可采用细粒度的磨料。密封面粗研时磨料的粒度一般为120＃～240＃；精研为W40～14。?阀门调制研磨剂，通常是往磨料里直接加入煤油和机油。用1/3煤油加2/3机油与磨料调合成的研磨剂适用于粗研；用2/3的煤油加1/3机油与磨料调合成的研磨剂可用于精研。当研磨硬度较高的工件时，使用上述研磨剂的效果就不够理想。这时，可采用三份磨料加一份加热的猪油调合起来，冷却后形成糊状，使用时再适当加些煤油或汽油调匀。

　　Silicon carbide (SiC) comes in two types: green and black, and its hardness is higher than that of aluminum oxide. Green silicon carbide is suitable for grinding hard alloys; Black silicon carbide is used for grinding brittle and soft materials such as cast iron, brass, etc. Boron carbide (B4C) has a hardness second only to diamond powder and harder than silicon carbide. It is mainly used to replace diamond powder in grinding hard alloys and grinding surfaces coated with hard chromium. Chromium oxide (Cr2O3) is a high hardness and extremely fine abrasive commonly used for precision grinding of quenched and hardened steel, and is also commonly used for polishing. Iron oxide (Fe2O3) is also an extremely fine valve abrasive, but its hardness and grinding effect are inferior to chromium oxide, and its use is the same as chromium oxide. Diamond powder, also known as crystalline carbide, is a hard abrasive with good cutting performance, especially suitable for grinding hard alloys. In addition, the grain size of the abrasive has a significant impact on the grinding efficiency and surface roughness after grinding. During rough grinding, the surface roughness of the valve workpiece is not required to be high. To improve grinding efficiency, it is advisable to use coarse-grained abrasives; During precision grinding, the grinding allowance is small and the surface roughness of the workpiece is required to be high. Fine grained abrasives can be used. The abrasive particle size during rough grinding of the sealing surface is generally between 120 # and 240 #; Refined to W40-14.? Valve modulation grinding agent usually involves directly adding kerosene and engine oil to the abrasive. The abrasive prepared by mixing 1/3 kerosene with 2/3 engine oil and abrasive is suitable for rough grinding; A grinding agent prepared by mixing 2/3 kerosene with 1/3 engine oil and abrasive can be used for precision grinding. When grinding workpieces with high hardness, the effect of using the above-mentioned abrasives is not ideal. At this point, three parts of abrasive and one part of heated lard can be mixed together to form a paste after cooling. When using, some kerosene or gasoline can be added appropriately and mixed evenly.

　　5、研磨工具的选择阀瓣和阀座密封面由于损坏程度不同，不能直接对研，而是先用事先专做的一定数量和规格的假阀瓣（即研磨头）、假阀座（即研磨座）分别对阀座、阀瓣进行研磨。研磨头和研磨座用普通碳素钢或铸铁制做，尺寸和角度应与置于阀门上的阀瓣、阀座相等。研磨若手工进行，需配置各种研磨杆。研磨杆和研具要装配得当，不能歪斜。为减轻人的劳动强度，加快研磨速度，常采用电动研磨机或振动研磨机研磨。

　　5. The selection of grinding tools for valve discs and valve seat sealing surfaces cannot be directly ground due to different degrees of damage. Instead, a certain number and specifications of pre made fake valve discs (i.e. grinding heads) and fake valve seats (i.e. grinding seats) are used to grind the valve seat and valve disc respectively. The grinding head and grinding seat are made of ordinary carbon steel or cast iron, and the size and angle should be equal to the valve disc and seat placed on the valve. If grinding is done manually, various grinding rods need to be configured. The grinding rod and grinding tool should be assembled properly and not tilted. To reduce human labor intensity and accelerate grinding speed, electric grinding machines or vibration grinding machines are often used for grinding.