Dervos成功通过了美国石油研究所（API）发布的API-6D认证，今天证书已被授予Dervos，这是我们资格的另一种升级！为了实现与客户的更深入的合作，并进一步满足客户的不断增加的需求，Dervos一直不断努力提高我们的产品质量和生产力，为客户提供更好的产品和服务。我们期待着与客户合作，实现双赢！API认证API是美国石油研究所（API）的缩写，该公司于1919年成立，是美国第一家国家商业协会，以及世界上最早，最成功的标准制定的商人之一。该组织基于行业的特点和行业本身的需求。API代码于1924年开发，提供技术规范，以指导与石油工业相关的产品的生产。由于API组织开发的API代码的先进，普遍和安全性，以及世界石油行业的扩大影响，世界各国已广泛采用。因此，API组织最初是为了成为美国石油行业的学术组织，现在已经发展成为跨越国界的石油行业的权威学术组织。

晶圆凸耳蝴蝶阀的蝶形板安装在管道的横截面。在蝶形阀体的圆柱通道中，盘形蝶形板绕轴线旋转，旋转角度在0°和90°之间，并且当旋转到90°时，阀门完全打开。凸耳型蝶阀结构凸耳型蝶阀连接在两个管道凸缘，双头螺栓之间。其结构简单，体积小，重量轻，仅由几个部分组成。通过旋转90°，可以快速打开和关闭，阀门具有良好的流体控制特性。当蝶阀处于完全打开位置时，蝶形板的厚度是介质流过阀体时的唯一电阻，因此通过阀门产生的压降小，因此具有良好的流量控制特性。双偏移蝶阀具有两种类型的密封，弹性密封和金属密封。对于弹性密封阀，可以在阀体上设定密封件或附接到蝶形板周边。凸耳型蝶阀蝶阀的应用不仅广泛应用于石油，天然气，化工，水处理等的一般行业，而且还用于热电站的冷却水系统。用于硫酸工业中的气体管道：炉子前鼓风机入口和出口，继电器风扇入口和出口，电雾消除串联和耦合阀，S02主鼓风机入口和出口，转换器调节，预热器入口和出口等。调节和 cut off gas volume use. It is used for sulfur burning, conversion, dry suction section in sulfur acid system, and is the preferred brand of valve for sulfur acid device, and is considered by the majority of users as a butterfly valve with good sealing performance, light operation, vice corrosion, high temperature resistance, easy operation, flexibility, safe and reliable use, and has been widely promoted and used. Lug type butterfly valve is also widely used in: chemical, petrochemical, smelting, pharmaceutical, food and other industries in SO2, steam, air, gas, ammonia, CO2 gas, oil, water, brine, lye, seawater, nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid and other media in the pipeline as a regulating and intercepting device use. Structural features of lug type butterfly valve ①The unique design of three-way eccentric makes the sealing surface frictionless between the transmission, which prolongs the service life of the valve. ②Resilient seal generated by torque. ③The ingenious wedge design makes the valve have the automatic sealing function of tightening the more it is closed, with compensating and zero leakage between the sealing surfaces. ④Small volume, light weight, light operation and easy installation. ⑤Pneumatic and electric devices can be configured according to user requirements to meet the needs of r...

为了更好的管理各部门的工作，促进部门间的合作，提高工作效率，德沃斯于4月1日正式发布了公司ISO体系文件- dv -程序文件，新ISO体系文件共包含31个规范文件，涵盖了公司现有部门的全部内容。这些文件为德沃斯如何以更周到和有效的方式管理生产和服务客户提供了指导和要求。德沃斯阀门开拓市场十余年，坚持将更优质的产品推向市场。在疫情冲击下市场环境低迷的情况下，我们仍在寻求和改进，希望更好地为客户服务。

用于水的止回阀需要考虑的因素与其他阀门的选择一样多。与其他各种介质一样，水也有它自己独特的特性曲线，应该适应在这些介质中特定使用的阀门。当然，这是一个简单的问题，但当涉及到为水选择一个完美的止回阀时，可能包括一些不太明显的原因。水锤:虽然这种液压问题可以在其他流体中发现，但当介质被迫停止或突然改变方向时，水锤就会发生冲击。当水或其他介质被困在管道中，只能从两个方向通过时，管道就会产生振动和恼人的噪音。两者都损害了体制。在无数的应用中，输送水是一件很平常的事情，但在今天，它仍然是一个难题，因为几乎不可能保持水流无限稳定。水锤最常见的原因是泵在没有任何警告的情况下停止工作。水会回流到泵中，因为止回阀的反应不够快。水锤有时也指水击。反向流动:如果不加控制，水或任何介质的反向流动会使泵向后旋转，造成意外损坏。 Likewise,if water flows in the wrong direction, for any length of time, it will hurt the entire system seriously. Unlike a back flow preventer, which consist of, work in andem with multiple check valves, a single check valve is not a panacea. Valve chatter: Valve chatter occursif valves open and close constantly and frequently. Valve chatter can cause damage to the valve and piping and can inflict total failure to the system. Checking for water problems Though check valves areremarkable reliable and endless new model and design are brought to the field every year, all problems theytry to answer to are just these three listed above. Due toits simple structure, it can be immune from external factorslike power failure, but is still affected by flow direction, and by check valve design features and defects. There are two basic designs of check valves. One uses a disc (basically a flap) and one uses a free floating ball. They both have a single direction, which means that their job is to prevent water from flowing backwards through the pipe. Both types have advantages and disadvantages, but perform the same job with fairly equal success.Ultimately, however, the success of a check valve rest with an not-too-fast-or-too-slow action. Finally, like most valves, its sealing performance determines the success of a check valve . All of these things should be taken into account when selecting a check valve.

止回阀是指其启闭部分依靠介质的流量和力来移动，防止介质回流的一种阀门。止回阀作为一种自动阀门，主要用于介质在管道上单向流动，只允许介质单向流动。流体在压力下使阀瓣打开，从进口侧流向出口侧。当进口侧压力低于出口侧时,阀瓣自动关闭流体压力的作用下一个止回阀根据其结构特点可分为对夹式止回阀,升降式止回阀、旋启式止回阀,平衡锤止回阀等。对夹式止回阀与旋启式止回阀相比，流动阻力大，对夹式止回阀不适用于高压(Class900及以上)泵和压缩机的出口;不适用于脉动介质条件;不适用于氧气条件。2.由于WAFER结构，WAFER止回阀不适用于大口径(DN600及以上)、高压(Class900及以上)场合。3.对夹式止回阀应尽量水平安装。 In case of vertical pipeline, make sure the media flowfrom top to below. Lift check valve 1. Subject by the working principle,lift check valve can only be installed in the horizontal pipeline. 2. Compared with the swing check valve,its flow resistance is large,lift check valve is not suitable for large diameter (DN50 and above) occasions, in general,it’s suitable for DN40 and smaller application. Swing check valve 1. Swing check valve should as far as possible installed horizontally. In case of vertical pipeline, make sure the media flow from top to below. 2. limited by the structure,swing check valve should not be used for DN40 and below on the pipeline. 3. For large diameter pipelines (e.g. DN400 and above), Tilting swing check valves are recommended. Counter weight check valve 1. Choose according to needs 2. Counter weight check valveis used inwhere serious water hammer may occur.

俗称手动蝶阀，带杠杆的蝶阀和带齿轮箱的蝶阀都是需要手动操作的阀门，但两者在使用上仍有区别。1.手动蝶阀的杠杆直接驱动阀板，切换迅速，但费力;齿轮箱蝶阀通过齿轮箱驱动阀板，切换缓慢，不费力。因此，当管道内压力较大时，使用手柄蝶阀会特别费力，德沃斯建议您选择变速箱蝶阀。2.在工程项目中，首选齿轮箱蝶阀。因为除了节省人工外，它的密封性能也优于手柄式蝶阀，特别是在需要频繁切换的工况下，变速箱蝶阀会有更长的使用寿命。3.手柄式蝶阀一般多采用小直径(DN200以内)，因为小直径蝶阀扭矩小，可以直接用手开启和关闭，而齿轮箱式蝶阀采用齿轮箱驱动阀杆，更省力。 When the torque of the valve stem is greater than 300N-M, use the gear box drive, otherwise, the handle drive.