过程排放分析中波纹管泵的应用（中英文）

可靠的气体分析和快速响应时间通常需要使用采样泵。在市场上可用的类型中，波纹管泵原理特别耐用且维护成本低。选择型号的标准主要取决于它是防爆还是安全区域应用以及所需的流量。带有集成不锈钢旁通阀的特殊版本还可以简化管道。

还有一些气体分析应用不需要采样泵，即如果过程中存在足够高的过压，并且分析仪可以安装在非常靠近工作的位置。在所有其他情况下，作为分析系统一部分的采样泵是精确测量的先决条件，特别是在需要较短响应时间的情况下。当谈到超压时，这听起来微不足道：如果没有超压，就没有气体流向分析仪。这通常需要供应约 60 l/h 的样气。在许多超压应用中，仍然需要泵在足够短的时间内将样气从气体采样点输送到分析柜。超过 50 m 的线路长度在这里并不罕见。因此，如果待分析的气体没有以足够的体积流量经由泵输送到分析仪，则可能会延迟很长的时间到达分析仪。

Reliable gas analysis with fast response times often requires a sample gas pump. Among the designs available on the market, the bellows pump principle is particularly durable and low maintenance. Criteria for choosing a model focuses heavily on whether it is an Ex or safe area application and the desired flow rate. Special versions with an integrated stainless steel bypass valve will also ensure an easier tube installation.

There are also gas analysis applications in which a sample gas pump is not necessary - namely if there is a sufficiently high overpressure in the process and the analyzer can be installed very close to the process. In all other cases, a sample gas pump as part of the analysis system is a prerequisite for accurate measurement, especially if short response times are required. When it comes to overpressure, this sounds trivial: without overpressure, there is no gas flow to the analyzer. The analyzer usually only needs a supply of around 60 l/h of sample gas. However, for many overpressure applications, a pump is required that transports the sample gas from the gas extraction point to the analysis cabinet in a sufficiently short time. Pipe lengths of over 50 m are not uncommon here. The gas to be analyzed may therefore reach the analyzer with a significant delay if it is not pumped there with sufficient volume flow.

最短响应时间

Minimal response times

在许多过程压力不足的应用中，流量为 400 Nl/h 的采样泵可确保响应时间短且过程易于调节。高流速意味着即使电缆长度较长也可以实现较短的响应时间，例如安全相关过程测量或排放测量所需的电缆长度。

选择泵时的第二个重要标准是应用领域。如果泵安装在安全区域并且还泵送非爆炸性气体，则可供选择的型号非常多。在潜在爆炸区域中的应用存在限制。特殊型号也适用于泵送易燃气体，但不得安装在危险区域。对于一些有机会将泵安装在安全区域的用户来说，这里有节省成本的潜力。

Measuring gas pumps with flow rates of 400 Nl/h ensure that the response time is short in numerous applications with insufficient process pressure, so that the process can be easily controlled. The high flow rates mean that short response times can be achieved even with long line lengths, such as those required for safety-relevant process measurements or emission measurements.

The second important criterion when selecting a pump is the area of application. If the pump is installed in a safe area and also pumps non-explosive gas, the selection of available models is very large. There are restrictions for applications in potentially explosive areas. Special variants are also suitable for pumping flammable gases, but must not be installed in the Ex area. This offers potential savings for some users who have the option of installing the pump in a safe area.

冷凝水：隔膜的敌人

Condensate: the enemy of the membrane

对于隔膜泵，始终存在冷凝水溶解所用粘合剂的风险，这意味着需要进行维护。另一方面，一体式 PTFE 波纹管面对面连接到泵头，无需额外的密封件。如果预计会形成冷凝水，则泵在出厂时可以转动泵头。如果在分析操作期间证明有必要，耐用的设计还允许客户只需几步即可自行转动泵头。然后气体连接指向下方；冷凝水可以毫无问题地去除——重力有帮助。

With diaphragm pumps there is always the risk that condensate will dissolve the adhesive used, making maintenance necessary. The PTFE bellows, on the other hand, is made from a single piece and is connected to the pump head face to face without an additional seal. If condensate formation is to be expected, the pump can be delivered from the factory with the head rotated. The durable design also allows the customer to rotate the pump head themselves in just a few steps if it proves necessary during analysis. The gas connections then point downwards; condensate can be easily drained away - gravity helps.

旁通阀由 PTFE 或不锈钢制成

Bypass valve made of PTFE or stainless steel

许多泵型号都可以配备集成旁通阀。当设计分析测量点时，可以省去外部旁路。到目前为止，这些旁通阀都是由 PTFE 制成的，这是首选的变体，特别是对于腐蚀性气体，可以防止腐蚀。 400 Nl/h 和 800 Nl/h 输送能力的泵型号的一项创新是不锈钢旁通阀的设计，仅适用于轻微腐蚀性气体。经验表明，当使用 PTFE 变体进行管道输送时，经过一段时间并反复拧紧软 PTFE 中的不锈钢螺钉连接后会发生泄漏。使用带有不锈钢旁通阀的泵体可以避免这种情况。

适当的维护当然是必要的，但对于波纹管泵来说，维护工作基本上减少到波纹管和泵阀上。必须定期检查它们，必要时进行更换。指定间隔的维护计划对 Atex 泵具有约束力。为了安全应用，维护间隔在很大程度上取决于相应的工艺和环境条件以及气体成分。通常，应在大约 4,000 个运行小时后或每六个月检查一次波纹管。对于所有泵，客户只需几个简单的步骤即可自行更换所有易损件。更换任何旁通阀的波纹管、入口阀和出口阀以及 O 形圈既快速又简单。如有必要，柱塞和带有滚珠轴承的偏心轮（即所谓的曲柄传动装置）可作为一个完整的组件完全更换。这意味着泵可以运行很多年；仅具有防爆认证的版本必须由制造商在几年后根据维护计划进行检查。

Many of the pump models can be equipped with an integrated bypass valve. When designing the analysis measuring point, an external bypass can then be dispensed with. Until now, these bypass valves were available made of PTFE - a variant that is the first choice, especially for aggressive gases, to prevent corrosion. An innovation in the pump models with 400 Nl/h and 800 Nl/h flow rate is the design of the bypass valve made of stainless steel, which is only suitable for less corrosive gases. Experience shows that when piping the PTFE variant, leaks develop in the soft PTFE after some time and after tightening the stainless steel screw connections several times. This can be avoided with the pump body with a stainless steel bypass valve.

Of course, proper maintenance is essential for this, but with bellows pumps this is essentially reduced to the bellows and the pump valves. They must be checked regularly and replaced if necessary. The maintenance plan with the specified intervals is mandatory for Atex pumps. For safe applications, the maintenance intervals depend heavily on the respective process and ambient conditions as well as the gas composition. Typically, the bellows should be checked after around 4,000 operating hours or every six months. The customer can replace all wearing parts in all pumps themselves in just a few steps. Changing the bellows, inlet and outlet valves and the O-ring of any bypass valve is easy and quick. If necessary, the tappet and eccentric with ball bearing - the so-called crank drive - are completely replaced as a complete assembly. This means that the pump can be operated for many years; only the versions with Ex approval have to be checked by the manufacturer after a few years in accordance with the maintenance plan.