So you’ve got a globe valve that is no longer functioning correctly
(or at all) because of a broken linkage, leaky hydraulic actuator, non-functioning electric or pneumatic actuator. No need to throw the baby out with the bath water! Many valves can be retrofitted with new linkages and actuators, putting them back into service in as little as an hour. If the valve requires customized linkages, the process will take a bit longer. The good news is that most valves (assuming they have adequate service life left) can be retrofit, often with off-the-shelf kits that can be easily installed at the jobsite.
What You’ll Need For A Successful Retrofit
Precision is the key to a successful valve retrofit. This begins with taking careful measurements of the existing equipment and providing all of the proper installation and product information to the retrofit supplier. This process starts with the proper measurement equipment, preferably using a vernier caliper with a depth gauge or probe. Rounding off to the nearest 1/8 or 1/16 inch will not result in optimum performance. Belimo retrofit kits, for example, are typically within a ±.005” tolerance.
Make sure you have accurate recordings of all of the following to submit to your supplier:
Valve Details
- Valve style (i.e. internal packing nut, external packing nut, etc.) and the corresponding dimensions.
- Stem style and corresponding dimensions
- Valve model number, series, and manufacturer
- Is it a 2-way or 3-way valve?
- Is it a steam or hydronic valve?
- What is the system temperature and pressure?
Actuator Details
- Model number of existing actuator
- Control type (i.e. on/off, floating point, vdc, or pwm)
- Is the actuator fail safe
- Is the actuator for an indoor or outdoor application
It may seem like a lot of effort but remember that replacing a valve along with the actuator, or trying to determine how to fix a linkage, is not always practical. Furthermore, taking a system off-line to replace a valve assembly can have a cost impact that extends well beyond the the replacement itself. Retrofit solutions are, quite often, the most practical and cost effective solution.
Belimo Aircontrols has retrofit solutions for almost any globe, butterfly or ball valve application and can even build customized linkages for those valves which have no direct retrofit solution. If you are trying to work through any type of valve or damper actuator retrofit challenge, Belimo has an essential document which will carefully walk you through every step of the process from taking proper measurements to the installation of the new linkage.For instruction on how to retrofit, take free online training. Sign up now.