From the specification sheet to the custom ball valve
In a large proportion of industrial installations, a standard valve meets the required service without difficulty. The valve type, pressure class, body and seat materials are selected, and the solution operates for years without major complexity. However, there are situations in which the catalogue shows clear gaps: the valve must operate outside usual ranges, fit into a space no one originally designed for it, or perform functions not contemplated in a series model. It is in this scenario that a custom ball valve makes sense, designed directly from the process specification.
At FHT Valves, these types of projects are approached as full engineering work. The goal is not to “force” a standard model, but to build a solution that responds precisely to the installation’s requirements.
When the catalogue is no longer enough
The first indication that a standard valve may not be sufficient usually appears in the data sheet itself. The combination of fluid, pressure, temperature and operating regime does not fit well within conventional tables. It may involve a high-temperature process gas, a service with large thermal variations, a line subject to very frequent operations, or an isolation point where, in the event of leakage, there is significant risk to safety or the environment.
Sometimes the issue lies not so much in the service as in the location. In an existing plant, it is common to find flange-to-flange distances that do not match any standard dimension, branch connections placed very close together, sharp direction changes, or equipment installed with minimal tolerances. Fitting a “catalogue” valve may require modifying piping, supports and insulation, with direct impact on cost, schedule and permits.
There are also cases in which the valve must perform several functions at the same time. A reactor bottom requiring complete discharge and proper drainage, a product line that must allow CIP cleaning without retention zones, or a double block and bleed arrangement to be solved within a single body are common examples. Connecting valve after valve and adding accessories may work on paper, but it multiplies potential leak points, complicates maintenance and penalizes available space.
In all these scenarios, a standard valve is an approximation, not a complete answer. The real solution lies in adapting the valve to the process and the plant, not the other way around.
From specification to valve concept
The design of a custom ball valve always begins in the same place: the service specification. Beyond basic pressure and temperature values, the type of fluid, operating regime, start-up and shutdown phases, expected cycles, applicable standards, required leakage class and automation requirements are analyzed. At the same time, the physical environment is studied: available space, connection type, accessibility, interference with other equipment, and assembly or disassembly needs.
With this set of data, the valve concept is defined. At this stage, decisions are made as to whether the solution should be floating ball or trunnion mounted, whether the internal configuration will be two-way, three-way, tank bottom, double block and bleed, or a specific combination, and which seat philosophy makes the most sense: soft seat to maximize tightness, metal-to-metal for severe service, PMSS to combine both, or spring-energized seats when the valve must operate across wide pressure and temperature ranges.
The result of this phase is not yet a drawing, but a clear architecture of the equipment: how it will isolate the line, how it will drain, how it will be cleaned, and how it will integrate with the actuator and control system.
Detailed engineering and validation
Once the concept is defined, the process moves on to detailed engineering. The valve is modeled in 3D, dimensions and tolerances are established, surface finishes and treatments are defined, thicknesses are calculated, the stem is sized, and the mechanical capacity of the assembly is verified against pressure, temperature and operating loads.
At the same time, the interfaces with the pipeline, the actuator and the instrumentation accessories are designed. The objective is not only for the valve to meet service requirements on paper, but also to physically fit within the installation, to be assembled and disassembled with the available means, and to allow reasonable maintenance throughout its service life.
This phase produces certified drawings, the bill of materials, and the inspection criteria that will accompany the manufacturing and testing process.
Manufacturing, testing and documentation
The next step is manufacturing: casting or forging of the bodies, precision machining, assembly of balls, seats and packings, application of coatings where required, and integration with the selected actuator. Each stage is controlled according to the criteria defined during detailed engineering.
Before delivery, the valve undergoes the tests specified: hydrostatic and pneumatic tests, leakage verification according to the applicable standard, functional operation tests, and, where necessary, additional checks associated with safety requirements or the type of fluid. All of this is documented through material certificates, test reports and technical documentation that allow the valve to be integrated into the plant’s management system.
The role of FHT Valves in custom projects
For FHT Valves, the development of custom ball valves is a natural extension of standard valve design, not an exception. Each project is approached with an engineering mindset: starting from the specification, building a coherent valve concept, and carrying out detailed engineering, manufacturing and testing with full traceability.
When a standard valve no longer meets service requirements, the alternative does not have to be complicating the installation with improvised solutions. A custom valve, designed from the specification sheet to the final product, aligns reliability, safety and life-cycle cost. If it is necessary to evaluate this option at a specific point in your installation, the technical team at FHT Valves can help transform the specification into a defined, verifiable valve solution ready to operate under real plant conditions.