Thomas Schulz, marketing manager at GEMÜ Valves, Inc, offers a comprehensive guide to designing, constructing and implementing multi-port valves.

Customer-specific multi-port valves are a modified version of conventional valve configurations consisting of 2/2-way valves and T-valves. They offer reduced dead space and clearance volume, they do not require an internal weld, and they are compact and
easy to install.

Complex processes and functionalities are still being implemented today, over 15 years after the introduction of the first multi-port valves into the market, often with elaborately welded constructions. The valves, fittings and pipe components used require a lot of space, serious mounting and often manual welding on-site, which involves an extensive validation process, not to mention the high hold-up volume and large amounts of dead space.

Due to their individual designs, multi-port valves, or M-blocks, can combine diverse functions, such as mixing, separating, routing, draining, feeding and isolating, in a small space. Safety functions, double shut-offs, cross connections and adjustment controls are also possible. These individual functions are assigned specific tasks depending on each case.

Good planning of valve technology begins in the project phase. The implementation of complex operational sequences requires compact valves that come in many different designs. GEMÜ, a German manufacturer and supplier of diaphragm valves, actuators and control systems, attaches great importance to providing customers with a block tailored to their specific application.

There are several points to consider when designing and constructing M-blocks: the application and process safety of the system into which the block is to be installed; the function of the block; the number, dimensions and function of the pipe connections; the number and size of the valve seats; the mounting position and draining direction of the block; the required space; the actuator type and function; and the type of material.

Planning and partnerships

It is often said that ‘failing to plan is planning to fail’. The costs that may arise from errors in the planning of production systems justify increased planning time and expenditure. Delays and extra cost during validation, delayed startups, contaminated batches and last-minute changes to the system are just a few of the arguments to support such planning. M-blocks reduce process risks in the system. Experience has shown that the costs of removing a faulty welding configuration and belatedly replacing it with an M-block are several times greater than the already high procurement costs. At the same time, timely and thorough planning reduces extra costs and keeps delivery times to a minimum.

In order to make processes safer, increase the operational availability of the system and reduce the life-cycle costs of a system within the framework of a total cost of ownership concept, more than 400 different designs and thousands of customer-specific variations of multi-port valves have been created over the years at GEMÜ.

GEMÜ supports its customers with ideas and initial designs, starting with the development phase. Next, the designs are constructively implemented into the 3D CAD system, adjusted in collaboration with the client and processed in a powerful machine outfit.

Every year thousands of blocks, ranging from 100g to 500kg per unit, are manufactured in eight multi-axial processing centres. Up to five new customer-specific block variants, on average, are generated in the design centre each day. Anything that clients propose, GEMÜ will try to make a reality.

Advantages of M-blocks:

  • Customer-specific construction and flexible design
  • Compact design so minimal space is required
  • Low hold-up volume and minimal wetted surface
  • Reduced dead space
  • Optimum draining
  • Machined from a single material block
  • CIP and SIP-suitable design
  • No internal welds, so shorter cleaning times
  • Fewer fittings, welds and X-ray examinations
  • Standard welded ends for orbital welding, as well as clamps
  • Compatible with actuators and diaphragms from the proven GEMÜ advanced modular system
  • Shortened and simple validation
  • Increased product safety
  • Reduced total cost of ownership