A case-study on the importance of correct valve alignment.


Large Spanish Oil Refinery


Avoid spillage and contamination during loading operations from their tank farm


  1. Valve Actuators
  2. Valve Position Indicators (VPI)


A large Spanish refinery operates its own tank farm for petrochemical storage. Each tank contains different types of product. Incorrect valve alignment had resulted in the accidental loading of incorrect product into the process.

Previously, misalignment of manual valves had resulted in loading of incorrect products onto a barge. Since this was only discovered after the vessel left port, it had to return to be emptied, cleaned and refilled, resulting in expensive clean-up costs, inefficient labour and costly vessel downtime.

A solution was required for 1,100 manual valves, in order to avoid a repeat of this incident

A common solution would be to install actuators to each valve. These can be programmed, such that misalignment is impossible, as they clearly indicate the position of each valve in the control room. Additionally, operators would no longer be required in the field to operate the many valves manually. This was however irrelevant to this customer, as company policy required manual valve operation in many cases. Also, the CAPEX expense for installing 1,100 actuators was extremely high.

Position indicators for multi-turn valves are hard to come by

Aside from actuators, finding alternative methods of valve position indication of their multi-turn, manual valves proved difficult. Although 90° switchboxes are readily available, reliable solutions for multi-turn valves are hard to find.

Thorough field-testing proved Valve Position Indicators (VPIs) to be the best position indicator available

After an extensive search, several alternatives were piloted for a period of over two years. By the end of that period, the Netherlocks Valve Position Indicator proved to be the most reliable position indicator available in the market. With VPI, the company found a highly cost effective but state of the art alternative to actuators. By installing the VPI on all manual valves in the tank farm, the costs were one quarter of what was required to install actuators. With this, the position of each manual valve became visible in the control room, giving the operators a good overview of the alignment of the array of valves in the field before starting loading operations.

VPI offered 75% CAPEX savings compared to Actuators

Shortly after installation, the VPI proved its worth. It enabled the operators to discover an accidental valve misalignment. Loading was therefore delayed whilst the issues was resolved, thus avoiding delays and unexpected costs.


  1. 75% savings in CAPEX
  2. Timely signalling of misalignment
  3. Avoiding of unanticipated clean-up costs

To learn more about Netherlocks Valve Position Indicators and how they can benefit your equipment, please contact us. Avenium Engineering are the exclusive agent and distributor for both Netherlocks and Smith Flow Control in the UK, please take a moment to view Avenium Engineering’s full range of Product and Service offerings.