Case Study: Weir Plate Repair & Replacement

Weir Plate - Case Study


Our customer in the water authorities industry operate a disposal plant that manages sludge from various wastewater treatment processes. The plant utilises a sludge thickening tank equipped with a metal weir plate to facilitate settling sludge and the controlled release of clarified water back into the local watercourse.

Unfortunately, the existing weir plate suffered damage, potentially caused by a pump hose. The damage posed several operational issues, such as improper settling of sludge, inconsistent water flow, and a risk of further deterioration if not addressed promptly. As a temporary fix, one of the plant's process controllers fastened a makeshift piece to the damaged area to prevent further complications. However, this was not a sustainable solution and a proper repair was required to restore the weir plate to full functionality.

The water authority faced a strict constraint of only one day to replace the weir plate. Any delay beyond this window could disrupt the plant's wastewater treatment and sludge disposal operations, leading to potential regulatory non-compliance and environmental concerns.

The Solution

The chosen solution involved a comprehensive approach. Prior to the repair date, PAR experts conducted an on-site inspection to assess the extent of the damage and evaluate the replacement requirements. This assessment helped identify the materials, tools, and personnel needed for the project. Since the weir plate was a critical component for the sludge thickening process, ensuring the replacement piece precisely matched the original dimensions and specifications was essential. This was done by our representative, who created accurate dimensional drawings onsite.

From these drawings, we created accurate CAD drawings for the damaged plate, which can be reused if any of these need replacing again. The new plate was machined from black UHMW as opposed to metal, as the polymer is resistant to abrasion, chemicals, impact and wear. UHMW is also non-toxic, odourless, and highly resistant to moisture, making it a perfect material for this application. 

The plate was then delivered on the same day to the plant, and the plant staff got to work removing and replacing the original weir plate. The well-coordinated effort minimised downtime and optimised efficiency. Following the installation, the repaired weir plate underwent rigorous testing to confirm its structural integrity and functional performance, guaranteeing compliance with industry standards.

Key Features 

  • Manufactured wholly in-house.
  • CAD drawings are taken for ease of re-order.
  • Successfully replicated OEM parts.
  • Fast manufacturing and installation process.
  • Limited downtime on the production line.

Common Industries

Most commonly used in water industries.

To enquire about our plastic machining capabilities, please contact our sales team


The weir plate replacement project for the water authority's sludge thickening tank demonstrated the effectiveness of PAR Group in addressing urgent infrastructure challenges. Despite the time constraints, the project was completed successfully, restoring the efficient operation of the tank and ensuring continued compliance with environmental standards. This case study highlights the importance of timely and professional maintenance in water processing facilities to uphold operational excellence and environmental responsibility.

Weir Plate Case Study - Before
Weir Plate Case Study - After