Handling Production Failures in Filter Presses

The filter press is an indispensable dewatering solution for sand and gravel production lines. It effectively dehydrates wastewater for recycling, facilitating easier storage and transportation while saving time and energy. However, how do you diagnose the root causes of filter press failures and implement effective solutions? This article outlines common failure reasons and provides corresponding troubleshooting steps to help our customers maintain optimal performance.

Damage to the Frame Structure

Primary Causes

1. Excessively thick slurry or residual dry blocks can cause blockages at the feed port. When no material separates the filter plates, they are subjected solely to the pressure from the hydraulic system. Prolonged exposure to this condition makes the plates highly susceptible to damage.

2. Insufficient feeding or the presence of inappropriate solid particles in the feed can also lead to excessive force application, resulting in structural damage to the frame itself.

3. If the outlet is blocked by solids, or if the feed valve or discharge valve remains closed during startup, pressure cannot be released, leading to potential damage.

4. Inadequate cleaning of the filter plates may result in medium leakage. Once leakage occurs, the edges of the plate frames can become damaged with small grooves. Significant medium leakage prevents pressure buildup, thereby hindering the formation of mud cakes.

Approach

1. Carefully use a nylon cleaning scraper to remove mud from the feed inlet.

2. After completing this cycle, reduce the volume of the filter plates.

3. Thoroughly inspect the filter cloth for any issues. Additionally, verify that the drain port and outlet are clear and unobstructed; open the corresponding pressure valve to release pressure.

4. Carefully clean and repair the filter plates.

Water seepage between plates and frames

Main Reason

1. Low hydraulic pressure.

2. Wrinkles or gaps in the filter cloth. If detected, replace the filter cloth promptly.

3. Unknown objects resembling blocks are present on the sealing surface.

Approach

Correspondingly increase the hydraulic pressure, replace the filter cloth, or use a nylon scraper to remove unknown lumps from the sealing surface.

The formed filter cake is uneven or fails to form properly

Main Reason

The feed particle size is too small, the concentration is too low, the feed volume is insufficient, or the outlet is blocked, leading to uneven distribution of the filter cake and difficulty in forming a cohesive cake.

Approach

Adjust production processes, improve material supply by increasing or decreasing feed rates as needed, clear blockages, clean supply holes and drain holes, clean or replace the filter cloth, increase pressure or pump power, and initiate operation at low pressure with gradual pressurization.

Filter Plate Moves Slowly or Falls Off

Main Reason

Excessive oil and dirt on the guide rod can cause the filter plate to move slowly or even fall off, posing a significant safety hazard.

Approach

Timely clean the oil and stains from the guide rod and apply grease to ensure proper lubrication and prevent accidents. Strictly avoid using thin oil on the rod, as it increases the risk of the plate slipping and causing personal injury.

Insufficient Flow in the Hydraulic System

Main Reason

1. The oil pump is not delivering oil.

2. The sequence valve setting pressure is too low, or the valve core is stuck in the open position.

3. The oil filter is clogged.

4. The oil level in the tank is too low, causing the oil pump to draw air.

5. The hydraulic oil viscosity is too high, making it difficult for the pump to suction oil.

6. Severe wear on internal pump components results in excessive internal leakage, preventing the system from reaching rated pressure and flow values.

Approach

1. Overhaul the oil pump.

2. Overhaul the sequence valve.

3. Clean the oil filter.

4. Replenish the oil.

5. Change the oil or increase the oil temperature.

6. Repair or replace the oil pump.