General • Inspections

Flap Gate Maintenance

Maintenance and repair downtime is inevitable, but unintended downtime is expensive. Every minute of it is directly reflected in the bottom line. Fortunately, when it comes to belt drives, unplanned production standstills can often be prevented by taking the right approaches to inspection, maintenance and replacement.

MaintainX

07/28/2022

Flap Gate Maintenance

Field Cleaning and Painting

Fresno Valves' standard paint system on Flap Gates is commercial grade blast and Hi-build epoxy paint. It does not require top coating.

Should blast cleaning be needed to condition the gate for top coating, the gate should be fully closed and any exposed metallic seating faces protected from blast and paint. Before painting, blow all grit off gate, particularly in and around the seating faces.

Fresno Valves does not usually recommend removing the gate from the frame to apply finish/top coats because of the risk of damage to the seating faces during handling. If sufficient reasons exist for removal of the gate, (e.g., badly deteriorated paint or a complete change of paint system that is incompatible with the existing paint) then completely disassemble and thoroughly blast clean all surfaces to obtain a quality recoated product.

When disassembling the gate or gates, keep parts segregated and match-marked so that parts are not mixed gate-to-gate because interchangeability between gate parts is not always certain. Protect all seating surfaces on the gate and frame with duct or masking tape. Use special care in handling the gate to avoid damage to the seating faces.

Blast clean and paint the gate as required by the specifications or the paint manufacturer's recommendations. Do not paint the contact faces of the seat. Remove masking tape or other material used to protect machined faces. Clean all faces thoroughly and relubricate.

With the gate in the fully closed position, recheck maximum clearance between the seating faces with .004-inch thickness feeler gauge. Readjust, if required, per the instructions in this Manual.

Lubrication

Pivot Points

Lubrication of pivot points on Fresno Valves Flap Gates is usually not necessary. The construction of the hinge assembly permits only a few degrees of rotation at the bottom pivot points. The gate cover rotates about the upper pivot points through an arc of 90 degrees or less. With this limited rotation, lubrication of bushings is usually not needed nor normally recommended by Fresno Valves. When lubrication of flap gate pivot points is desired, a permanently lubricated bushing is installed at the factory o

Seating Faces

Periodically clean the gate seating faces and apply a light film of water-resistant lubricant to the seating faces. Lubricants such as Lubriplate's No. 630AA or 630AAA, Texaco's Multi-Fak Heavy Duty No. 2, or Shell Oil Company's Alvania No. 1 have been found satisfactory for this purpose.

Maintenance Schedule and Lubrication Summary Flap Gates

Source: MaintainX (Community Member)