Operation and Maintenance Manual for Butterfly Valve - KEFA-VALVE

1. Safety Warnings and Precautions

1.1 General Warnings

• Please read this manual carefully before installation, operation, and maintenance. Improper use may result in equipment damage, personal injury, or property loss.
• Only qualified personnel (trained in valve operation and safety procedures) are permitted to perform installation, maintenance, or repair work.
• During operation, comply with local safety regulations, industry standards (such as EN 593 and API 609), and pressure vessel safety requirements.

Figure 1: Flange Butterfly Valve with electric actuator

1.2 Special Precautions

• Strictly do not exceed the maximum operating parameters (pressure, temperature, and medium compatibility) marked on the product nameplate. Butterfly valves with rubber seals are strictly prohibited from long-term operation under dry grinding conditions.
• Prior to any maintenance work, the valve must be isolated from the pipeline, pressure relieved, medium drained completely, and the absence of residual pressure or medium confirmed before proceeding with operations. If the medium is a corrosive fluid, additional pipeline cleaning is required.
• Wear appropriate personal protective equipment (PPE) such as safety goggles, acid-alkali resistant gloves, and protective clothing when handling the valve or coming into contact with hazardous media.
• During operation, do not place hands, tools, or foreign objects near moving components including valve stems and butterfly discs to prevent pinching or component jamming.
• Soft sealing materials (e.g., rubber) are sensitive to high temperatures and strong oxidizing media. Strictly follow the medium compatibility requirements to avoid aging and failure of sealing components.

2. Product Overview

2.1 Product Description

Butterfly valve is a type of valve with a simple structure and quick opening and closing. Its core component is a disc (valve plate) installed on the rotating shaft. When the valve plate rotates parallel to the pipeline, the valve is fully open and the fluid resistance is low; When rotated perpendicular to the pipeline, the valve closes to achieve truncation. It is widely used in pipeline systems such as water treatment, HVAC, petrochemicals, etc. due to its small size, light weight, and flexible operation, especially suitable for flow regulation and cutting in large diameter and low pressure drop situations.

The main components of butterfly valves are: valve body, disc, seat, shaft, and drive device

Figure 2: Components of Butterfly Valve

2.2 Butterfly Valve Details

• EPDM rubber: -20°C to 120°C, continuous operating temperature: 0°C to 100°C.
• At 130°C operating conditions, restrictions apply to liquid types; consult the manufacturer for confirmation.
• For special media conditions, consult the manufacturer for confirmation.

2.3 Technical Standard

3. Storage, installation, use, and inspection

3.1 Storage

• Store valves indoors in a dry, well-ventilated, dust-free and sun-protected environment.
• During prolonged storage, position the valve disc at a 10° angle to prevent permanent deformation of the elastic seat.
• Inspect valves every two months during storage.
• When handling coated butterfly valves, take care to avoid damaging the coating surface. Should damage occur, repair the coating promptly.

3.2 Installation

• The best position for installation in pipelines is upright installation, which cannot be inverted, and sufficient space for maintenance, inspection, and operation should be reserved.
• The flange should be selected according to EN 1092/ASME/AWWA or a special flange for butterfly valves (it is recommended to use a flat flange); And select bolts and nuts according to the corresponding standards and the length of the butterfly valve structure.
• Before installation, the valve cavity and pipelines need to be cleaned thoroughly, and there should be no foreign objects such as iron filings or welding slag in the sealing seat, valve disc, and pipelines.
• During installation, the valve should be slightly opened. When locking the bolts, they should be pre tightened diagonally and the connecting bolts should be tightened one by one to maintain balanced force and avoid damaging the valve seat; Do not use an extended arm wrench for operation.
• After installation, please rinse the valve repeatedly in the fully open position until the inside of the pipeline is completely cleaned before opening and closing the valve and the system.

3.3 Installation precautions

• When welding at the upper end of the same riser as the valve, please operate the valve to the fully open position to prevent welding slag and splashes from accumulating at the valve disc and damaging the valve seat rubber.
• After welding, the flange weld must be polished to remove welding slag and splashes, and it is not allowed to protrude above the flange sealing surface to prevent damage to the valve seat rubber.
• During on-site installation, please pay special attention to welding on the corresponding flange after the butterfly valve is installed in place to avoid damaging the rubber of the Butterfly Valve Seat.
• When installing valves, they should generally be positioned before pipeline installation to align the two flange holes and allow bolts to pass smoothly through the installation holes. Forced installation is prohibited.

3.4 Use

• Please ensure that the operating conditions of valve A are consistent with the information specified on the nameplate.
• During the operation of the system, the B valve should be operated in the direction and position indicated on the label.
• Please slowly turn the handle or handwheel to open and close the C valve, in order to avoid water hammer caused by rapid opening and closing, which may damage the pipeline system.

Figure 3: Installation diagram of different types of butterfly valves

4. Common faults and troubleshooting methods of butterfly valves

• When the Electric Butterfly Valve leaves the factory, the opening and closing stroke of the control mechanism has been adjusted. To prevent directional errors when the power is turned on, users can manually adjust the valve to the half open position before the first power is turned on, and check that the direction of the indicator wheel is consistent with the valveopening and closing direction by pressing the electric switch.
• When the worm gear butterfly valve runs for about two months, please open the worm gear box cover and check if the butter is normal.
• Please check that each connecting part requires compression to ensure the sealing of the packing and the flexible rotation of the valve stem.
• During the installation and use of the valve stem, please regularly check the effectiveness of the valve and promptly troubleshoot any faults found.

The possible faults and their elimination methods are detailed in the table below:

5、 Precautions
5.1 This valve design only considers general operating conditions. If there are special requirements, they must be specified in the contract;
5.2 This valve design only considers minor corrosion and is not suitable for situations with severe or special corrosion;
5.3 The working temperature of this valve shall not exceed the data in the performance table. Any consequences caused by exceeding (including instantaneous) this range shall be solely the responsibility of the user;
5.4 The applicable medium of this valve is listed in the performance table. Any consequences caused by exceeding this range are entirely the responsibility of the user;
5.5 When installing this valve, fluid turbulence and pressure fluctuations should be considered, and a location with uniform water pressure load should be selected for installation (generally set to a minimum of 5 times the pipe diameter). It is not recommended to use it in piping systems with pressure changes;
5.6 Valves shall not be disassembled under pressure;
5.7 During the repair process, the valve needs to be matched according to the material list of the parts;
5.8 The wall thickness of this valve has been designed with additional allowance and safety factor taken into account.