In short: seawater destroys ordinary valves by corrosion, and large transmission lines destroy them by water hammer. A rubber-lined, double-eccentric butterfly valve answers both. BTGC supplies Nakakita Seisakusho Co., Ltd. butterfly valves up to 3000 mm for desalination and water transmission.
Saudi Arabia moves more seawater than almost any country on earth. Every desalination plant on the Gulf and the Red Sea takes in seawater through intake lines, passes it through pumps and membranes or evaporators, and sends potable water inland through pipelines that run for hundreds of kilometres. At every point a valve isolates, regulates or protects the line, and seawater attacks each one.
Two problems in one valve
Corrosion. Gulf seawater is warm and highly saline. Unprotected carbon steel pits within months; even some stainless grades suffer crevice corrosion. The valve seat and disc edge, where flow is fastest, go first.
Water hammer. When a pump trips or a valve closes too fast on a long line, the column of water keeps moving and then reverses. The pressure spike can crack valve bodies and lift pipe supports.
What a seawater butterfly valve needs
| Feature | Why |
|---|---|
| Rubber lining on body and seat | Isolates the metal from seawater; the disc seals on rubber, not metal |
| Double-eccentric disc | The disc lifts off the seat as it opens, so the rubber lasts for thousands of cycles |
| Corrosion-resistant disc material | Aluminum bronze, duplex or coated ductile iron depending on the duty |
| Slow-closing actuator or hydraulic control | Closes over a set time to stop water hammer |
| Large sizes | Intake and transmission lines run from 1000 mm to 3000 mm |
Nakakita valves from BTGC
Nakakita Seisakusho Co., Ltd. of Japan has built valves and fluid control systems since 1930. The range BTGC supplies in the Kingdom covers:
Concentric and double-eccentric rubber-lined butterfly valves for seawater and utility service, up to 3000 mm
High-lift safety valves for boiler and steam protection
Remote control systems: hydraulic power units and consoles to operate valves in inaccessible places
Cargo handling valve systems for liquid loading and unloading
In the Kingdom these valves serve desalination intake and outfall, water transmission lines and tank farm automation. See the range on our page for Nakakita valves in Saudi Arabia and the full industrial valves offer.
Non-slam check valves complete the line
A butterfly valve regulates and isolates; a non-slam check valve protects the pump when flow reverses. BTGC supplies both, so a pumping station can be specified as one package. Ask for the surge analysis with the valve offer on any long transmission line.
BTGC support in Dammam, Jubail and Yanbu
BTGC supports power and water utilities across the Kingdom from Dammam on the Gulf and Yanbu on the Red Sea, with the service center in Jubail for valve testing and repair. For a quotation send the line size, pressure rating, fluid (seawater, brine or potable), the actuation required and the closing time.
Questions buyers ask
Rubber lining or coating? A bonded rubber lining is thicker and resists abrasion from sand in the water; a coating is for lighter duty.
What closing time stops water hammer? It depends on the line length and velocity. BTGC can arrange a surge study for the pumping station.
Are spares held in the Kingdom? Seats and seals for common sizes are stocked; ask for the current list.
Contact the BTGC valve team
Email valves@btc-ksa.com or call +966 13 856 0528. Branches: Dammam, Jubail and Yanbu. Request a quote.