Lianggong Valve mainly sells the following types of valves:

1. 球閥：球閥由球體和閥座構成，通過旋轉球體來控制流體的開關。球閥具有結構簡單、密封可靠、操作靈活等特點，廣泛應用于石油、化工、天然氣、水處理等行業。

1. Ball valve: The ball valve is composed of a ball and a valve seat, which controls the fluid switch by rotating the ball. Ball valves have the characteristics of simple structure, reliable sealing, and flexible operation, and are widely used in industries such as petroleum, chemical, natural gas, and water treatment.

2. 閘閥：閘閥通過提升或降下閘板來控制流體的通斷。閘閥具有啟閉快、流阻小、密封可靠等特點，適用于管道中需要頻繁啟閉或對流阻要求較低的場合。

2. Gate valve: The gate valve controls the flow of fluid by lifting or lowering the gate plate. Gate valves have the characteristics of fast opening and closing, small flow resistance, and reliable sealing, making them suitable for situations where frequent opening and closing or low flow resistance requirements are required in pipelines.

3. 截止閥：截止閥通過升降閥芯來控制流體的通斷。截止閥具有密封性能好、流阻小、啟閉力矩小等特點，在一般工況下都能滿足要求，被廣泛應用于各個行業。

3. Stop valve: The stop valve controls the flow of fluid by lifting and lowering the valve core. Globe valves have the characteristics of good sealing performance, small flow resistance, and small opening and closing torque, which can meet the requirements under general working conditions and are widely used in various industries.

4. 蝶閥：蝶閥由閥體、閥桿和蝶板組成，通過旋轉蝶板來控制流體的通斷。蝶閥具有體積小、重量輕、啟閉迅速等特點，廣泛應用于給排水、空調、暖通等系統中。

4. Butterfly valve: A butterfly valve is composed of a valve body, valve stem, and butterfly plate, which is rotated to control the flow of fluid. Butterfly valves have the characteristics of small size, light weight, and quick opening and closing, and are widely used in systems such as water supply and drainage, air conditioning, and HVAC.

5. 止回閥：止回閥用于防止介質倒流，具有自動封閉、啟閉迅速等特點。止回閥廣泛應用于石油、化工、電力、冶金等行業中，保護管道和設備的安全運行。

5. Check valve: Check valve is used to prevent medium backflow and has the characteristics of automatic sealing and rapid opening and closing. Check valves are widely used in industries such as petroleum, chemical, power, and metallurgy to protect the safe operation of pipelines and equipment.

除了以上幾種常見的閥門，良工閥門還銷售其他類型的閥門，如調節閥、安全閥、排氣閥等，以滿足不同行業的需求。

In addition to the common valves mentioned above, Lianggong Valve also sells other types of valves, such as regulating valves, safety valves, exhaust valves, etc., to meet the needs of different industries.