Precautions for pressure testing of a Plug Valve
- Jan 10, 2020
- Hits: 197
1. When testing the pressure of the whole system, the plug valve should be kept in full open position, which means that the full open position shall remain unchanged after installation. Do not test the...
Dervos Valves in ECO FUEL INNOVATION PROJECT
- Jan 03, 2020
- Hits: 51
In 2017, we supplied 136 pcs of valves for the ECO FUEL INNOVATION PROJECT. This is a testing project of converting oil-wood chip to diesel, and Dervos is proud to be involved in this fuel innovation...
Single Piston Effect and Double Piston Effect Seats of Ball Valves
- Dec 18, 2019
- Hits: 5197
SPE (Single Piston Effect) seats are usually called self-relieving seats. Trunnion mounted ball valves with SPE seats are able to release over-pressure in cavity into pipeline automatically. ...
Brief introduction of V-TYPE BALL VALVE
- Dec 12, 2019
- Hits: 72
V-type ball valve is a kind of ball valve. Its closing part is a V-shaped opening on the ball. The V-shaped opening has a sharp edge. During the rotation of the ball, there is a wiping effect between...
The relation between Valve Size and Medium Flow Velocity
- Nov 27, 2019
- Hits: 57
1. The flow rate and flow velocity of the valve mainly depend on the diameter of the valve and the resistance of the structure of the valve to the medium. At the same time, they are intrinsically related...
What is a foot valve?
- Nov 21, 2019
- Hits: 69
Foot valve, also called bottom valve, belongs to a type of check valve. Different from other valves, a foot valve has a larger flow area than the pipe size, which is to prevent head loss of the pipe....
Opening of DERVOS INTEGRATION CENTER
- Nov 13, 2019
- Hits: 68
On Oct. 29th, a big opening ceremony of Dervos Integration Center was held in Lishui, Zhejiang. We invited our important customers to share this happy moment. The Integration Center will play an important...
Valves fire resistance test
- Nov 06, 2019
- Hits: 68
The petrochemical industry is one of the pillar industries of the national economy. Its production process is complex, and the raw materials, semi-finished products and finished products used in the production...
Features of Ball Valve
- Nov 01, 2019
- Hits: 80
The main features of the ball valve are their compact structure, reliable seal, simple structure, easy to repair. The sealing surface and the spherical surface are often in a closed state, not easy to...
The differences between soft seal and hard seal of butterfly valves
- Oct 23, 2019
- Hits: 242
For butterfly valves, hard seal means that both sides of the seal are made of metal material or other hard materials. The sealing performance of this seal is poor, but it is resistant to high temperature,...