B series Actuator and Features

ACHEM B series big-size pneumatic actuators are specically designed for use with large quarter-turn valves. The symmedtrical design of racks & pinion structure of the product offered by us ensures that our actuators match the operational characteristics of plug, ball or buttery valves; or any device requiring precise and reliable 90° rotary motion. The B series large-size pneumatic actuators have enormous output torque and can operate normally even in extremely cold environments as low as -60 degrees Celsius. For the spring return version, the output torque range from 5500Nm to 45,000Nm. For the double acting version, the output torque range from 21,100Nm to 110,500Nm at 5 bar.

The B series big-size pneumatic actuators adopt a rack & pinion structure, which not only operates smoothly with high output torque but also features linear torque characteristics. For double-acting actuators, the output torque remains constant over quarter-turn stroke.

◎Symmedtrical design & Balanced installation & long working life

Symmetric design is the primary concept adopted by the B series big-size pneumatic actuators, whether in the dual piston symmetric design of the rack and pinion structure or the symmetric configuration of the left and right end caps. This design ensures balanced installation between the actuator and the valve, resulting in even force distribution and significantly extending the service life of the control valve.

The working modes of the B series big-size pneumatic actuators are single-acting or double-acting. Single-acting actuators use cartridge pre-compression springs, offering flexible configuration (users can configure the number of springs as desired). For one actuator size, suitable end to close (ETC) torque can be selected within a range of 5000 to 10000 Nm. The maximum ETC torque can reach up to 24000Nm. This spring configuration also features low-pressure operation and allowing for the selection of an appropriate actuator even at 2 bar.

The left and right end covers of the B series big-size pneumatic actuators are equipped with limit screws for convenient adjustment of the travel end limit. The standard travel is 0° ~ 90±5°, and non-standard rotary travels such as 0°~45°, 0°~55°, 0°~75°, and so on are also available.

The installation dimensions of the B series big-size pneumatic actuators comply with international standards. The top mounting dimensions follow the DIN3337 and Namur standards, ensuring direct installation of limit switch box or valve positioners. The bottom installation dimensions adhere to the ISO5211 standard, allowing direct installation with large quarter-turn valves of the same standard.

Structure, Parts and Material

Operating conditions

1. Operating media
Dry or lubricated air, the non-corrosive gases.
2. Air supply pressure
Double acting: 2～8 Bar; Spring return: 2～8 Bar
3. Operating temperature
T0 : Standard: -20℃～+80℃
T1:High temperature: -15℃～+150℃
T2:Low temperature: -35℃～+80℃
T3:Cold temperature: -50℃～+80℃
T4:Cold temperature: -60℃～+80℃
4. Travel adjustment
Have adjustment range of±5°for the rotation at one of the travel end
5. Lubrication
Under normal operating condition, need not accrete lubricant
6. Application
Either indoor or outdoor
7. Highest pressure
The maximum working pressure is 10 bar, but when operating continuously for a long time, the air source pressure is recommended to be less than or equal to 8 bar.

Air Consumption

Weight Table

Sizing information and How to Order

Example:
B-500DAT0
B series double acting actuator 500 size and the the working temperature range is -20℃ ~ 80℃.
B-500SR5T2
B series spring return actuator, 500 size with 5 springs and the working temperature range is from -35℃ ~ 80℃.
Sizing: Double Acting Actuators
The suggested safety factor for double acting actuators under normal working conditions is 20%-30%.
For example, the torque needed by valve is 16300 Nm.Then the torque considered safety factor is 16300*(1+30%)=21190 Nm. The Air Supply is 5 Bar.
According to the output torque table of B series pneumatic actuators with double acting above, we can choose the minimum model is ACHEM B-500DA.

Sizing: Spring Return Actuators
The suggested safety factor for spring return actuator under normal working conditions is 30-50%.
For example, the torque needed by valve is 4500 Nm.Then the torque considered safety factor is 4500*(1+30%)=5850 Nm. The Air Supply is 5 Bar.
According to the output torque table of B series pneumatic actuators with spring return above,
we find output torques of B-500SR7 are：

All the output torque is larger than we needed (5850 Nm). Therefore, the B-500SR7 actuator can meet our requirements and ensure the normal operation of the valve.
Attention1:
This is a simple sizing method. Often, a larger size actuator is chosen, resulting in higher costs. If the four torque values (BTO, ETO, BTC, BTC) of the valve are known, an economical sizing can be achieved, allowing a smaller size actuator to start the valve normally. For the details, please contact with wilson@alpha-achem.com
Attention2:
During the restoration, the spring return actuators' output torque will not be affected by the inputing air from ports of B. On the contrary, it will help in the recovery of the spring.