Components
According to the standard EN ISO 22153:2021 (electric actuators for industrial valves), certain requirements must be set for compliance. An endurance test must be carried out on a model. The standard makes classifications for the duty cycle and corrosion protection
Since we actively supported the standardization process, we are also available to advise you in this regard if anything is unclear.
Important for the practitioner are:
performance
The standard EN ISO 22153:2021 makes classifications for the so-called “duty performance” (duty performance); below the classification is shown without the rarely occurring requirement “Continuous modulating Class D” (permanently modulating). The table refers to part-turn actuators (travel up to 359°).
Rated Torque | 1 – 125 Nm | 126 – 1000 Nm | 1001 – 4000 Nm |
---|---|---|---|
Class A On-Off Cycles per houra | 15 | 10 | 5 |
Class B Inching Starts per hourb | 120 | 60 | 30 |
Class C Modulating Starts per hourc | 1200 | 600 | 300 |
Comments:
- Avoid drives that say Class A from 1000 Nm.
- “Inching” is defined as: “required to occasionally drive the valve to a position between fully open and fully closed.”
- Class C (modulating) increases the requirements to: “required to frequently drive the valve….”
The explanations for the table are as follows in the draft standard:
To a) : One cycle consists of nominal 90Oangular travel in both directions (ie 90O to open and 90O to close), based on an averaged load of at least 30 % of the rated torque with the ability to transmit 100 % of the rated torque for at least 5 % at each end of travel, with a cumulative operating time not exceeding 15 minutes in one hour.
To b) : One start consists of a movement of at least 1O in either direction, with a load of at least 30 % of the rated torque. The cyclic duration factor (ie the ratio between the running period and total period) shall not be less than 25 % (eg 1 sec. running and 3 sec. resting).
To c) : One start consists of a movement of at least 1O in either direction, with a load of at least 30 % of the rated torque.
Endurance
The EN ISO 22153:2021 standard requires a type test that the manufacturer can document himself.
Rated Torque | 1 – 125 Nm | 126 – 1000 Nm | 1001 – 4000 Nm |
---|---|---|---|
Class A + B On-Off Inching Number of cyclesa | 10.000 | 10.000 | 5.000 |
Class C Modulating Number of startsb | 1.800.000 | 1.200.000 | 500.000 |
Comments:
- “Inching” is defined as: “required to occasionally drive the valve to a position between fully open and fully closed. “
- Class C (modulating) increases the requirements to: “required to frequently drive the valve….”
The explanations for the table are as follows in the draft standard:
To a) : One cycle consists of nominal 90Oangular travel in both directions (ie 90O to open and 90O to close), based on an averaged load of at least 30 % of the rated torque with the ability to transmit 100 % of the rated torque for at least 5 % at each end of travel, for angular travel other than 90O the endurance shall be agreed between the purchase and the manufacturer/supplier.
To b) : One start consists of a movement of at least 1O in either direction, with a load of at least 30 % of the rated torque.
Additional requirements: At the end of the test, the drive must still be able to generate at least 90 % of its original torque. The travel of the actuator after the test must be between 98 % and 102 % of the originally set travel.
Corrosion
The following table from the EN ISO 22153:2021 standard provides a classification regarding the required corrosion protection.
The distinction (“low/moderate/high”) may not always be easy for the user. We would be happy to advise you!
TA Roloff drives can also be designed for permanent underwater operation. To do this, click on the “IP 68-Oceangear” button on the product page and find out more about the advantages of hermetic encapsulation. TA 70, TA 130 and TA 140 can also be manufactured with stainless steel housings to meet the highest corrosion protection requirements.
Corrosion category | Exterior | Interior |
---|---|---|
C2 (low) | Atmospheres with low levels of pollution. Mostly rural areas. | Unheated buildings, where condensation may occur, eg depots, sports halls. |
C3 (medium) | Urban and industrial atmospheres, moderate sulfur dioxide pollution. Coastal areas with low salinity. | Production rooms with high humidity and some air pollution, eg food processing plants, laundries, breweries. |
C4 (high) | Industrial areas and coastal areas with moderate salinity. | Chemical plants, swimming pools, coastal shipyards. |
C5 – I (very high industrial) | Industrial areas with high humidity and aggressive atmospheres. | Buildings or areas with almost permanent condensation and with high pollution. |
C5-M (very high marine) | Coastal and offshore areas with high salinity. | Buildings or areas with almost permanent condensation and with high pollution. |
Immersed in water (Im) | Electric actuators covered by this standard are not designed for permanent immersion unless otherwise specified | |
In 1 (Immersed in fresh water) | River installations, hydro-electric power plants | |
Im 2 (Immersed in sea or brackish water) | Harbor areas and offshore structures |