| 1.1 |
The basic unit comprises of a 90°, 180° or 360° worm box. The high ratio reduction ensures back driving from the valve cannot occur and gives low input torque for high output torque. Input drive can be handwheel or electric/hydraulic/pneumatic actuator. | |
| 1.2 | Reduction spur boxes can be added to the input face to increase the ratio. This is a standard feature on the larger units. The spur boxes can be single, double, triple or quadruple reduction. | |
| 1.3 | Ancillary
items are often supplied to customer requirements. Common features are:
| |
| Refer to the Mastergear catalogue for details. |
| 2.1 | At any time when maintenance is carried out | |
| 2.2 |
Actuators should not be overloaded by placing
extension bars in handwheels. On electric, hydraulic or pneumatic drives it is bad practice to drive in an overload condition | |
| 2.3 | The valve maker should consider the necessity for fitting a pressure relief valve to relieve pressure in the event of a valve stem seal failure. This can be fitted either in the valve, adaptor flange or the indicator cap of the MASTERGEAR actuator. | |
| 2.4 | Setting of the actuator stop screw is the responsibility of the valve manufacturer. Once set, these should not be tampered with on site. | |
| 2.5 | Isolate any electric wiring to limit switches or electric actuators before carrying out any maintenance work (If fitted). Ensure that power cannot be accidentally applied. This also applies to any hydraulic/pneumatic power lines. | |
| 2.6 | Where eyebolts are fitted to actuators, they are to be used for lifting the MASTERGEAR actuator only. |
| 3.1 | Actuators must be stored in a clean, dry warehouse and protected from variations in temperature, high humidity and dust. Storage temperature range should be between 0°C to 50°C. | |
| 3.2 | Units should be stored so as to avoid accidental damage. | |
| 3.3 | At 3 monthly intervals, operate the actuator for >one complete open/shut cycle either by handwheel or power device. | |
| 3.4 | Inspect any unpainted surfaces for rust at 3 monthly intervals. Apply a preservative oil coating if required. | |
| 3.5 |
Maintain records of storage/inspection for the above MASTERGEAR reserves the right to inspect records and units when required. | |
| 3.6 | If the actuator has been operated every 3 months (see item 4.3) it should be returned to the factory for inspection and refurbishment after 10 years. If it has not been operated during storage, it should be returned after 5 years. |
| 5.1 |
Mastergear actuators are normally supplied with a red oxide primer finish for the customer to apply finish paint coating. It is the customer’s responsibility to sufficiently mask off any sensitive areas prior to any painting or shot-blasting and painting work. | |
Attention is
drawn to the following sensitive areas:
| ||
| 5.2 | After final painting, clean and apply a small amount of grease around the top quadrant journal as this can wash out with cleaning solvents on the painting process. Failure to pay attention to this detail may result in premature corrosion at this point. |
| 7.1 |
The units require very little maintenance if all storage and installation procedures have been followed. It is good practice at six monthly intervals to add a small amount of grease around the top quadrant journal (ref. Painting Section 6.2) and also around the input shaft on handwheel drives. If the valve is normally idle, operate one full open/shut cycle every three months. Should any major maintenance or strip down work be required, we recommend that the unit should be returned to our factory. |
| 8.1 |
If spare parts or information are required, please state the model size, serial number and quantity of units. The model size and serial number are available on the nameplate fitted to the worm box cover. |