7.2Cooling the STP Pump
There are two methods for cooling: Water cooling and Air cooling.
When sucking gases, cool the STP pump in accordance with the operating pressure range. Also, when performing baking, always cool the STP pump.
Select the best one which fits your vacuum equipment.
7.2.1Water Cooling Method
1)Connect the cooling water pipe to the cooling water port in accordance with Figure 7.1.
2)The female screw PT*1 (RC)1/4 is used in the cooling water port (see Figure 16.1, "External Appearance of the STP Pump").
3)Use connection hose of ID (internal diameter) 8 mm, and secure it to prevent water leakage.
4)Use cooling water under the following conditions:
Amount of water: 2 L/min
Temperature: 5 to 25 ℃
Water pressure: 2.9×105Pa (3kgf/cm2) or lower
NOTICE
◇Use clean water as much as possible.
Cooling water containing foreign materials may corrode or clog the cooling water pipe.
When the cooling system is clogged with foreign materials, clogs may possibly be removed by feeding cooling water reversely.
◇When the STP pump is overheated due to shortage or suspension of water, the protective function detects the overheated condition in the STP pump and stops the STP pump.
As a further safety procedure, attach a flow switch to the cooling water exit so that the STP pump stops if abnormal cooling water flow occurs (a flow switch is available on the market).
◇When the STP pump is not to be used for a long period of time or it is to be moved after use, introduce compressed air from one side of the inlet/outlet port so that no water will remain inside.
◇The joint for water cooling unit is made of brass. To prevent corrosion, connect the brass joint.
*1: JIS
