API St 611:2008(2019) pdf download

API St 611:2008(2019) pdf download.General-purpose Steam Turbines for Petroleum, Chemical, and Gas Industry Services.
6.10.4.2 S.als and Deftectors
6.10.4.2.1 Bearing housmgs shall be equipped with replaceable labyrinth-style end seals and deflectors where the shaft passes through the housing: lip-type seals shall not be used. The seals and deflectors shall be made of non- sparking materials, The design of the seals and deflectors shall effectively retain oil in the housing and prevent entry of steam, condensation and foreign material into the housing
. 6.10.4.2.2 If specthed, bearing isolation seals providing a positive tight seal to prevent the ingress of atmospheric contaminants slid be supplied.
6.10.4.3 OIl Mist Lubrication
6.10.4,3.1 An NPS 1j4 oil mist inlet connection snaIl be provided in the top half of the bearing houswg. The pure- or purge oil mist fitting connections shall be located so that oil mist will flow through rolling element bearings. On pure. mist systems, there shall be no internal passages to short circuit oil mist from inlet to vent.
6.10.4.3.2 A threaded 6 mm (NPS 114) vent connection shall be provided on the housing or end cover for each of the spaces between the rolling element bearings and the housing shaft closures. Alternatively. where oil mist connections are between each housing shaft closure and the bearings, one vent central to the housing shall be Supplied. Housrngs with only sleeve type bearings shall have the vent located near the end of the houswrg.
6.10.4.3.3 Shielded or sealed bearings shall not be used.
6.10.4.3.4 If pure oil mist lubrication Is specified. oil rings or flingers (If any) and constant level oilers shall not be provided, and a mark Indicating the oil level Is not required. If purge of mist lubncalion Is specified, these items shall be provided and the oiler thai be piped so that it is maintained at the internal pressure of the bearing housing.
At process operating temperatures above 300 C (570 F), bearing housings with pure-oil mist lubrication may require special features to reduce heating of the bearing races by heat transfer, Typical features are:
a) heat Sink type fingers;
b) stainless steel shafts having low thermal conductivity;
C) thermal barriers;
d) fan cooling; and
e) purge oil mist lubrication (in place of pure oil mist) with oil (sump) cooling.
6.10.4.3.5 The oil mist supply and drain fittings shall be provided by the purchaser.
6.10.4,4 Vibration Measurement
6.10.4.4.1 Al bearing housings thai have dimpled locations ii the vertical (V), horizontal (H) at each bearing housing and location (A) at the outboard bearing housing as shown in Figure 1 and in accordance with 8.3.3lg to facilitate consistent vibration measurements, The dimples shall be suitable for accurate location of a hand-held vibration transducer with an extension ‘wand. Dimples may be cast or mactimed and shall be nominally 2 mm (0.080 wi.) deep with an included angle of 120 as shown in Figure 2. The dimple shall be located as close to the bearing oente.lwie as practical for the vertical CV) and horizontal (H) locations only..
. 6.10.4.4.2 If specified, a flat surface of an agreed size and location shall be provided for mounting of magnetic- based seismic vibration measuring equipment
6.10.4.4.6 Oil connections on beanng housrngs shall be in accordance with 6.10.41.3.
6.10.4.4.7 Axially split bearing housings shall have a metal-to-metal joint with cylindrical locating dowels.
6.11 Lubrication
6.11.1 Unless otherwise specified, bearings and bearing housings shall be arranged for oil lubrication using a mineral oil in accordance with ISO 8068.
. 6.11.2 If specified or required by the turbine, a pressurized od system shall be furnished to supply oil at a suitable pressure or pressures, as applicable, to the:
. a) the bearings of the drrver and of the driven equipment (induding any gear): and b) any governor and control-oil system.
6.11.3 Unless otherwise specified, pressurized oil systems shall conform to the requirements of ISO 10438-3. API 614 Chapter 3 (see Annex D. Figure 0.1 and Table D.1 for a schematic and the various options applicable).
6.11.4 Where oil is supplied from a common system to two or more components of a machinery train (such as a compressor, a gear, and a turbine), the vendor having unit responsibility shall ensure compatibility of type, grade, pressure and temperature of oil for all equipment served by the common system.