Running Turbine

Running

1. When the governing system assumes control, then adjust the speed fully open the emergency stop valve setting until the required speed, watching the turbinr speed following.
2. Put into service the load as required.
3. Make sure that bearing temperature is under 80C. When over 85 C, stop the turbine.
4. Check the bearing oil pressure gauge to see that the bearing oil pressure is 0.7 - 1.5 kg/cm2 G.
5. Adjust the supply of cooling water to the oil cooler to maintain oil temperature at outlet 30 - 50 C.
6. Watch the turbine for unusual sounds and vibrations and take proper action if should occur.

Lubrication And Governing System ENV-116G Turbine 2

6. Over Speed Trip

The turbine is aquipped with an overspeed trip which prevents overspeed of the turbine by tripping the emergency stop valve and shutting off the supply of the steam to the turbine.

If the turbine speed increases by abnormal condition as much as predetermined value (about 115% rated speed), the over-speed operates and shuts the emergency stop valve through the emergency mechanism linkage.

It is an eccentric weight type and is equipped in the main oil pump end of the gear shaft.

The center of the gravity of the weight is slightly offset from the axis of ratation and is normally held in place by the compression of the spring.

When the turbine is operating at normal speed, the lever is kept in its normal position.

But when the turbine reaches the predetermined speed (about 115% rated speed), the eccentric weight due to centrifugal force, overcomes the spring compression and moves outward, and strikes the lever. The valve moves down-ward, supply oil to trip cylinder is cut off and be drained.

Supply oil press., from overspeed trip decreases, The oil piston moves up-watd and it rotates the trip lever through the trip pin.

The latch pin and spring seat hand wheel, spindle, coupling, pilot disc and disc are moved together by the spring.

Consequently, the emergency stop valve is shut down.

The tripping speed is tested at the factory and should not be changed unless absoulutely necessary.

When needed, loose sets screw then turn the adjust screw clocwise to increase the set speed or counter clockwise to decrease the set speed.

If should be taken that to lock the set screw after adjusting of the overspeed trip.

If the overspeed trip has been operated, pull the red reset knop before the emrgency stop valve is reset.

When manual trip is needed, push the trip knob the emergency stop valve is tripped.

7. Excess Back Pressure Trip

The turbine is provided with an excess pressure trip device to prevent trouble due to excessive back pressure rise.

When the turbine back pressure rises, the steam sentinel valve begins to emit steam.

When it rises further up the operating pressure, the pressure switch acts and actuates the solenoid valve provided in the hydraulic circuit led to trip cylinder of emergency stop valve, due to which oil pressure is shut off and discharged to drain.

Therefore, in the same manner as when the overspeed trip device acts, the trip mechanism of emergency stop valve, closes the emergency stop valve to shut off steam inflow.

The operating pressure of the excess back pressure trip device can be adjusted as required by turning the adjust screw of pressure switch.

Lubrication and Governing System ENV-116G Turbine 1

1. General

• The lube oil system for turbine and reduction gear. Lube oil is sucked up from the oil reservoir by the main oil pump or aux. Oil pump and supplied to the pinion bearing, gear bearing and gear teeth surface through the stariner and oil cooler, and the it returns to the oil reservoir.
• The bearing oil pressure is regulated by oil relief valve, and excess oil returns to the oil reservoir.

2.  Speed Governor

• The rotational speed of this turbine is controlled by the Wood Ward governor.
• This governor is driven by the drive gearounted on the front end of the main oil shaft.
• It ensures an exellent speed controlling, enabling to keep always constant the rotational speed of the turbine regardless  of variation of load and steam conditions.
• The speed setting point can be significantly changed by turning the speed setting dial with hand the remote control motor.

3. Main Oil Pump and Governor Drive Gear

• The main oil pump is driven at properly reduced or increased speed by the drive gear (drive) mounted on the upper end of the gear shaft and the drive gear (follow) fitted to the gear (drive).
• A governor driving gear (drive) is mounted on one end of the pump gear.
• This gear drives the governor through the gear (follow).
• A tachometer transmitter is provided at the upper end of the pump gear (follow).

4. Auxiliary Oil Pump

• This turbine equipped with auxiliary oil to furnish bearing lubrication during starting and shut down periods.
• The until has one motor-operated pump which providess auto-start and stop by means of a pressure switch.

5. Oil Relief Valve

• The oil relief valves is mounted on the bed plate. Usually, it serves to keep constant the bearing oil pressure and gear spray oil pressure.
• The optimum oil pressure during operation is 0.7 ~ 1.5 kg/cm2 G.
• The oil pressure is regulated by the compression force of the spring.
• It is recommended to set it to obtain 1.5kg/cm2 G at the optimum oil temperature (30~50^0 C at cooler outlet) with the turbine's specified rotational speed.

To be Continued: 
Lubrication and Governing System ENV-116G Turbine 12

Reduction Gear Turbine for Cargo Oil Pump ENV-116G

Type ENV-116G Turbine for Cargo Oil Pump, Reduction Gear

1. General

• This reduction gear is designed high reduction ratio and the pinion shaft end fits a turbine rotor in order to obtain high efficiency and economy of space.

2. Gear Casing

• These are made of close-grained cast iron and divided in the vertical plane through the axis of the pinion and wheel.
• The rear casing of the turbine is bolted on the rear gear casing. The rear gear casing is mounted on the bedplate and lub. Oil drains out to the bedplate.

3. Gear Wheel and Pinion

• The pinion is made from Ni-Cr-Mo steel, and the gear wheel is made from forged steel, and these are carefully heat-treated.
• The gear wheel is pressed on the gear shaft and secured with keys. The one end of the wheel shaft is connected with the load by the coupling through intermediate shaft and another end drives a oil pump and a tachometer through a drive gear.
• The gear and pinion teeth are of the involute single herical type and precisely machined.
• The pinion end thrust bearing of michell type supports against the thrust force.

4. Bearing

• The pinion and gear journal bearings is steel back lined with white metal and split in the vertical plane of the centerline to from bearing halves.
• The pinion bearings and two gear bearings is fitted gear casing rearby bearing cover with bolts firmly.
• The luch of bearing prevents to rotate and remove toward axis. Lubricating oil for bearings is supplied through the hole of the gear casing rear.
• Thrust force of pinion is supported by michell type, and the gear wheel position is by plen thrust bearing and liners.

Construction of ENV-116G Turbine 2

6. Emergency Stop and Governor Valve

The emergency stop valve is situated upper position and the governor valve is situated down position.

1. Emergency Stop Valve

• The emergency stop valve has two distinct purposes. First, to control throttling of steam when starting and bring the turbine up to speed; second, to act as quick-closing valve when tripped by hand or remote=trip, and as emergency stop valve when tripped automatically by safety device such as over speed trip, back pressure trip, low oil pressure trip.
• The spindle and the spring seat is threaded, the spring is compressed by the spring seat, and the pin on the spring seat is set by lever which is connected to the trip cylinder.
• The trip cylinder consist of the piston rod, the piston, the spring and the cylinder body. When the oil pressure in the cylinder body decrease, the piston is moved upward by the spring force together with the piston rod and the lever. At same time the pin on the spring seat is severed from the lever, so the spring seat, the spindle, the pilot disc and the disc are forced down by the spring.
• Thus, the emergency stop valve, the piston is situated at reset position by the oil pressure in thecylinder body. By hand the hand wheel is turned to the right, and by turning th hand wheel to the left is opened the emergency stop valve.
• The disc must be open after the pilot disc and being small deference pressure on the disc upper and lower face, by means of restricting the steam flow with the adjusting disc.

2. Governor Valve

• The Governor valve position is determined by movement of the governor and the governor valve controls the flow of steam to the steam chest.
• The governor valve consist of the adjusting disc, the disc guide and the stem, and is the balance type. The adjusting disc is guided by the bush and is controlled by the stem on account of the governor movement. The stem flows inter the steam chest through the port on the diec guide.

3. Governor Link

• The governing shaft of the governor and the governor valve stem are connected with the governor link. and that is consisted of ball joints, a lever, rods and fulcrum pins. The link conveys smoothly the movement of the governor to the governor valve.
• The link needs the adjustment for reassembly that the clearance between the governor valve stem and the stopper of the valve seat is about 2mm when the governor is full shutting. Changing the position of the pin needs in case the steam flow of the governor valve is reduced at full opening of the governor.

Construction of ENV-116G Turbine 1

 Construction of ENV-116G Turbine

1. Turbine Casing

• The turbine casing consist of a casing rear, and a casing front bolted together at the vertical joint
• When removing the casing front it must be lifted horizontally enough to clear the rotor blades in order to prevent the possibility of damage to the blades.

2. Turbine Blades

• Blades is so important part for turbine at point of high efficiency and reliability that designing and construction are paid very careful attention, that especially sectional shape of blade is manufacturedd with skillful engineering of long experiment and development at our shop.
• The turbine blading consist of one row of stationary blade, and two row of rotating blades which are made of 12% Cr. Stainless Steel, the surface is finished elaborately.
• The rotating blades are mounted on rotor with T-root, and their tops are cramped each other with several shrouds.
• The stationary blades are mounted on retainer with dovetail.

3. Turbine Rotor

• The rotor disc is shrunk and keyed on the pinion shaft which overhung from two pinion bearings.
• The disc is careful heat treated Ni-Cr Steel. After the blades are installed, the entire rotating assembly is dynamically.

4. Nozzle and Stationary Blade Retainer

• The nozzle made of 13% Cr. Stainless Steel rings, is distributed to all circumference of the roror in order to get large power. And its all surface, especially steam path is finished elaborately with reamer drill.
• The nozzle ring is bolted up the steam chest firmly.
• The stationary blade retainer is fitted to casing by sliding. And its all surface, especially steam path is finished elaborately with reamer drill.
• The nozzle ring is bolted up the steam chest firmly.

5. Turbine Gland

• The turbine casing opening around the shaft are sealed by means of carbon ring glands.
• The gland seals the shaft opening againts leakage of steam to atmosphere in non-condensing unit, or leakage of air into the turbine in condensing units.
• Three carbon rings are holded between gland diapragm, and one ring is made up of three segments held together aroundthe shaft by a garter spring.
• The segment are made of carbon material consolidated with a suitable bind and accurately machined to size.
• The quality of these rings is held to a special specification by the exercise of most rigid inspection.
• The garter springs are made of 18 - 8 Cr-Ni stainless steel wire and this wire is insured longer life forthese springs than could otherwise be expected.
• The pinion shaft which is in contact with the carbon rings is protected hard chrome plating, and it keeps resist from wear and corrosion.
• Non condensing service, the leakage steam through two carbon rings is led to leakage steam condenser or atmosphere.
• Therefore, the last carbon ring seals steam leakage to atmosphere. Condensing service sealing steam which is injected to the gland between firts carbon ring and second carbon ring, prevent the air leakage into the turbine casing.
• The leakage steam is led to the leakage steam condenser or atmosphere.
• The leakage steam piping be paid the attention that the steam have no pressure.
• The suitable sealing steam source pressure is 0.2kg/cm2 G - 0.4 kg/cm2 G.
• If gland leakage has been observed the rings should be refutted by carefully grinding the ends of the reduce the clearance.
• This should be carefully done taking not more than about 0.025 mm at a time off each face. ( 0.025 off each end of each segment will reduce the ring diameter roughly 0.05 mm)
• If spare gland rings are in stock they will be dimensioned to have the standard clearances show in the illustration.
• If these spare are installed in a unit operating at relatively high temperature, it is advisable to start up the unit very cautiously the firts time, making sure that the glands function properly and show no signs of being tight. 
• The gland ring is formed beveled section.

GENERAL DESCRIPTION OF ENV-116

GENERAL DESCRIPTION OF ENV-116 

   The " ENV-116 GEARED TURBINE" in this instruction book is designed very compact, ligh weight and high efficiency and manufactured with long experiments of our shop.

   This turbine answers all requirements of study and dependable mechanical drive unit offers the combination of fundamental simplicity with utmost refinement of design and workmanship.

  It is built for long service with sustained efficiency and dependable performance.

   It should be remembered, hoeever, that though simple in design and requiring a minimum of attention in operation, the turbine is like any other piece of high class machinery in that this minimum of attention must be given at regular intervals if the expected satisfactory are essetial to trouble-free operation.

  The primary purpose of this instruction book is to assist the operator in understanding the construction of unit, the purpose of the several part, and to offer, such suggestion for proper operation and maintenance as will, if followed, insure long and satisfactory service.

  Type "ENV" Turbine has following special characters.

  1. Type Turbine

It is of the simple impulse type, consisting of one velocity-compounded stage with two rows of rotating blades and one row of stationary blades. This rotor is mounted on pinion shaft end of reduction gear, therefore the turbine is most simplicity and compact.

High speed and suitable nozzles for the stem conditions fitted on all circumference of rotor realize high efficiency and large power for small simple impulse turbine.

  2. Trip System

When the turbine is stopped by safety device ( over speed trip, low oil press trip, or excess beck press. trip) the emergency stop and governor valve shut the steam flow immediately and it protect the turbine safety.
  3. Simple Maintanance

This turbine is so simple construction that need much times of replacement or repair than other ordinary turbine.

Type ENV-116G Turbine for Cargo Oil Pump

Type ENV-116G Turbine for Cargo Oil Pump working Instruction

Special Information and expected performance curve

1	Type	Mitsubishi ENV-116G, vertical single stage impulse steam turbine with single reduction gear
2	No. of supply	4 set (for 1 ship)
3	Machine No.	T06358 ~ T06361
4	Output ( Continuous Rating)	750 kW
5	Steam Condition: Inlet Steam Pressure Inlet Steam Temperature Exhaust Vacuum	14.5 kg/cm2G Sat. 550 mmHg
6	No. of Revolutio Turbine Gear	9494 RPM 1610 RPM
7	Reduction Gear Type Gear Size (Center Distance and Widht) Gear Ratio	46 x 15 cm 5.897
8	Steam Inlet Flange	JIS 20K – 100 mm dia.
9	Exhaust Flange	JIS 5K – 300 mm dia.
10	Rotating Direction on Gear Shaft ( Viewed from Governor Side)	CCW
11	Governor Type Speed Range	PSG 103 ~ 50 %
12	Lubrication System Lubricant Oil Reservoir Capacity Main Oil Pump Capacity Auziliary Oil Pump Capacity Oil Cooler Type Cooling Surface Area Required Cooling Water Cooling Water Inlet and Outlet Flage	Forced Turbine oil #140 ~ #180 270 lt 5.9 m3/h x 3 kg/cm2 G (Shaft driven) 6.5 m3/h x 1 kg/cm2 G Motor driven 0.4 kW x 3450 rpm) Shell and tube 5 m2 8 m3/h x Max. 32 * C x Max. 5 kg/cm2 G x Sea Water JIS 5K – 32 mm dia.
13	Safety Device (1) Mechanical Over Speed Trip (2) Electrical Over Speed Trip Alarm (3) Lub. Oil Pressure Trip (4) back Pressure Trip (5) Sentinel Valve (6) Remote Trip (7) Manual Trip (8) Pump Bearing Temperature Trip (9) Pump Casing Overheat Trip (10) BHD Gland High Trip	< Setting> 10918 rpm (tol. 285) 10443 rpm (tol. 95) 0.5 kg/cm2 G (tol. 0,1) 1.5 kg/cm2 G (tol. 0.2) 1.0 kg/cm2 G (tol. 0.2)
	Note: Sensers for alarm or trip ( marked at safety device) shall be provided by pump manufactured or shipbuilder.
14	Steam Consumption When of specified conditions are supplied, steam consumption shal be as follows.
	Output Steam Condition Steam Consumption Exhaust Enthalpy	750 kW 14.5 x Sat. x 550 mmHg 8020 kg/h 583.4 kcal/kg
	Note: The above figure are guaranteed with 3% tolerances for uncoidable error of measuring instrument and workmanship.