Boiler-accumulator with steam heating

Contents

Objectives of course work - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Initial data - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

I. Thermal and structural calculations - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

1. Determination of specific thermal productivity - - - - - - - - - - - - - - - -

2. Determination of heat transfer coefficient - - - - - - - - - - - - - - - - - - - - - - - - -

3. Determination of structural dimensions of the apparatus - - - - - - - - - - - - - - - - -

II. Mechanical Calculation of Heat Exchanger Structural Elements

1. Calculation of the apparatus hull - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

2. Calculation of bottoms and covers - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

3. Tube plate thickness calculation - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

4. Calculation of diameter of inlet and outlet branch pipes of heated water - - - - - -

5. Calculation of flanges - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

6. Calculation of the mass of the apparatus - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

7. Calculation of apparatus supports - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

8. Stability calculation - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

III. Calculation of thermal insulation - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

IV. Instrumentation and control instruments - - - - - - - - - - - - - - -

V. Operation and repair - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

VI. Installation information - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

VII. Requirements of Rostekhnadzor - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Bibliographic list - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Graphic part in format A

Specification on Format A

Objectives of coursework

In this course work it is required to perform thermal calculation, mechanical calculation, calculation of thermal insulation of horizontal boiler accumulator, as well as selection of instruments and compliance of heat exchanger with Rostekhnadzor rules. Battery boiler capacity is 6m3. Heating coolant: saturated water steam at excess pressure Rizb. = 0.5 MPa. In the heat exchanger water from 15 to 650C in 6 hours heats up with a pressure of Rabs.=0.6 of MPa.

Source Data:

1. Saturated water vapor temperature: ts = 151.7 ° C (by: ps = 0.5 MPa from Table

physical. water-to-water vapour)

2. Saturated steam pressure: Rabs1 = 0.5MPa

3. Inlet water temperature: t "2 = 15 ° C

4. Outlet water temperature: t "" 2 = 65 ° C

5. Water pressure: Rabs2 = 0.6MPa

6. Time of water heating to initial temperature:

7. Water heater volume: V = 6 m3

Iv. instrumentation and control instruments

The following instrumentation shall be installed in the battery boiler to monitor the heat exchange process:

1) A thermometer and pressure gauge are installed on the steam nozzle to monitor the temperature and pressure of the heating steam..

2) A thermometer is installed in the body of the apparatus to monitor the temperature of the water.

1. Select thermometers.

Thermoelectric thermometers (thermocouples) are used as thermometers.

We choose a chromium-nickel thermometer type TKK:

Calibration characteristic of HC

Measuring range from 200-600С

Average thermoEMF, mV, at 100С

8.3 mV temperature difference

GOST 6616-74

Double vibration-resistant thermoelectric thermometer TKK0515 with movable connector is installed on the steam nozzle.

A double vibration-resistant thermoelectric thermometer TKK0515 with a fixed connector is installed in the housing.

2. Lengthening wires.

The HC wire. Positive life - chromel, color - purple. Negative core - drop, color - yellow. ThermoEMF at t = 100C and t0 = 0C - 6, 9mV.

Grade PCB2.5 mm2

3. Automatic correction of temperature change of free ends is performed using KT-54 compensation box

4. Secondary device.

Millivoltmeter showing type M64.

The scale is selected so that the arrow is in the middle third at the working temperature for steam and the maximum for water.

5. Heating steam pressure measuring device.

We select a reformation pressure vacuum gauge of the MED model 22364 type. The scale is two-sided. To the left of zero, vacuum pressure marks are applied, to the right - excess. It works complete with a secondary automatic differential transformer device of the KPD1 type. GOST 19610-74

Potentiometer of KPP1 type showing with flat scale is used.

6. Automation devices

If necessary, pump shutdown devices can be installed when a certain water level is reached, steam shutdown devices when water is heated to a certain temperature and after a certain amount of time.

V. Operation and repair

Technical management of operation of heat-using plants is carried out by the main power engineer or the main mechanic of the enterprise, direct maintenance of the equipment is carried out by the operational personnel of the workshop. Operation of heat-using plants is carried out according to instructions established by the chief engineer of the enterprise.

The instructions specify the rights, duties and responsibilities of the operating personnel, the procedure for servicing the equipment during normal operation and in case of accidents, the procedure for inspection and repair of the equipment, measures for technical safety and fire prevention equipment.

During the maintenance of the equipment, the personnel must ensure the established mode of operation of heat and mass exchange plants, since each violation of the operating mode entails disruption of the equipment and often leads to an emergency state.

Depending on the nature of the work performed, the workplace of each worker must be equipped and equipped with the necessary devices, devices and tools for performing production operations, as well as devices and protective devices for preventing accidents and possible injuries.

In accordance with sanitary standards, all workplaces must have good lighting and ventilation.

The correct operation of the equipment is ensured by organizing and keeping records on the following indicators:

• steam flow rate for installation;

• quantity of condensate returned;

• quantity of heated heat carrier;

• hourly, shift, daily, monthly and annual water and steam consumption;

• unit specific consumption and steam saving;

Liquid heaters are characterized by such parameters as thermal productivity, maximum temperature of heated water, nominal flow rate of heat carriers, permissible pressure of primary heat carrier. Therefore, the boiler must be equipped with thermometers on the running heating medium pipelines, as well as pressure gauges and flowmeters on the primary coolant pipelines.

On the finished product pipelines and condensate pipelines from the heaters, sampling devices are provided that determine the quality of the condensate. The operation of the plant is monitored using measuring glasses. The liquid level may increase due to looseness, rupture of tubes or clogging of the condensing pot or drain washer, as well as pump malfunction.

It is known that the equipment undergoes wear during operation and loses its initial operability. Minor equipment defects shall be eliminated at the end of the production operation when the equipment is not working. At the same time, inspections of units and parts are carried out to identify their operability and to develop measures for the upcoming repair of equipment.

More complex repairs with replacement of worn-out parts are carried out according to the schedule installed and agreed at the enterprise. At all industrial enterprises, a system of planned preventive repair of equipment is organized, which is a set of organizational and technical measures carried out in a planned manner for the care, supervision, maintenance and repair of equipment.

The PPM system includes three types of repairs: current, medium, overhaul. They are preceded by a period of overhaul, which is performed by personnel in accordance with the instructions. To care for the equipment, the personnel must have the necessary set of tools and accessories, as well as quickly replaceable parts and materials. Overhaul service includes cleaning of heating surfaces, external inspection, detection of defects in operation, serviceability check of safety devices, serviceability of instrumentation and other devices ensuring continuous operation of the equipment.

Ongoing repairs are carried out by personnel. It is used for partial disassembly of units in order to detect the state of parts and eliminate minor faults.

The average repair is carried out at the equipment installation site according to the schedule. The volume is determined by the results of previous inspections. It includes: replacement of worn-out parts, repair of all equipment units. Medium repairs are carried out by specialized teams.

Overhaul is remedial. It is completely disassembled to replace worn parts and other repairs. Major repairs are carried out by specialized construction and installation organizations. If necessary, the installation is delivered to specialized workshops. The scope of major repairs includes all mechanical, electrical, construction and special works.