توضیحات

Introduction

A steel hot-water boiler is a device that heats water to a temperature below the boiling point by burning fuels such as gas, diesel, or fuel oil, or by using electrical energy. It is used to provide heating for buildings, greenhouses, swimming pools, and various industrial applications. These boilers are typically installed in mechanical rooms and are made of durable steel plates.

Technical Specifications

1) Heating Capacity

• Measured in kcal/h or kW
• Typical range: 50,000 kcal/h to 3,000,000 kcal/h

2) Working Pressure

• Standard pressure: 2 to 6 bar
• In industrial or high-temperature hot-water models, the pressure may reach up to 12 bar

3) Operating Temperature

• Normal operating temperature: 90°C – 110°C
• Design temperature: 110°C to 150°C for safety margin

4) Thermal Design Type

• Two Pass,Three Pass, Wet Back, or Dry Back
• Wet Back models include a water-cooled reversing chamber, offering higher efficiency and reduced maintenance

5) Material of Shell and Tubes

• Shell, Made of fire-tube boiler steel plates such as DIN 17155 or DIN 17170
•  Plate thickness: 6 to 12 mm
• Tubes,  Seamless fire-tube steel pipes, grades ST35.8 / ST37.8

6) Dimensions & Weight

• Height, diameter, and length depend on boiler capacity
• Weight varies from 800 kg up to more than 5,000 kg

7) Fuel Type and Burner Options

• Natural gas burner
• Diesel burner
• Dual-fuel burner (gas + diesel)
• Heavy fuel oil burner (industrial applications)

8) Efficiency

• Typical efficiency: 85% to 92%
• Higher efficiency is achieved in three-pass designs and optimized combustion flow dynamics

9) Inlet/Outlet Connections

•  Cold-water inlet diameter: 2″ to 6″
• Hot-water outlet diameter: 2″ to 6″

10) Control & Safety System

Includes:

• Main thermostat
• High-limit thermostat
• Pressure gauge (manometer)
• Temperature gauge (thermometer)
•  Safety valve
•  Burner control unit
•  Pressure control switch
•  Drain valve
• Air vent valve

11) Insulation

• Rock wool insulation, 50 to 100 mm thickness
• Outer cladding made of galvanized steel, stainless steel, or aluminum sheets

12) Standards and Certifications

The boiler must comply with:

• Iran National Standard ISIRI 4231
• Hydrostatic pressure test certification
• Welding tests: RT (Radiographic Test) or UT (Ultrasonic Test)
• CE certification for export