0 Preface With the continuous improvement of social life, people put forward higher requirements for their work and living environment. Comfort, health, energy saving, pollution-free become a new generation of air-conditioning system to pursue the goal. Along the trend, the company successfully developed a soil heat pump unit for radiant panel systems. 1 For radiant panel systems Soil heat pump units Introduction Soil heat pump units for radiant panel systems have their own unique features and controls. First of all, the new wind turbine system with heat pump function is added. The new fan not only for users perennial delivery of fresh air of appropriate temperature, but also bear the indoor air dehumidification load, to prevent condensation of the radiant panel, in winter to add a fresh air preheating function. Furthermore, the control embodies the concept of people-oriented: safe, convenient and flexible. System structure See the working principle of soil heat pump unit (Figure 1). The electric control system of the soil heat pump unit is more complex, the host and the new fan are independent two sets of refrigeration systems, which are closely linked through the indoor key parameter of dew point temperature to coordinate the work so as to create a comfortable and healthy Living space. 2 soil heat pump electrical control system design 2.1 Soil heat pump electrical control design overview Soil heat pump machine cooling, heating, ventilation three working modes. Cooling mode: start the unit, start the new fan and work in the dehumidification mode, this time, the fan speed operation, the new air valve is closed, the indoor air bypass valve open, the exhaust fan does not work, indoor air circulation dehumidification, and gradually reduce the indoor Air dew point temperature. After 30 minutes, indoor dew point temperature, if the dew point temperature drops to the set point tdew1, send a signal to the host, the host starts cooling, chilled water to the radiator. Host water temperature setting will change with indoor dew point temperature for dynamic adjustment. When the dew point temperature drops to the set point tdew2, the fresh air valve opens, the exhaust fan starts, the blower runs at a low speed, and the fresh air is delivered to the user. Heating mode: the new fan and the host at the same time start. The new air valve opens, the blower operates at low speed and delivers fresh air to the interior. In the heating mode, the fresh air can be preheated function, the humidification equipment is installed on the air supply side to detect the relative humidity in the room. When it is detected that the indoor air is dry and does not meet the design requirements, the air humidifies the air supply. The main compressor starts, delivering suitable hot water to the radiant panel. Ventilation mode: The fresh air valve is opened, the bypass valve for indoor air return is closed, the air blower and exhaust fan operate at high speed, and the fresh air is delivered to the user. 2.2 soil heat pump power control design points 2.2.1 dew point temperature acquisition: dew point temperature is a key parameter of soil heat pump system, the design uses the indoor relative humidity and dry bulb temperature of two parameters, the use of control board microcontroller set Look-up procedures, indirect detection of the corresponding air conditioning area dew point temperature. According to the value of indoor dew point temperature control of the working status of the new fan and the host start and stop, and require tdew1, tdew2, Δt1, Δt2 adjustable parameters. See Figure 2 Figure 1 The working principle of the unit 1, the new air valve 2, the return air bypass valve 3, the heat recovery 4, the exhaust fan 5, the blower 6, the fin heat exchanger 7, the four-way valve 8, the compressor 9, gas-liquid separator 10, outdoor side heat exchanger 11, two-way filter 12, two-way thermal expansion valve 13, expansion tank 14, indoor water pump 15, outdoor water pump Figure 2 dew point temperature setting diagram 2.2.2 cooling plate supply Temperature settings: In order to improve the host operating efficiency, to avoid the frequent start of the host, the host water temperature (delivered to the radiator) set point, within a certain range of requirements with indoor dew point temperature changes for dynamic adjustment. Dew point temperature dropped, the host of the water temperature set value also decreases, increasing the radiating plate cooling capacity. 2.2.3 fan automatic gear shift: blower, exhaust fan should be based on different operating modes of the unit, automatic shift. In meeting the system performance requirements under the premise of the fan can run at low speed, and strive to reduce system noise and noise. 2.2.4 The indoor temperature setting takes precedence over the host water temperature setting to control the soil heat pump unit start and stop. That is when the indoor temperature reaches the user's set requirements, you can control the host compressor or all of the inputs, quit running. 2.2.5 Host adopts dual-head or multi-head combination (except for the capacity of small units, cooling capacity ≤ 10kW), energy classification can be adjusted. 2.2.6 Auxiliary heating function: The fresh air preheating function in heating mode: When the fresh air temperature drops to the set value in the cold season, start the fresh air preheater to prevent the frost in the heat exchanger's channel. Fresh air preheater PTC ceramic material. This kind of ceramic heating element has small thermal resistance and high heat exchange efficiency. Its most prominent advantage lies in the safety performance of its work. That is, the PTC heater can not sufficiently dissipate heat due to fan failure. The power will drop sharply, at this time the surface temperature of the heater is maintained at a Curie temperature of about 250 ° C., and there is no danger of burning. 2.2.7 The system can be configured remote telephone control, open off, off units, pre-cooling (hot) room. 2.2.8 Various safety assurance measures necessary for system operation: Exhaust pressure protection of compressor, suction pressure protection, overload protection, antifreeze protection, various temperature protection of new fan circuit, and three kinds of operation modes Interlocking and so on. 2.3 Hardware Components (See Figure 3) Figure 3 Schematic Diagram of Hardware PIC16F874 microcontroller is the core components of the soil heat pump unit control board, which is the United States Microchip company's products, with 8 10-bit A / D converter, an internal 4K FLASH memory, 256 * 8 EEPROM memory, five multi-function ports, three timer / WDT, the microcontroller rich configuration, fully meet the needs of air-conditioning controller. Control board uses the same type of two single-chip, a dedicated microcontroller dew-point temperature acquisition, display and dew point temperature, the control signal output. Another piece of microcontroller for the new fan and host control. The main control board in the circuit design, component selection, printed circuit board design, wiring and manufacturing processes have considered the system's electromagnetic compatibility. The main measures include: grounding, filtering, isolation. Printed circuit boards include: rational partition board, the distinction between digital mode, reasonable wiring, shop, in order to reduce interference. 2.3.1 Control board input and output Six analog inputs: four NTC thermistor, two for the host for the return water temperature detection, two for the fresh air system to send, return air temperature detection. Two 4-20mA standard signal input for temperature and humidity input. Switch input: including various safety protection units, off-site boot. Keyboard input: including switch unit, operation mode selection, parameter setting and so on. Relay Output: Drive load includes: compressor, pump, fan, auxiliary heater, control signal and so on. 2.3.2 Power Circuit The system uses dual independent power supply circuit, respectively, the number of die power supply. Including AC adapter (220V / 12V), bridge rectifier circuit, filter capacitor, integrated power supply LM7812CT, MC7805T composition, for the control board to provide +12 V, +5 V DC voltage. 2.3.3 temperature acquisition circuit PIC16F874 own A / D converter circuit, the temperature signal is collected directly, simplifying the peripheral circuits. In this system we use four temperature signals. Two for the host for the return temperature of the collection. Two for the new fan to send, return air temperature acquisition. Four temperature can be displayed on the unit control panel. This unit in the commissioning operation, through the supply, backwater (wind) temperature, can directly determine the system running status. 2.3.4 Relative Humidity and Dry-bulb Temperature Acquisition Circuit The two 4-20mA temperature and humidity standard signals collected at the site will be converted to millivolt signal by standard resistance and sent to the singlechip. Dew point corresponding to this temperature, the output is displayed. In the analog data acquisition, in order to prevent interference, the program uses a digital filtering technology - average filtering. The average filter has a good inhibitory effect on the periodic interference. 2.3.5 LED display circuit LED display circuit uses a dynamic scan display. Although the dynamic scanning takes up more time for some MPUs, it uses less hardware and saves board space. The system uses three sets of three LED display circuit, a group for the display of soil heat pump supply and return water temperature and the operating status of the unit; a group used to display the fresh air system, air supply, return air temperature and the operating status of the unit; One group is used to show the dew point temperature. LED common anode seven sections of digital control, driven by the SCM dynamic scan mode, each scan time of 3ms, the application uses the loop on the PORTD port continuously output data, and conversion, display. Cycle time is less than 20ms, the LED display data, people will not feel flashing phenomenon. 2.3.6 Binary input and key input circuit Binary input includes activation of each fault point (that is, normally closed contact is disconnected) and remote control signal input. Key input, including unit on, off, mode selection, parameter adjustment. Digital input, the key input MCU chip used to borrow the LED bit select pin. The use of scanning cycle detection, thus greatly reducing the hardware resources. An additional delay timer is added when the key is pressed. As an anti-shake operation, the on / off and mode keys increase the delay of 1s to prevent misoperation. The switch signal input has also been anti-jamming processing, continuous reading of the signal twice in order to confirm the fault signal. 2.3.7 Relay drive circuit Drive circuit using ULN2003 reverse drive module, the driver is a collector open circuit seven non-gate circuit, with Darlington output, strong drive capability. 2.4 Software Features The main functions of the software are: system initialization, self-test program, data acquisition and A / D conversion, look-up program, boot program, shutdown program, run mode judgment program, key scan program, fault scan program, Program, temperature judging program, trouble shooting program, load driver, delay program and the like. 3 Setting of each parameter in the actual application Main parameter setting table of unit Parameter description Default Unit tdew1 Dew point temperature 1 point
Blind Flange /Tube Sheet
Standard:
ANSI B16.5,ANSI B16.47,ANSI B16.48, ANSI B16.36, MSS SP-44
EN1092-1 BS 4054 clients 'dwg
AWWA C207 Class D Ring
AWWA C207 Class D Blind
AWWA C207 Class D Hub
AWWA C207 Class E Ring
AWWA C207 Class E Blind
AWWA C207 Class E Hub
Size: 1/2''~60''
Class Rating: 150~2500
Facing: RF(raised face);FF(flat face);RTJ(ring type joint);RJ(ring joint face)
TG(tongue and groove face);MFM(male and female face)
Manufacturing process: forge,
Material:
Carbon steel:
ASTM A105;
ASTM A266 GR.1,GR.2,GR.3,GR.4
Stainless steel:
304/SUS304/UNS S30400/1.4301
304L/UNS S30403/1.4306;
304H/UNS S30409/1.4948;
309S/UNS S30908/1.4833
309H/UNS S30909;
310S/UNS S31008/1.4845;
310H/UNS S31009;
316/UNS S31600/1.4401;
316Ti/UNS S31635/1.4571;
316H/UNS S31609/1.4436;
316L/UNS S31603/1.4404;
316LN/UNS S31653;
317/UNS S31700;
317L/UNS S31703/1.4438;
321/UNS S32100/1.4541;
321H/UNS S32109;
347/UNS S34700/1.4550;
347H/UNS S34709/1.4912;
348/UNS S34800;
Alloy steel:
ASTM A694 F42/F46/F48/F50/F52/F56/F60/F65/F70;
ASTM A182 F5a/F5/F9/F11/F12/F22/F91;
ASTM A350 LF1/LF2/LF3;
Duplex steel:
ASTM A182 F51/S31803/1.4462;
ASTM A182 F53/S2507/S32750/1.4401;
ASTM A182 F55/S32760/1.4501/Zeron 100;
2205/F60/S32205;
ASTM A182 F44/S31254/254SMO/1.4547;
17-4PH/S17400/1.4542/SUS630/AISI630;
F904L/NO8904/1.4539;
725LN/310MoLN/S31050/1.4466
253MA/S30815/1.4835
Nickel alloy steel:
Alloy 200/Nickel 200/NO2200/2.4066/ASTM B366 WPN;
Alloy 201/Nickel 201/NO2201/2.4068/ASTM B366 WPNL;
Alloy 400/Monel 400/NO4400/NS111/2.4360/ASTM B366 WPNC;
Alloy K-500/Monel K-500/NO5500/2.475;
Alloy 600/Inconel 600/NO6600/NS333/2.4816;
Alloy 601/Inconel 601/NO6001/2.4851;
Alloy 625/Inconel 625/NO6625/NS336/2.4856;
Alloy 718/Inconel 718/NO7718/GH169/GH4169/2.4668;
Alloy 800/Incoloy 800/NO8800/1.4876;
Alloy 800H/Incoloy 800H/NO8810/1.4958;
Alloy 800HT/Incoloy 800HT/NO8811/1.4959;
Alloy 825/Incoloy 825/NO8825/2.4858/NS142;
Alloy 925/Incoloy 925/NO9925;
Hastelloy C/Alloy C/NO6003/2.4869/NS333;
Alloy C-276/Hastelloy C-276/N10276/2.4819;
Alloy C-4/Hastelloy C-4/NO6455/NS335/2.4610;
Alloy C-22/Hastelloy C-22/NO6022/2.4602;
Alloy C-2000/Hastelloy C-2000/NO6200/2.4675;
Alloy B/Hastelloy B/NS321/N10001;
Alloy B-2/Hastelloy B-2/N10665/NS322/2.4617;
Alloy B-3/Hastelloy B-3/N10675/2.4600;
Alloy X/Hastelloy X/NO6002/2.4665;
Alloy G-30/Hastelloy G-30/NO6030/2.4603;
Alloy X-750/Inconel X-750/NO7750/GH145/2.4669;
Alloy 20/Carpenter 20Cb3/NO8020/NS312/2.4660;
Alloy 31/NO8031/1.4562;
Alloy 901/NO9901/1.4898;
Incoloy 25-6Mo/NO8926/1.4529/Incoloy 926/Alloy 926;
Inconel 783/UNS R30783;
NAS 254NM/NO8367;
Monel 30C
Nimonic 80A/Nickel Alloy 80a/UNS N07080/NA20/2.4631/2.4952
Nimonic 263/NO7263
Nimonic 90/UNS NO7090;
Incoloy 907/GH907;
Nitronic 60/Alloy 218/UNS S21800
The blind flange is also called the blind plate, which is called the flange cover. It is a flange without holes in the middle to seal the pipe plug. There are many kinds of sealing surfaces, such as plane, convex, concave convex, tenon groove surface and ring connection surface.
Blind Flange,Stainless Steel Flanges,Stainless Steel Blind Flange,Forged Blind Flange
HeBei GuangHao Pipe Fittings Co .,LTD (Cangzhou Sailing Steel Pipe Co., Ltd) , https://www.guanghaofitting.com
