Sand Casting
Equipment
0.75 Ton Intermediate Frequency Melting Furnace, Automatic Moulding Line, Clay Sand Conditioning Line, Crane, Electric Welding Machine, Crawler Shot Blasting Machine, Air Reservoir, Screw Air Compressor, Electric Spark Bead Welding Repairing Machine, AC Arc Welding Machine, Automatic Pouring Machine, Sand Mixer, Hot Core Equipment, Cold Core Euipment
Material & Standard
Carbon Iron, Ductile Iron, Steel Alloys, etc.
ASTM, AISI, GB, DIN, JIS, SAE, UNS, EN, JP
Application
Automotive Industry, Construction Machinery, Mining Machinery, Agricultural Machinery, Marine, etc.
Capability
Weight
0.5-40 kg(1.1-88 lbs)
Roughness
Ra25
Casting Tolerance
CT10-CT12
Wall Thickness
5 mm(0.25") Min
Secondary Operations:
CNC Machining, Milling, Turning, Threading, Drilling, Rolling, Wire Cutting, High Precision Grinding, Re-Shape, Sand Blaster, etc.
Surface: As-cast, Painting, Plating, Black Electro-Phoresis, Dacro Coating, Polishing, etc.
Sand Casting,Sand Casting Parts,Iron Sand Casting Parts,Sand Casting Steel Alloy Parts J.B MACHINERY (NINGBO) CO., LTD. , https://www.jbcastings.com
Four-way valve fault judgment and maintenance
1 Why does the electromagnetic four-way valve do not change direction? How to check and repair? Reasons caused electromagnetic reversing valve does not change: ⑴ solenoid valve coil burned. Cut off the power, with a multimeter R * 1 measurement of electromagnetic coil DC resistance and on-off situation. When the measured value of the DC resistance is far less than the specified value, indicating a partial electromagnetic coil internal short circuit. Should be replaced with the same type of electromagnetic coil, the replacement, should pay attention to not set the coil in the center before the core, can not do power check, or easy to burn coil. ⑵ the piston on the valve drain hole blocked. Piston valve hole diameter of only 0.3mm., Although the hole before the filter, if the cooling system is not clean, it is easy to be blocked, resulting in failure can not be reversed. For this failure can be handled as follows: Repeatedly turn on and off the solenoid coil circuit, the reversing valve for the continuous reversing, in order to wash away dirt. If still unreasonable, remove the reversing valve to flush or replace the solenoid reversing valve. ⑶ valve piston bowl leaked. Will be cooling air conditioner temperature control knob clockwise spin in the end, the air conditioner to stop working until after 3min, low pressure tends to balance the valve to power. So repeated several times, if still invalid, can only replace the new electromagnetic four-way valve. ⑷ valve is not closed right air hole. Electromagnetic four-way valve to the normal commutation, the air conditioner is running in a heating state. At this point, the right side of the valve should be colder capillary, left high-pressure capillary should be hot. If the left and right 2 capillaries are hot, indicating that the valve is not closed right air hole is not tight. Approach is to make the electromagnetic four-way valve energized several times, such as the right is still not tight off the air hole, had to replace the new four-way solenoid valve. ⑸ refrigerant leak. As the refrigerant leaks, so that high and low pressure drop, making the valve reversing difficult. This fault should be leak-checked, repair welding, vacuuming and refueling. ⑹ electromagnetic four-way valve on the capillary blockage. For this failure can also be repeatedly connected to cut off the solenoid coil circuit, the reversing valve for continuous commutation, flushing dirt. If still unreasonable, you can remove the flush or replace the capillary. ⑺ compressor failure. If the condenser outlet temperature is low, the electromagnetic four-way valve on the high-pressure capillary is not hot, indicating the compressor is faulty, it should be regarded as the compressor failure, to be ruled out. 2. How to check the electromagnetic four-way multimeter with multimeter? Multimeter can be measured four-way valve coil resistance. When the voltage is 220V, the electromagnetic valve solenoid resistance value of about 700Ω (ambient temperature of 20 degrees). If the coil resistance is zero, the coil is short-circuited; if the coil resistance is infinite, the coil has been disconnected. 3. Four-way valve common fault: lack of flow, poor change. The reasons for the lack of flow: ⑴ system leakage, lack of refrigerant. ⑵ low temperature, lack of refrigerant evaporation. ⑶ four-way valve and the system does not match, that is, the flow of the selected four-way valve system capacity and small. ⑷ air conditioner reversing time. General system design for the compressor downtime after a four-way valve to reverse, when the high and low voltage tends to balance, commutation to the middle position will stop, the four-way valve is not in place, the main slide valve stopped in the middle position, under The second start, due to the role of intermediate flow caused by insufficient flow. ⑸ lack of flow when the compressor starts, the inverter is more obvious. Reasons for the poor: ⑴ coil disconnected or voltage does not meet the coil performance requirements, resulting in pilot valve spool can not move. ⑵ due to external reasons, the pilot valve part of the deformation, resulting in spool can not move. ⑶ due to external reasons, the pilot valve capillary deformation, lack of flow, can not form the pressure difference required for the commutation can not be action. ⑷ due to external reasons, the main valve deformation, the piston was stuck and can not move. ⑸ debris within the system into the four-way valve stuck piston or the main spool and can not move. ⑹ brazing pipe, the main valve body temperature exceeds 120 degrees, the internal parts of the thermal deformation can not move. ⑺ air-conditioning refrigerant leak, lack of refrigerant, the pressure difference required for reversing can not be established and can not move. ⑻ Compressor refrigerant circulation can not meet the necessary flow of four-way valve commutation. ⑼ When the speed of inverter compressor is low, the necessary flow needed for commutation can not be guaranteed. ⑽ scroll compressor makes the system produce hydraulic impact caused by four-way valve piston is damaged and can not move. Chuanqi discrimination and maintenance: ⑴ touch the following three-way four-way valve tube, if they are fever, indicating the four-way valve is not in place, in the middle of a string state. fZX appliance repair ⑵ can also use a small piece of magnet, when the small magnet does not move when commutation, it also shows a string of gas. Filling the system with a certain amount of refrigerant will divert it into place. Not commutation (the failure of more performance is not cooling or heating) discrimination and maintenance: ⑴ lack of refrigerant (only the use of system pressure discrimination is not comprehensive). ⑵ leak fluorine. ⑶ body or capillary deformation. ⑷ coil off power is normal, the voltage is normal. ⑸ to determine the pilot valve with or without action: the coil off when a "da da da" spool impact sound, indicating the normal pilot valve action. At this point the best four-way valve is energized to hear the sound. ⑹ Pilot valve action is normal, the main valve body does not move, indicating that the minimum required four-way valve for the action pressure difference is not established, the system filled with refrigerant. ⑺ hydraulic impact. May be a. Four-way valve installed in the wrong direction; b. The use of a scroll compressor; c. Winter temperature is too low; d.