1. High heat transfer efficiency
Due to the spiral channel of the Type III detachable spiral plate heat exchanger, fluid flows inside the channel. A fixed distance column or punched fixed distance bubble is welded on the spiral plate to maintain the width of the spiral channel. Under the centrifugal force of the spiral flow cloud, the fluid can generate turbulence at lower Reynolds numbers. Considering that the pressure drop should not be too large, it is important to choose the channel width and fluid flow rate reasonably. When designing, a higher flow rate can generally be chosen (the allowable design flow rate is about 2m/s for liquids and about 20m/s for gases), which can increase the dispersion of the fluid, ensure good contact, and improve the heat transfer efficiency of the spiral plate heat exchanger. In recent years, many domestic units have measured and compared the heat transfer coefficients of spiral plate and tube heat exchangers. For example, in the auxiliary ammonia condenser of a refrigeration unit, a Type III detachable spiral plate heat exchanger with a heat exchange area of F=30m² is used instead of a tubular heat exchanger with a heat exchange area of F=75m², doubling the efficiency. For example, in the ammonia synthesis tower of a small fertilizer plant, the original tubular structure with a heat exchange area of F=30.9m² was replaced by a Type III detachable spiral plate heat exchanger with only F=15.5m², which doubled its efficiency.
2. Can effectively utilize the pressure head loss of fluids
The fluid in the Type III detachable spiral plate heat exchanger, although there is no drastic change in flow direction or pulse phenomenon, has a longer spiral channel and fixed distance columns welded on the spiral plate. In general, the fluid resistance of this type of heat exchanger is higher than that of the shell and tube heat exchanger. However, compared with other types of heat exchangers, due to the uniform spiral flow of fluid in the channel, its fluid resistance mainly occurs in the friction between the fluid and the spiral plate and the collision of the fixed distance column. This resistance can cause fluid turbulence, thereby increasing the heat supply system. This enables the Type III detachable spiral plate heat exchanger to effectively utilize the pressure head loss of the fluid.
3. Not easily clogged with dirt
In recent years, many studies have focused on the issue of fouling in heat exchangers, as fouling has a significant impact on the heat transfer efficiency of heat exchangers. In the Type III detachable spiral plate heat exchanger, due to the medium passing through a single channel, its allowable speed can be higher than other types of heat exchangers, and dirt is not easily deposited. If dirt is deposited in a certain area of the channel, the cutting area of the channel will decrease. At a certain flow rate, if the cross-sectional area decreases, the local flow velocity will correspondingly increase, which has a flushing effect on the dirt area. In a shell and tube heat exchanger, if one heat exchanger tube has dirt deposition, the local resistance of this heat exchanger tube increases, the flow rate is limited, the flow rate decreases, and the medium is diverted to other heat exchangers, causing the resistance of each heat exchanger tube to rebalance. This makes the flow rate of the heat exchanger tube with dirt deposition lower and lower, making it more prone to scale deposition and complete blockage. The inner diameter of shell and tube heat exchangers used in chemical plants and refineries often has fouling deposits, which can easily lead to tube blockage. However, in Type III detachable spiral plate heat exchangers, due to the self flushing effect, the fouling formation rate is about 1/10 of that of shell and tube heat exchangers.
When blockage occurs, acid washing or hot water cleaning is commonly used abroad, while steam blowing is mostly used domestically, which is more convenient and efficient than hot water cleaning.
4. To improve the heat transfer efficiency of Type III detachable spiral plate heat exchanger, it is required to increase the heat transfer driving force by utilizing low-temperature heat sources and accurately controlling the outlet temperature. When two fluids are operated in full countercurrent in a spiral channel, the logarithmic average temperature difference between the two fluids is large, which is beneficial for heat transfer. Based on the empirical data used in the design of the heat exchanger, the Type III detachable spiral plate heat exchanger allows for a low minimum temperature difference and can still perform heat exchange even with a temperature difference of 3 ℃ between the two streams. Due to the low allowable temperature difference, countries around the world use this type of heat exchanger to recover low-temperature heat energy.
The Type III detachable spiral plate heat exchanger has two long uniform spiral channels, where the medium can be uniformly heated and cooled, allowing for precise control of its outlet temperature.
5. Compact structure
A Type III detachable spiral plate heat exchanger with a diameter of 1.5m and a width of 1.8m has a heat transfer area of up to 200m², and the heat transfer area per unit volume is about three times that of a shell and tube heat exchanger.
6. Reliable sealing structure
The currently used Type III detachable spiral plate heat exchanger adopts welded sealing (non detachable) and end cap compression (detachable) at the two channel ends. The non detachable type ensures welding quality while preventing internal leakage between the two media. The detachable ends are compressed with end caps, and there is an integral sealing plate on the end caps. As long as the two ends of the spiral channel are processed smoothly, it can prevent the same side fluid from flowing from one circle to the other.
7. Low temperature difference stress
The characteristic of Type III detachable spiral plate heat exchanger is that it allows expansion. Due to its two longer spiral channels, when the spiral plate is heated or cooled, it can stretch and contract like a mainspring in a clock. And between each coil of the spiral body, one side is a hot fluid and the other side is a cold fluid, with the outer ring in contact with the atmosphere. The temperature difference between the spiral bodies is not as significant as the temperature difference between the heat exchange tubes and the shell in a shell and tube heat exchanger, so there will be no significant temperature difference stress.

Equipment model	Nominal heat exchange area m²	Outside diameter D	Equipment height	Center distance of support screw holes φ≈mm	Channel Spacing mm	Take over nominal diameter Dg	Flow rate 1mcs processing capacity m³/h	Equipment weight Kg
Ⅲ 6B4-0.5/350-6	4	334	1155	605	6	60	10	189
Ⅲ 6B4-0.5/450-10	4	388	1205	660	10	80	17.3	223
Ⅲ 6B5-0.5/450-10	5	401	1205	672	10	80	17.3	261
Ⅲ 6B8-0.5/400-6	8	420	1180	691	6	60	10.4	307
Ⅲ 6B10-0.5/550-10	10	564	1255	860	10	80	17.3	450
Ⅲ 6B15-1.0/500-10	15	520	1930	816	10	100	35.3	534
Ⅲ 6B20-1.0/700-14	20	681	1930	1008	14	125	44.2	820
Ⅲ 6B25-1.0/750-14	25	747	1955	1073	14	125	44.2	987
Ⅲ 6B30-1.0/850-14	30	847	2005	1170	14	130	49.4	1181
Ⅲ 6B40-1.0/1000-14	40	981	2080	1441	14	130	49.4	1540
Ⅲ 6B50-1.0/1100-14	50	1103	2130	1560	14	130	49.4	2140
Ⅲ 6B60-1.2/1100-16	60	1160	2330	1637	16	150	63.97	2490
Ⅲ 6B80-1.0/1400-14	80	1413	2280	1873	14	150	49.4	2985
Ⅲ 6B100-1.2/1400-14	100	1390	2480	1850	14	150	59.5	3492
Ⅲ 6B120-1.5/1500-18	120	1517	3030	1997	18	200	96.0	4197
Ⅲ 6B150-1.5/1700-18	150	1700	3130	2151	18	200	96.0	5247