In the last issue, we dismantled the two cars that Uncle Ou bought!
Although he deliberately hid the heartache when he filmed **, every time we moved parts, he would say, "Lightly." Slow down.
But in fact, I think it's really fun to dismantle the car. If it weren't for his "hemorrhage", it would be difficult for ordinary people to know that there is such a big gap in the actual cost of two identical models.
Uncle Ou has always said that safety is the conscience of an enterprise, so the safety of the two plug-in hybrid models is also a part that we are very concerned about
Safety comparison – anti-collision beams, fuel tank layout
Engineer Mr. Gao believes that the comparison of safety mainly depends on the design of the anti-collision beam, the force transmission of the chassis structure and the layout of the fuel tank.
Let's take a look at the length of the front and rear impact beams of the two cars:
The anti-collision beams of both cars are made of rigid material, and the Roewe D7 DMH covers a slightly larger area, the main difference is that the Roewe D7 DMH is designed with an energy-absorbing box as a buffer in the rear anti-collision beam part, while the Qin PLUS DM-i does not have this design.
The structure of the energy absorbing box is simple, the cost is not high, but the effect is obvious, it can improve the energy absorption efficiency of the vehicle in the event of a collision, reduce the impact force on the body frame, and can play a better cushioning role in the collision. Mr. Gao said that if there is a lack of energy-absorbing box design, the bumper will form a hard connection with the body skeleton, which is easy to damage the body frame structure in the event of a rear-end collision and increase the maintenance cost.
The charger of the two cars is installed in a different position, and the Qin PLUS DM-i is installed in the spare tire slot of the trunk, which is relatively close to the rear impact beam. The Roewe D7 DMH is mounted above the rear subframe, which is more discreet, farther away from the rear bumper, and has the rear subframe as a cushion, which is much less likely to be damaged in the event of a collision.
Both cars are hybrid models, but when it comes to hybrids, everyone will have a worry, that is, is this car an old platform for "oil to electricity".
First of all, the material and installation position of the fuel tank of the two cars are different.
This is the Roewe D7 DMH, the fuel tank is placed in front of the rear axle, and the fuel tank is a plastic high-pressure fuel tank made of multi-layer composite materials.
This is the BYD Qin PLUS DM-i, the fuel tank is located behind the rear axle, and the fuel tank is made of metal.
The structural difference is still obvious, Mr. Gao said that in 1993, GM designed the fuel tank to the rear axle due to a certain model, and in a rear-end accident, the car *** caused family members to burn, for which it was fined $1.2 billion.
The similar design is similar to the location of the fuel tank of the Qin PLUS DM-i.
Since there was such a precedent before, why would BYD still do this?
Uncle Ou believes that the position of the fuel tank of the two cars is in line with the highest standard, and there is no need to question this.
It's just that once the rear collides, only the rear anti-collision beam can protect the Qin PLUS DM-i, and the rear anti-collision beam does not have an energy-absorbing box, and the strong rear suspension can not protect the fuel tank, and once the metal fuel tank is squeezed and collided, sparks may occur, increasing the risk. As long as you don't encounter a serious rear-end collision, you don't have to worry.
The Roewe D7 DMH fuel tank is farther away from the rear of the car, and the rear impact beam, energy absorbing box, trunk and sturdy multi-link rear suspension all disperse the impact force in the rear. The plastic fuel tank is made of composite materials, which ensures safety and reduces the chance of being hit and crushed by Mars.
The purpose of our dismantling is to let everyone see which of the two cars has a more reasonable safety design, and to know it when buying.
Mr. Gao also pointed out that the battery installation position and wiring harness arrangement of the two cars are also very different, and the lowest point of the Roewe D7 DMH battery is embedded with the side beam 185mm, the lowest point of the BYD Qin PLUS DM-i battery protrudes from the side beam 431mm。
It means that the Roewe D7 DMH battery is embedded in the chassis, and the side beams can play a role in protecting the battery, which is considered at the beginning of the development of the new energy platform, and it is also a structure that cannot be seen on the oil-to-electric platform.
Secondly, the wiring harness will pass through the first channel, and the tubing will be embedded inside the side beam, and the wiring is relatively reasonable to reduce the damage caused by external factors to the wiring harness and tubing.
In contrast, the difference between Qin PLUS DM-i is still quite obvious, the battery will have a protrusion relative to the side beam, the wiring arrangement is also relatively scattered, the chassis adopts half-pack protection, and the protection of the tubing and wiring harness is relatively weak in the event of a collapsed stone.
Mr. Gao also explained that the Roewe D7 DMH has several more beams than the BYD Qin PLUS DM-i in the chassis part, which can better protect the battery pack in the event of a side impact, which is also a unique landmark structural design of the new energy platform.
Based on the above analysis, in terms of platform layout, the two cars do have design differences, Roewe D7 DMH adopts new energy architecture design, chassis flatness, fuel tank position and battery protection are more reasonable.
Is Qin PLUS DM-i an oil-to-electricity platform?
It's hard to say for sure.
NVH comparison - interior materials + sound insulation and noise reduction materials
In the dynamic test drive before the dismantling of the car, Uncle Ou felt that there was a significant difference between the two cars in terms of vibration and noise handling.
Mr. Gao said that everyone often says that NVH refers to noise, vibration and harshness. These three dimensions are determined by the overall performance brought about by the vehicle system engineering. It is not only related to the way the bushing, dual-mass flywheel, and P1 motor are connected to the engine that I have seen before, but also to the chassis painting, the thickness of the window glass, and the sealing process.
The front cabin of BYD Qin PLUS DM-i adopts a single-layer soundproof cotton design, and there is no shock-absorbing material in the lower half of the chassis, while the front cabin of the Roewe D7 DMH has a double-layer design of soundproof cotton and heat-insulating aluminum foil, and the lower part of the body frame has a bottom-coating material, and the overall spraying process is more advantageous than that of BYD Qin PLUS DM-i.
Mr. Gao also said that the door structure can also be seen in sound insulation and noise reduction, and there are four differences between the two cars:
The thickness of the glass is different, the front window glass of the Roewe D7 DMH is 5mm, and the rear window glass is 35mm, BYD Qin Plus DM-i front 35mm, rear 32mm, for use, thicker glass will bring better sound insulation.
Front door glass regulator, Roewe D7 DMH adopts a double guide rail structure, and BYD Qin PLUS DM-i uses a single guide rail structure, which can improve the durability of the vehicle lifting mechanism, as well as the stability and durability when lifting.
In terms of sealing process, the Roewe D7 DMH head road sealing strip is bonded with 3M glue, and the BYD Qin PLUS DM-i is fixed with clips, which will not fit, and the anti-dust and sound insulation effects are slightly inferior to the Roewe D7 DMH.
On the soundproof cotton of the inner lining plate, the Roewe D7 DMH area is larger, Mr. Gao said that the cost of the entire front door, the cost of the Roewe D7 DMH will be about 60 yuan higher, and the gap between the rear door is not large, so the cost difference between the two cars on the four doors is about 200 yuan.
Roewe D7 DMH has 10 speakers in the whole car, BYD Qin PLUS DM-i has 8 speakers in the whole car, and the speaker power of the rear door is 25W for Roewe D7 DMH and 20W for BYD Qin PLUS DM-i, which has more power and better audio experience. The difference in cost for this part will be around 300 yuan.
In terms of door hinges, there is also a clear gap between the two cars:
The door hinges of the Roewe D7 DMH are made of steel structures that are used by many luxury brands. The BYD Qin PLUS DM-i uses a conventional stamped hinge. Mr. Gao said that the cost of this one part alone has reached the cost difference of 40 yuan for the whole car.
Since they are expensive, what is the difference between them?The main thing is intensity.
Mr. Gao said that the national standard requires that the door hinge can withstand 11Longitudinal load of 11 kn and 8A lateral load of 89 kn, which must not be disengaged.
The strength of forged hinges can be more than 3 times higher than this standard;
The strength of the section steel hinge can be higher than this standard 25 times or so;
The strength of the stamped hinge can be up to 2 times higher than this standard.
Therefore, the section steel hinge used in the Roewe D7 DMH can withstand a greater limit of strength than the stamping hinge used in the BYD Qin PLUS DM-i, and some luxury brands such as Volvo, BMW, and Audi will also use section steel hinges for their doors.
In terms of interior, the Roewe D7 DMH is wrapped with a large area of soft materials, and there is even a suede material that is not common in models at this price, and the interior is visually more like a B-class car, and the Qin Plus DM-i interior uses a large area of artificial leather surface and plastic to wrap, and the overall texture is not successful. The cost difference of the interior part is about 800 yuan.
In terms of pocket gear design, the Roewe D7 DMH's pocket gear design is more costly, and at the same time, it can save valuable space in the car. The location of the middle island can be placed without the need for conventional gearboxes, leaving more room for designers to play.
The Qin PLUS DM-i uses a combination of electronic gearshift and ignition, and the logic is more like that of a fuel vehicle.
Mr. Gao also pointed out that the Roewe D7 DMH is equipped with a panoramic sunroof, and the BYD Qin PLUS is an ordinary small sunroof, and the cost gap is about 1000 yuan.
At this point, I have read about the sound insulation and the materials used in the interior, and I have also made a **:
The difference in this part has reached a total of 2340 yuan, which explains Uncle Ou's doubts in dynamic driving, Roewe D7 DMH for noise isolation and vibration treatment, will be better, improve the overall driving and riding quality.
Who is more worth the cost comparison?
At this point, the two cars have been completely disassembled, and the statistical results in terms of cost are as follows:
I have to admit that the current price difference is here, we are still a little surprised, the guide price of both cars is 13580,000 yuan, the discount is about the same, but there is a big gap in the cost we can see.
Mr. Gao believes that Qin PLUS DM-i has a first-mover advantage, and at the time of its birth, it is understandable to use this set of things, even ahead of the opponents at the time, and there is no point of accusation here. Roewe D7 DMH has the advantage of being a latecomer, and has more time and opportunities to study opponents and improve themselves, so it has made more targeted improvements and improvements in structure and materials.
Uncle Ou believes that the first-mover advantage can create word of mouth, but it also gives consumers the inertia of consumption and the information cocoon of word of mouth. In fact, there are many models that have begun to hit the 100,000 yuan level this year, and the Roewe D7 DMH is one of the products that is quite excellent in terms of design and materials.
Either way, both cars are pretty good products. The rhythm of the interrollment between domestic cars is something that the Japanese, Americans, Germans, and Koreans cannot understand and keep up with.
This is the first time we have met you in the way of dismantling the car, in fact, we as primary school students in the dismantling circle, there will definitely be less rigorous and perfect places, and all our content is not objective at all, you can just take a pastime to see, if it can have any impact on your car purchase. That must be your own responsibility!
It's nothing to do with us, see you next time!