正しいチェーンを選択する方法

The description within this chapter can be utilized when a chain is endlessly engaged for transmission with two sprockets parallel inside their shafts and exact in Driven alignment as illustrated under.
1.Talk to us whenever a chain should be to be utilized for lifting, pulling dollies or remaining engaged which has a pin gear, and so on.
2.When there are actually any regulations or suggestions regarding the choice of chains, decide on a chain in accordance with this kind of laws and the greatest kilowatt ratings (Drive effectiveness) table described under, and choose the one particular using a more substantial allowance.
The chain may be chosen based on the next two approaches:
(one) Selection by drive overall performance
(2) Low-speed variety
The drive functionality strategy considers not only chain stress but in addition the shock load around the bushings and rollers on account of the engagement amongst the sprockets and also the chain, as well as wear of pins, bushings and rollers.
The slow-speed method is applied when the chain is operated at a velocity of 50 rpm or significantly less. Usually, the chain chosen by this system is topic to conditions more severe than that picked in accordance with the variety by drive functionality. Therefore, thoroughly assess the disorders when choosing with this particular method.
Choice by drive efficiency
To start with, the following information and facts is needed.
1.Energy for being transmitted (kW)
2.Speeds of driving shaft and driven shaft (velocity ratio) and shaft diameters
3.Center distance involving driving shaft and driven shaft
(a) Correction of electrical power to become transmitted (kW)
Correction will have to be made to obtain the actual power for being transmitted as the degree of load fluctuates depending on the machine and energy supply made use of, affecting the expected services lifestyle (by way of example, 15,000 hours during the situation of capacities proven within the table of highest kilowatt ratings). The support component proven in Table 1 is definitely an indicator in the load level. The energy to get transmitted (kW) is multiplied by the corresponding service issue to obtain a corrected power.
Corrected power (kW) ＝
Energy to become transmitted (kW) ×Service aspect
(b) Variety of chain size as well as variety of teeth of little sprocket
Utilizing the table of highest kilowatt ratings
When the final results tentatively made the decision as described over are close for the style and design values, the quantity of teeth of tiny sprocket might be finalized with reference to your table of optimum kilowatt ratings. The utmost kilowatt ratings are established anticipating that an limitless chain with a hundred links includes a life of 15,000 hours under the following ailments. (Which is, the breaking with the chain as well as the reduction of bushings and rollers will not arise at a dress in elongation of 2 % or significantly less.)
one.Operation is carried out in ambient temperature (-10°C~+60°C) no cost from dust and dust-containing liquid.
2.There isn’t any corrosive fuel, or humidity, and so forth. to adversely have an effect on the chain.
three.Good lubrication is maintained.
4.The chain is made use of beneath situations of a minimal start-stop frequency plus a fairly steady load.
While in the situation of multiplex chain
Choose a multiplex chain when the capability of a simplex chain is inadequate. The maximum kilowatt rating of the multiplex chain cannot be obtained by multiplying the utmost kilowatt rating of the simplex chain from the quantity of multiplex chain due to the fact the loads will not be evenly distributed among the strands. To the correction component within this situation, see the multiplex chain aspect table. Our regular HI-PWR-S Roller Chains and HI-PWR-SHK Roller Chains can be found as much as triplex.
Remarks for determining the quantity of teeth of small sprocket
Whenever a chain from the minimal chain pitch expected highest kilowatt rating is chosen, comparatively silent and smooth transmission is often attained, and the products can be compact.
However, considering smooth chain transmission, the wear on the chain and sprockets, and so on., it is desirable that the sprocket have 15 or much more teeth, and ideally an odd quantity. Stay clear of 12 teeth, 14 teeth and sixteen teeth. Once the sprocket has 12 or much less teeth, the chain and sprocket heavily vibrate and are exceptionally worn, and transmission will not be smooth. Likewise, prevent a smaller amount of teeth around achievable except while in the case of lower pace devoid of shock.
Shaft diameter
Following the amount of teeth of modest sprocket is determined, multiply it through the speed ratio, and verify irrespective of whether the expected shaft bore can be secured in reference to your highest shaft bore during the table of sprocket dimensions. When the demanded shaft bore is more substantial compared to the optimum shaft bore, boost the quantity of teeth, or decide on a one particular size more substantial chain.
(c) Collection of the amount of teeth of large sprocket
Once the amount of teeth of smaller sprocket is determined, multiply it through the pace ratio to find out the number of teeth of huge sprocket.
Generally, rising the sprocket teeth amount can make the chain bending angle smaller, which increases durability and enhances transmission efficiency. Even so, if your variety of teeth is too massive, slight elongation tends to induce the chain to ride above the sprocket, so hold the maximum amount of teeth at 114 or less.
Speed ratio
A speed ratio refers to the ratio of your velocity of your driving shaft for the velocity with the driven shaft, and usually a speed ratio of 7:one or much less is safe and sound. In case the speed ratio is more substantial than this ratio, the take-up angle of your chain within the compact sprocket decreases, and chain jumping or abnormal wear of sprocket are most likely to take place. If a significant speed ratio is important, two-step pace change could possibly be needed.
Low-speed selection
The low-speed assortment method is applied once the chain operation pace is 50 m/min or significantly less and there is no worry of put on elongation and shock fracture of rollers and bushings.
In low-speed choice, the chain is picked in reference to the tensile fatigue power in the chain. As a result, a chain chosen as outlined by this technique is going to be subject to far more severe disorders than a single chosen according to the variety by drive functionality system. Once the Low-speed selection approach is employed, particular care need to be exercised. The Low-speed assortment method cannot be applied for the connecting links and offset hyperlinks.
(a)The best way to acquire corrected chain tension
Corrected chain tension＝Maximum stress acting on chain kN (kgf)×（service factor）
To calculate the corrected chain stress, determine the exact optimum stress acting around the chain. The shock is deemed to some extent while in the services aspect, however it is not really absolute. Also take into consideration the boost of stress through the inertia of gear a result of beginning and stopping.
(b)Comparison together with the maximum allowable stress of chain
Utilizing the maximum allowable tension from the table of chain dimensions, sprocket tooth aspect and rotating issue in the smaller sprocket listed under, get the corrected greatest allowable tension from your following formula:
Corrected highest allowable tension＝（Maximum allowable tension）×（Sprocket tooth factor）×（Rotating factor）
If your corrected greatest allowable tension is bigger compared to the corrected chain stress, you’ll be able to pick the chain. For that number of teeth and velocity of modest sprocket not stated in Table 1 or 2, acquire the sprocket tooth element and rotating aspect by linear interpolation.