Product Description

Product description

Good Performance NRV NMRV Series Worm Gearbox for Lawn Mower

NRV	030	040	050	063	075	090	110	130	150
B	20	23	30	40	50	50	60	80	80
D1	9 j6	11 j6	14 j6	19 j6	24 j6	24 j6	28 j6	30 j6	35 j6
G2	51	80	74	90	105	125	142	162	195
G3	45	53	64	75	90	108	135	155	175
I	30	40	50	63	75	90	110	130	150
b1	3	4	5	6	8	8	8	8	10
f1	-	-	M6	M6	M8	M8	M10	M10	M12
t1	10.2	12.5	16	21.5	27	27	31	33	38

NRV-NMRV	030-040	030-050	030-063	040-075	040-090	050-105	050-110	063-130	063-150
B	20	20	20	23	23	30	30	40	40
D1	9 j5	9 j6	9 j6	11 j6	11 j6	14 j6	14 j6	19 j6	19 j6
G2	51	51	51	60	00	74	74	90	90
I	10	20	33	35	50	60	60	67	87
b1	3	3	3	4	4	5	5	6	6
f1	-	-	-	-	-	M6	M6	M6	M6
t1	10.2	10.2	10.2	12.5	12.5	16	16	21.5	21.5

NMRV571

Weight without motor:0.7kg

Input size: ( Pm, Dm, bm, tm )

NMRV030

Weight without motor:1.2kg

Input size: ( Pm, Dm, bm, tm )

NMRV040              Output
D H8	b	t
18 (19)	6 (6)	20.8 (21.8)
(..)Only on request  Weight without motor:2.3kg Input size (Pm, Dm, bm, tm)

 

NMRV110

Weight without motor: 35kg
Input size: (Pm, Dm, bm, tm)

NMRV130

Weight without motor: 48kg
Input size: (Pm, Dm, bm, tm)

NMRV150

Weight without motor: 87.8kg
Input size: (Pm, Dm, bm, tm)

Features:

1) Aluminum alloy die-casted gearbox
2) Compact structure saves mounting space
3) Highly accurate
4) Runs forward and backward
5) High overload capacity
6) Stable transmission with reduced vibration and noise

Characteristics:

1. High quality aluminum alloy quadrate case .
2. High efficiency.
3. Small size, compact constructure and light weight.
4. Combination of 2 single-step worm gear speed reducers, meeting the requirements of super speed ratio.

Technical Data:

1. Input power: 0.06kW-15kW
2. Output torque: 7.8-1195N.m
3. Speed ratio: (5-100) 5, 7.5, 10, 15, 20, 25, 30, 40, 50, 60, 80, 100
4. Adapt for IEC, NEMA, SERVO
Materials:
1. From RV25 up to RV105: Aluminium alloy housing.
2. From RV110 to RV150: Cast iron housing.
3. Seal: CZPT Seal from ZheJiang
4. Bearing :homemade Bearing
Color:
1. RAL5571
2. Blue
3. Silver
Quality control:
1.Quality guarantee: 1 year
2.Certificate of quality: ISO9001:2008
3.Every product must be tested before packing

 

General Technical data:

Size number:25,30,40,50,63,75,90,110,130,150

Ratio:1/100-1/5000

Color:blue,silver,RAL5571 color
Material:housing -casting iron- HT200-250#/aluminum worm gear-KK alloy worm-20CrMnTi with carburizing and quenching,surface hardness is 58-62HRC shaft-chromium steel-45#
Packing: Inner pack: use plastic bag a Inner pack: use plastic bag and foam box, outer pack: carton or wooden case 1set/bag/carton or based on customer's requestbearing: CZPT & Homemade bearing
Seal: CZPT seal from ZheJiang
Input power: 0.25kw,0.37kw,0.55kw,0.75kw,1.1kw,1.5kw,2.2kw,3.0kw,4.0kw,5.5kw,7.5kw
Lubricant:Synthetic & Mineral
IEC flange:56B5,63B5,71B5,80B5,90B5,100B5,112B5,132B5
Output form: solid shaft,hollow shaft weight: 0.7-87.8KGSapplication: In industrial machine:food Stuff,ceramics,chemical,packing,printing,dyeing,woodworking,glass and plastics
Warranty:1 year
Recommend Products

 

Gear Reducers For Belt Conveyor

Speed Worm Gear Reducer

HangZhou CZPT Industry Co., Ltd. is a specialized supplier of a full range of chains, sprockets, gears, gear racks, v belt pulley, timing pulley, V-belts, couplings, machined parts and so on.

Due to our sincerity in offering best service to our clients, understanding of your needs and overriding sense of responsibility toward filling ordering requirements, we have obtained the trust of buyers worldwide. Having accumulated precious experience in cooperating with foreign customers, our products are selling well in the American, European, South American and Asian markets. Our products are manufactured by modern computerized machinery and equipment. Meanwhile, our products are manufactured according to high quality standards, and complying with the international advanced standard criteria.

With many years' experience in this line, we will be trusted by our advantages in competitive price, one-time delivery, prompt response, on-hand engineering support and good after-sales services.

Additionally, all our production procedures are in compliance with ISO9001 standards. We also can design and make non-standard products to meet customers' special requirements. Quality and credit are the bases that make a corporation alive. We will provide best services and high quality products with all sincerity. If you need any information or samples, please contact us and you will have our soon reply.

FAQ:
Q1: Are you trading company or manufacturer ?
A: We are factory.

Q2: How long is your delivery time and shipment?
1.Sample Lead-times: generally 10 workdays.
2.Production Lead-times: 20-40 workdays after getting your deposit.

Q3. What is your terms of payment?
A: T/T 30% as deposit, and 70% before delivery.

Q4: What is your advantages?
1. Manufacturer,the most competitive price and good quality.
2. Perfect technical engineers give you the best support.
3. OEM is available.
4. Rich stock and quick delivery.

Q5. If you can't find the product on our website,what do you next?
Please send us inquiry with product pictures and drawings by email or other ways and we'll check.

 

How to Calculate Stiffness, Centering Force, Wear and Fatigue Failure of Spline Couplings

There are various types of spline couplings. These couplings have several important properties. These properties are: Stiffness, Involute splines, Misalignment, Wear and fatigue failure. To understand how these characteristics relate to spline couplings, read this article. It will give you the necessary knowledge to determine which type of coupling best suits your needs. Keeping in mind that spline couplings are usually spherical in shape, they are made of steel.

Involute splines

An effective side interference condition minimizes gear misalignment. When 2 splines are coupled with no spline misalignment, the maximum tensile root stress shifts to the left by 5 mm. A linear lead variation, which results from multiple connections along the length of the spline contact, increases the effective clearance or interference by a given percentage. This type of misalignment is undesirable for coupling high-speed equipment.
Involute splines are often used in gearboxes. These splines transmit high torque, and are better able to distribute load among multiple teeth throughout the coupling circumference. The involute profile and lead errors are related to the spacing between spline teeth and keyways. For coupling applications, industry practices use splines with 25 to 50-percent of spline teeth engaged. This load distribution is more uniform than that of conventional single-key couplings.
To determine the optimal tooth engagement for an involved spline coupling, Xiangzhen Xue and colleagues used a computer model to simulate the stress applied to the splines. The results from this study showed that a "permissible" Ruiz parameter should be used in coupling. By predicting the amount of wear and tear on a crowned spline, the researchers could accurately predict how much damage the components will sustain during the coupling process.
There are several ways to determine the optimal pressure angle for an involute spline. Involute splines are commonly measured using a pressure angle of 30 degrees. Similar to gears, involute splines are typically tested through a measurement over pins. This involves inserting specific-sized wires between gear teeth and measuring the distance between them. This method can tell whether the gear has a proper tooth profile.
The spline system shown in Figure 1 illustrates a vibration model. This simulation allows the user to understand how involute splines are used in coupling. The vibration model shows 4 concentrated mass blocks that represent the prime mover, the internal spline, and the load. It is important to note that the meshing deformation function represents the forces acting on these 3 components.

Stiffness of coupling

The calculation of stiffness of a spline coupling involves the measurement of its tooth engagement. In the following, we analyze the stiffness of a spline coupling with various types of teeth using 2 different methods. Direct inversion and blockwise inversion both reduce CPU time for stiffness calculation. However, they require evaluation submatrices. Here, we discuss the differences between these 2 methods.
The analytical model for spline couplings is derived in the second section. In the third section, the calculation process is explained in detail. We then validate this model against the FE method. Finally, we discuss the influence of stiffness nonlinearity on the rotor dynamics. Finally, we discuss the advantages and disadvantages of each method. We present a simple yet effective method for estimating the lateral stiffness of spline couplings.
The numerical calculation of the spline coupling is based on the semi-analytical spline load distribution model. This method involves refined contact grids and updating the compliance matrix at each iteration. Hence, it consumes significant computational time. Further, it is difficult to apply this method to the dynamic analysis of a rotor. This method has its own limitations and should be used only when the spline coupling is fully investigated.
The meshing force is the force generated by a misaligned spline coupling. It is related to the spline thickness and the transmitting torque of the rotor. The meshing force is also related to the dynamic vibration displacement. The result obtained from the meshing force analysis is given in Figures 7, 8, and 9.
The analysis presented in this paper aims to investigate the stiffness of spline couplings with a misaligned spline. Although the results of previous studies were accurate, some issues remained. For example, the misalignment of the spline may cause contact damages. The aim of this article is to investigate the problems associated with misaligned spline couplings and propose an analytical approach for estimating the contact pressure in a spline connection. We also compare our results to those obtained by pure numerical approaches.

Misalignment

To determine the centering force, the effective pressure angle must be known. Using the effective pressure angle, the centering force is calculated based on the maximum axial and radial loads and updated Dudley misalignment factors. The centering force is the maximum axial force that can be transmitted by friction. Several published misalignment factors are also included in the calculation. A new method is presented in this paper that considers the cam effect in the normal force.
In this new method, the stiffness along the spline joint can be integrated to obtain a global stiffness that is applicable to torsional vibration analysis. The stiffness of bearings can also be calculated at given levels of misalignment, allowing for accurate estimation of bearing dimensions. It is advisable to check the stiffness of bearings at all times to ensure that they are properly sized and aligned.
A misalignment in a spline coupling can result in wear or even failure. This is caused by an incorrectly aligned pitch profile. This problem is often overlooked, as the teeth are in contact throughout the involute profile. This causes the load to not be evenly distributed along the contact line. Consequently, it is important to consider the effect of misalignment on the contact force on the teeth of the spline coupling.
The centre of the male spline in Figure 2 is superposed on the female spline. The alignment meshing distances are also identical. Hence, the meshing force curves will change according to the dynamic vibration displacement. It is necessary to know the parameters of a spline coupling before implementing it. In this paper, the model for misalignment is presented for spline couplings and the related parameters.
Using a self-made spline coupling test rig, the effects of misalignment on a spline coupling are studied. In contrast to the typical spline coupling, misalignment in a spline coupling causes fretting wear at a specific position on the tooth surface. This is a leading cause of failure in these types of couplings.

Wear and fatigue failure

The failure of a spline coupling due to wear and fatigue is determined by the first occurrence of tooth wear and shaft misalignment. Standard design methods do not account for wear damage and assess the fatigue life with big approximations. Experimental investigations have been conducted to assess wear and fatigue damage in spline couplings. The tests were conducted on a dedicated test rig and special device connected to a standard fatigue machine. The working parameters such as torque, misalignment angle, and axial distance have been varied in order to measure fatigue damage. Over dimensioning has also been assessed.
During fatigue and wear, mechanical sliding takes place between the external and internal splines and results in catastrophic failure. The lack of literature on the wear and fatigue of spline couplings in aero-engines may be due to the lack of data on the coupling's application. Wear and fatigue failure in splines depends on a number of factors, including the material pair, geometry, and lubrication conditions.
The analysis of spline couplings shows that over-dimensioning is common and leads to different damages in the system. Some of the major damages are wear, fretting, corrosion, and teeth fatigue. Noise problems have also been observed in industrial settings. However, it is difficult to evaluate the contact behavior of spline couplings, and numerical simulations are often hampered by the use of specific codes and the boundary element method.
The failure of a spline gear coupling was caused by fatigue, and the fracture initiated at the bottom corner radius of the keyway. The keyway and splines had been overloaded beyond their yield strength, and significant yielding was observed in the spline gear teeth. A fracture ring of non-standard alloy steel exhibited a sharp corner radius, which was a significant stress raiser.
Several components were studied to determine their life span. These components include the spline shaft, the sealing bolt, and the graphite ring. Each of these components has its own set of design parameters. However, there are similarities in the distributions of these components. Wear and fatigue failure of spline couplings can be attributed to a combination of the 3 factors. A failure mode is often defined as a non-linear distribution of stresses and strains.