Introduction General part

Determining the time norm.

In mechanical engineering, time is used in a short analytical method to determine the technical time norm. Per-unit calculation time in multi-series production.
T = ; min
Here: t - main time, min
t - auxiliary time, min
t - rest time, min
t - equipment maintenance time, min
T - preparation completion time, min
n- the number of details in the batch, unit
t =t +t +t +t ; here:
t - the time taken to remove and install the part, the time spent fixing the part,
t - time spent measuring a part, time spent operating a machine;
T = t + t ; min
Workers' rest time is taken as x0.05 from operational time;
Equipment service time is taken as operational time x0.06;
N=30000 units T = 4800 min
Table 4.

N:	operations	Main time , min	Auxiliary time, min	To the equipment Service time, min	Rest time, min	Per-unit time, min
1	005	0.56	0.89	0.087	0.0725	1.6095
2	010	0.56	0.76	0.079	0.066	1.465
3	015	1.205	1.35	0.15	0.12	2.83
4	020	0.24	0.65	0.053	0.44	0.98
						6.88

3. 
   Design part.
   
   1. 
      Machine device designing and calculation.
      

In a market economy, the object of production changes frequently. For this reason, specialized, quick-adjustable and universal assembly devices are widely used to reduce the time of technological preparation of production. Nowadays, with the establishment of digital software-controlled machines and flexible production modules based on them, universal adjustable devices are used for them, which provide high accuracy and rapid exchange of blanks. In addition, on the basis of unification and standardization of elements of devices, automated design of devices on the computer is being introduced.
When using devices:
- there is no need to mark blanks before processing;
- productivity increases;
- the cost of the product is reduced;
- working conditions will be improved and safety will be ensured;
- Expanding the capabilities of technological equipment;
- it will be possible to service many devices;
- The number of workers required to manufacture the product will be reduced.
In general, the use of equipment has not only advantages from above, but also dramatically reduces the auxiliary time of the technological process and leads to a reduction in the time of technological preparation of production. When designing the device, the dimensions of the working part of the machine and the elements to which the device is attached are determined: from the theoretical scheme of the base of the ideal being processed; based on the accuracy and cleanliness of the base surface, the type and size of the mounting elements, their number and relative position are determined. The type of device is determined taking into account the base errors, the performance of the device is determined.

We use pneumatic cylinders to tighten our parts in the machining of the given part. At the junction with the piston cylinder and at the exit of the rod from the cylinder, ring V-shaped rubber seals are installed. H11 / d1

So we calculate the tensile force on our device.
Here: k=k₁k₂k₃k₄
k1 = 1,2 – the coefficient taking into account the torque
k2 = 1.1- the coefficient that takes into account the force acting on the axis
k3 = 1.6 - tangential coefficient
k4 = 1.1- coefficient of friction
K = 1,2 1,1 1,6 1,1 = 2,32
Tensile strength relative to the shear force of the device:
W=2,32 1474,56=3421 N
Ensure that the compressive strength of the pneumatic cylinder is W = 3421 N.
The force on the pneumatic cylinder rod is found by the following formula:
Q= p η-q;
Here: p=0,4-0,6 MPa
η = 0.6; the coefficient that takes into account the losses in the cylinder
q = 78 N spring return force
So the effective force at cutting due to the cutting rhythms is P = 1474 N
Assuming that W = Q is conditionally equal, then we calculate the diameter of the cylinder.
D= = = 100 mm

2.