Shock absorbers types

Types of Shock Absorbers. There are eight commonly used commercial shock absorbers. 

Drilco Rubber Type. See Figure 4-169 and Table 4-102 [56]. Shock is absorbed by an elastometer situated between the inner and outer barrels. This shock absorbing element is vulcanized to the barrels. The torque has to be transmitted from the outer into the inner barrel. This tool is able to absorb shocks in axial or in radial directions. There is no need to absorb shocks in the torque because the drill string itself acts like a very good shock absorber so the critical shocks are in axial directions. These tools cannot be used at temperatures above 200°F. Though they produce a small stroke the dampening effect is good [56]. 

Closed-cell sponge is used in a number of articles such as insulation and shock absorbing media and in seals of various types. 

In the most frequently used type of domestic washing machine, the drum containing the washing turns in a suds container. The suds container is spring-mounted in a housing with shock absorbers connecting it to the bottom of the housing in order to attenuate vibrations (Fig. 5.55). 

Hitachi Chemical is considering developments of new applications for its crosslinked PE foam. It has been used as roofing material, cushioning and insulation. It is a closed-cell type and does not absorb moisture or water, is chemical resistant and highly shock absorbant. It is easy to handle and may be processed using conventional equipment. Applications are expected to widen to meet future needs. 

The outer tube can be made from various types of tubing, pipe, etc., the only requirements being that it is fairly stiff and consistently round for its entire length. Automobile shock absorber bodies contain material well... 

Pressurized accumulators contain compressed gas on one side of a piston, flexible diaphragm, or bladder. On the other side is the fluid which is discharged as necessary to an external system, normally to provide power. If a piston rod is added to a piston-type accumulator and the system is closed, it becomes a shock absorber using the fluid under pressure to absorb repeated shocks or sudden impulses. 

Not all types and grades of POs foam easily or with the same kinds of bubble or blown-cell sizes and stmctures. This variability is an advantage in a way, since it allows different kinds of PO foams to be blown for different purposes. Opencell, sponge-like foams are usefiil in shock-absorbing applications, for example, while a closed foam cell stiucture is effective for pipe and cable insulation [3-3]. 

However, when subjected to a 300 P temperature range, the glass lenses frequently broke. Increasing the bondline thickness to 10 mils and using a flexible type "C" formulation produced shock absorbing bonds and the lenses now pass the thermal cycle requirements. 

Unbreakable, leak-proof containers that can withstand chemical attack by carcinogens or solvents should be available for transportation of carcinogens. They should be of different sizes to accommodate different types of glassware and should contain absorbent material that can also act as a shock-absorber. 

Type of shock absorber s Range s Recommended Conunents... 

Type of shock absorber Starting force Additional elongation... 

Among the various categories of smart textiles and flexible materials, which include optically, mechanically, chemically, electrically, and thermally activated substances/ stmctures (Tao, 2001), several have shown large opportunities of applications in PPE. This includes wearable electronics, for example, physiological condition, temperature, and humidity sensors, power and data transmitters, and end-of-life indicators, which are the subject of the next chapter of this book. Various types of smart flexible materials have also found their way into PPE, for instance, as responsive barriers, self-decontaminating membranes, thermoregulating layers, and shock-absorbing patches. 

Buffering or shielding, when suitably applied, w ill absorb the effects of disturbing influences. However, this requires knowledge of the type and mode of operation of these disturbances. A typical example of buffering are shock absorbers cushioning the effects of irregularities in the road surface motor vehicle. 

Equation (6.31) gives some indication of how to amplify the yield stress, i. e. by fixing the value of l/h in the valve. For example, if Z = 100 mm and h = 0.5 mm, then APg = 400Tg. This type of manipulation is, of course, familiar to a hydraulics engineer, who often uses a small shear stress to effect a high pressure drop to drive a piston. It is, after all, why shock absorbers and actuators are usually of the piston type rather than of the shear plate variety, and why fluid-based damper devices are preferred to purely electrical types. However the choice of shear plates can significantly reduce shear rate and hence parasitic drag. 

The shock absorber consists essentially of two concentric cylinders, one cylinder being tapered to orifice the annulus between its surface and the piston. The control drive rod passes through the inner cylinder, and the piston operates between the inside diameter of the outer cylinder and the outside diameter of the inner cylinder. Oil seals of the O ring type prevent the escape of oil between the piston and cylinders. 

The analytical unit of the spectrometer comprises a vibration damping platform suspended on shock-absorbers. Mounted on the platform are guides of the wedge slide type, which carry the driver, shielding screens, collimator to form narrow directed plane-parallel radiation beams, proportional counter and scintillation detector. A narrow plane-parallel y-ray beam from the source rigidly attached to the driver is formed by the slit collimator and, through the entrance window of the dual detector, falls on the sample. The y-radiation is reflected from the sample surface and passed through the exit window of the dual detector and slotted mask (screen), and detected by the scintillation detector Dl. 

---