(1) Choose Seal Ring & Seal Groove of Suitable Size
The material of sealing should really be consistent with the hydraulic oil and the hardness of rod mill really should be chosen in accordance with the operating pressure of the method. To get a reliable sealing with long life, suitable compressibility and tensile strength is needed when designing the seal groove. Too high compressibility will boost the compress and friction force, which will accelerate the wearing of the seal ring and reduce its life. While, too low compressibility can not ensure excellent tightness and lead to leaking. O-shape seal ring is widely applied for its simple structure, simple installation process, excellent tightness and reliable performances. For the sake of improving the life of seal rings, it should really be avoided that the central line of seal ring is stretched in designing. Therefore, the selection of seal ring must be based on the international standard and the seal groove should also be designed based on the corresponding standard.
part two Reasonable Structural Design of Parts and Pipelines
When designing the parts, guide angle is needed in case that the seal components be hurt in installation. When install seal ring in the parts which have sharp edges and grooves, we ought to use a protective sleeve in case that the seal components be hurt. When designing the hydraulic pipeline, we will need to keep the distance from the oil tank to the rod mill as short as possible, and keep the bent of the pipeline, especially bent of 90°as few as possible to lower pressure loss and friction force. In the hydraulic method, pipe fittings really should be reduced as few as possible since 30%-40% of leaking is from the pipe fittings.
(3) Control the Oil Temperature in Hydraulic System
When the oil temperature is too high, the lubricating oil film will get thinner, the friction force will be increased, wearing will be increased, aging of the seal material will be accelerated and the seal will get harder and fragile which will finally result into leaking. To improve heat dissipation, we can boost the dissipating surface of the oil tank and separate the inlet and outlet inside the tank with a plate. Temperature of the oil tank must be kept between 55- 65??, 70?? at most. When the temperature of the oil cooled naturally exceeds the limit number, cooling pipe must be added inside the tank or a cooler should certainly be set in the outlet oil line to lower the temperature of hydraulic oil.
(4) Choose Suitable Weld Fittings
Weld fittings that are more often than not used in hydraulic method can be divided into three types, flared, card-sets and welded. These three kinds of fittings have their own benefits each, so it will need to be chosen in accordance with the reliability of performance and economical efficiency. Flared fittings are comparatively cheap. Card-sets fittings can bear large vibration. Weld fittings can be used in occasions of high pressure, high temperature, big mechanical load and powerful vibration.
(5) Control the merchandise Quality Strictly
The size tolerance of the seal groove ought to be controlled strictly and the surface roughness might also meet the specifications. There shouldn't be burr or damaged parts on the brim of the groove. The groove also needs to be cleaned before installation. The size of the seal cover and the hole of the flange cover will need to ensure quality, since too big gap may cause the seal components being squeezed out.
Moreover, we must reinforce maintenance and management in the production process by checking them periodically, repairing and protecting the hydraulic equipments to prevent mechanical vibration and shock pressure, to discover the leaking of the equipment in order to reduce accident and oil leaking. In this way, we can improve the life of the machine and the perfectness ratio of the equipments.