MLA Manual and QC/DC

Manual quick coupling mounted on the Loading Arm.

a. Our manual quick couplings are applicable to flanges within a certain range of thickness. The quick couplings are provided with PTFE or FKM O rings on the sealing surface. A loading arm is provided with 3 to 5 jaws or cam block for easy and convenient alignment with and catch of the flange on a tanker; each jaw or cam block applies basically the same load on the flange.

b. The quick couplings are strong and rigid enough to withstand combined load under the most unfavorable working conditions.

c. A quick coupling is provided with an aluminum blind flange with flat end surface; the flange is removed upon loading or unloading of material and re-mounted after loading or unloading is completed to ensure sound condition of the sealing surface and avoid its exposure to rain and dust.

Hydraulic quick coupling mounted on the loading arm.

a. Hydraulic fast coupling (QC/DC) is a special device mounted on the 3D joint at the front ends of a loading arm for quick connection to the manifold flange of a tanker. The coupling has many distinct characteristics, and may connect flanges of different diameters without using a reducer.

b. The quick coupling (QC/DC) requires no bolt for connection to the manifold flange of a tanker, and can be directly operated by an operator from the dock or the tanker.

c. At the front end of the QC/DC is a plane flange; in the flange, a sealing ring is provided for tight connection to the manifold flange of a tanker. 

d. The QC/DC has its clamping devices distributed in a radial pattern, connected to the base through high-strength spring push rods and assembled together with a revolving ring onto the base. At the full open position, the push rods will form an acute angle with the revolving ring. At the very beginning, revolution of the revolving ring will drive the push rod angle to change and make the clamping devices move behind the manifold flange of the tanker. When the revolving ring moves further, the springs will be compressed to make the compression bars aligned with the clamping devices. When the compression bars moves relative to the clamping devices beyond the center, the system will be locked. On the revolving ring, a position switch is provided to prevent excessive motion of the revolving ring.

e. Main properties and characteristics of QC/DC:
◎All clamping devices must have concurrent motion.
◎The clamping devices must adapt to circumferential thickness change of the flange to ensure transfer of force to the tanker manifold flange during connection and release.
◎The quick coupling shall be able to connect ANSI150 tanker manifold flanges to an extent of two gears below the nominal diameter.
◎The quick coupling must be provided with a mechanical locking device for locking against movement beyond the center.
◎All the clamping devices can be operated by using a hydraulic double-acting cylinder.
◎The hydraulic actuator must be at the full stroke upon connection, regardless of the flange thickness.
◎The coupling can be disconnected from the manifold flange when the tanker becomes imbalanced.
◎The coupling must be provided with a light non-pressure retaining blind flange; when the quick coupling accidentally opens, the flange must be always connected to the coupling.
◎The coupling is provided with an external center piloting device for alignment with the manifold flange center of a tanker.
◎When the electro-hydraulic system fails, a manually operated pump must be provided.
The unit can be lubricated without being disassembled.