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Quality Advantage

1. Material Requirements for Mechanical parts

(1) Grab top roof beam: Q345B (16Mn)
(2) Rod frame structure: Q345B (16Mn)
(3) Grab bottom roof beam: Q345B (16Mn)
(4) Scoop: If the client has special requirements for the scoop design, we can provide imported wear resistant materials of high quality. Examples in the following:
<1> Bottom blade plate of scoop: Imported wear plate: Hardox500.
<2> Vertical blade plate of scoop: Imported plate: Hardox500.
<3> The scoop front body reinforcement plates use a new technology for high rigidity and abrasion resistant plates. Rigidity is about HRC55-60.
<4> Scoop bottom plate and vertical plate are Q345B with 8mm thickness.
<5> Scoop synchromesh gear: Q345B
<6> Other parts of scoop: Q345B (16Mn).
(5) Pulley: Hot rolled Q345B steel and surface with harden treatment, rigidity>HB400.
(6) Pulley shaft: 42CrMo thermal refining, hardness is about HB250-280 and providing heat treatment report.
(7) Pulley bearing: using well-known domestic brands from three important companies in China: Luoyang, Tile, Ha (Luoyang LYC Bearing Co., Ltd, Wafangdian Bearing Group Corporation (ZWZ), Harbin Bearing Group Co., Ltd). We can also use internationally known brands as per client’s option.
(8) Other shaft: 42CrMo thermal refining, then high frequency quenching process, rigidity is about HRC55-60, and providing heat treatment report.
(9) Press rod bush: ZGMn13.
(10) Center bush: ZGMn13.
(11) Bolts: High strength metric bolt with anti-rust treatment, material of bolts which are lower than M10 is stainless steel.
(12) Opening and closing ropes guide pulley: 42CrMo thermal refining, then high frequency quenching process, rigidity is about HRC55-60, and providing heat treatment report.
(13) Opening and closing ropes guide pulley shaft: 42CrMo thermal refining, then high frequency quenching process, rigidity is about HRC55-60, and providing heat treatment report.

2. Processing Technology

1. When cutting steel plates, numerical control cutting machine will avoid trails by manual polish.
2. Using GMAW (gas metal arc welding) which has small welding stress and welding seal is not easy to break.
3. Bending members will be treated by cold working, which will guarantee they will have precise dimensions and good surface quality.
4. Other technology and craft will be executed by manufacture standards by GB (GB means National Standard of the People’s Republic of China).

3. Paint

1. Painting: The sand blasting treatment is adopted for steel plate surface. The grade of rust removal for the plate surface is Sa 2.5 grades.
2. Bottom paint is epoxy zinc rich primer with 40µm thickness, middle and surface paint is chlorinated rubber paint with 70µm.

4. Structure Requirements:

<1> The open-close steel rope was connected in the grab by wedge socket, which is convenient to assemble and disassemble.
<2> The open-close steel ropes are equipped with stress-balance mechanism, which is to even the strain of the two ropes and prolong the service life.
<3> The bearings of sheaves are labyrinth-design, which can prevent dust from entering, and is convenient to assemble, renew as well as lubricating.
<4> The sheaves have a complete shield, it can prevent goods from entering sheaves and it is easy for steel ropes to pass through sheaves and prevent the steel rope out of the groove.
<5> Press rods structure are optimized to be more compact, with larger rectangle shape. New welding technology can effectively strengthen the connecting welding to avoid any crack resulting from the gap stress.
<6> The climbing ladder on press rods make the lubricating, maintenance and inspection more convenient.
<7> The grab scoop structure is optimized with arc shape, which can effectively reduce dead-weight as well as with more compact structure. After closing, bottom scoop lip gap is≤2mm, and side scoop lip gap is≤4mm.
<8> All connecting pins have dual fail-safe mechanism, with anti-dropping and anti-rotating function.
<9> Ropes guider: There are four rollers, which can prevent steel ropes from being worn effectively.
<10> All bolts, cushion rings and nuts are standard, stainless with high-strength, each fitted with great adhesive to avoid loosening and being corroded.


(1) All moving parts are fitted with sufficient lubrication oil by each-separate oil passage.
(2) The model of all needed lubricating oil nozzles is M10×1.
<1> All oil nozzles are built-in so as to be well protected.
<2> Surface of all grab parts are sand blasted, Sa2.5 grade.
<3> The bottom paint is about 50µm, the middle paint and the surface paint is about 80µm.
<4> Grab Color: Orange or by customer requirement.

6. Document delivery:

(1) General drawing, Drawings of spare parts
(2) List of components
(3) Operation instruction
(4) Certificates