Marine mooring chock has two types: deck mounted chock & bulwark mounted chock. The material is casting steel ZG230-450 normally. IACS approved quality to withstand all conditions. BV, ABS, LRS, DNVGL, RS, IRS, CCS, KR, NK is available. YSmarines could also provide you with a customized design with CAD drawings.

ISO13729 Closed Chock

The closed chock is made according to the standard of ISO 13729. It is normally applied for the ship which uses wire ropes. The radius of the closed chock surface was designed based on the bending ratio of rope through the chock of not less than twelve times the wire rope diameter. The closed chocks can also be classified into two types by its installation site including deck-mounted closed chock and bulwark mounted one.

ISO13728 Panama Chock

The Panama chocks are made according to the ISO 13728 standard and are normally adopted for ships passing through the Panama Canal, which are normally assisted by locomotives using steel towing wire. They meet normal mooring requirements and Panama Canal requirements. The nominal size the Panama chock is denoted by reference to the width of the opening, in millimetres, which are 310mm and 360mm. It can be classified as deck-mounted Panama chock and bulwark mounted one according to their installation site.

ISO13713 Mooring Chock

The mooring chock is made according to the ISO 13713 standard and is a type of ship’s mooring and towing fitting installed on the shipside to lead the mooring and towing rope from the ship’s inboard to outboard. The mooring chocks are normally adopted for ships which use nylon or other synthetic ropes rather than wire ropes considering the small bending ratio. It has two types depend on its installation including deck mounted one and bulwark mounted one.

Bulwark (EU Type) Towing Chock

Bulwark towing chock also known as EU type towing chock, is installed on the bulwark. It is made of cast steel. The surface of the towing chock is fine polished by 2-layer of shop primer anti-rust painting after sandblasting 2.5and well painted without any bur and the edge is to protect the towing ropes from broken during work. It is similar to NS 2589 chock, not often used in Asian ships.

DIN81915 Panama Chock

The Panama chock is made according to German Standard DIN 81915. The Panama chock, mounted on deck or bulwark, is closed chock which is used to control the position of mooring ropes. The material of the chock is GS-38 (material 1.0420) according to DIN1681 (cast steel). All the edges of the Panama chock must be ground smooth, especially where the rope is in contact with the chock. And it is required to be a blast and primed for the surface treatment. It is used for vessel, tug, cargo ship, military ship, industrial ships etc.

NS2587 Bulwark Mounted Mooring Chock

NS2587 bulwark mounted mooring chock sometimes also called NS2587 mooring pipe, follows the strict quality control system. Its surface is smooth without burs or sharp edges. It helps reduce the friction of the mooring rope. But this type of chock cannot satisfy the requirements of the Panama Canal Commission (PCC). For this chock, it has two optional nominal dimensions. Type A is a welded mooring chock. It is more often used in European countries than in Asia.

For more professional information, please visit on the website of ysmarines.com

The types of wire drawing machine include vertical drawing machine, chain-type drawing machine, roller die drawing machine, horizontal drawing machine and pully-type wire drawing machine, mainly used for drawing steel wire, copper wire and aluminum wire. During the drawing process, the steel wire and the surface of the reel do not slide relative to each other in the circumferential direction of the reel and the surface wear of the two is relatively small. When a certain reel is temporarily stopped in the middle, the customers can still rely on their respective product volume to work as usual. The wire drawing machine has the advantages of simple structure, convenient operation and maintenance, and low manufacturing cost. It has features of large low-frequency torque with stable output, the proportional linkage control with high accuracy, slip compensation function, high-speed accuracy, maintaining constant tension and preventing disconnection.

Vertical Drawing Machine

With the vertical downward working mode of the reel outlet, 1-3 tons of wire can be continuously drawn by vertical drawing machine at a time. The equipment has the dual functions of drawing and take-up. It is suitable for high, medium, low carbon steel, special-shaped steel wire and other non-ferrous metal wire. The machine ia applied for drawing wire in the factories,such as wire-steel factor,metal mesh factory and nail making factory etc. In order to lower residual heat on the surface of the block, the cooling means is installed in inter-wall of the block,the wortle is soaked in cooling water to reduce its working temperature.The vertical drawing machine has precise design, easy operation and the product is made of high quality materials undergoing high abrasion- resistance and low deformation heat treatment process and the machine is endurable with long time preciseness.

Chain-Type Metal Pipe Bar Drawing Machine

Chain-type pipe drawing machine is suitable for the drawing of tube material. The metal drawing machine enters into the center frame mold after passing through the feed end of the raw material. After being clamped by airpower, the chain hook pulls the chain. When the material is drawing, it requires the little vibration on the main body and the uniform stable pulling speed. The best precision of the finished product is achieved. The finished product has a smooth surface and even high quality and it is usually stretched to meet the setting requirements.

Roller Die Drawing Machine

Multiple roller die drawing machine can derust, diameter reduce and straighten various new and old steel wires of Φ8mm-2.6mm. It can reduce the diameter of the steel bar by 3mm at a time without alloy dies, drawing powder, indenter. The wire drawing machine has the advantages of low processing cost, simple operation, easy movement, high efficiency, low noise, etc. It is the ideal equipment for wire drawing processing of scrap steel bars, as well as its products are widely used in hardware, construction and nail making industries.

Multi-Drums Wire Drawing Machine

The wire drawing machine is mainly used for drawing steel wire, copper wire and aluminum wire. It is also called pully-type wire drawing machine and are divided into two drums, triple drums, four drums, five drums, or customized. It has the advantages of high production efficiency, quick drawing speed, small floor occupation, low investment, and easy operation. The machine has a significant energy-saving effect and can save a large amount of electric power for users and is mainly used for weaving net, water tank drawing, construction, galvanizing, etc.

Horizontal Rebar Wire Rod Drawing Machine

Horizontal wire drawing machine enables the steel bar to pass through the wire drawing die from different directions at one time. It can be used in three-ribbed rolling mill. The steel bar after the drawing is directly introduced into the rolling mill for getting a three-ribbed threaded steel bar. The machine is equipped with a 30KW motor. Compared with the continuous pully-type wire drawing machine, the machine has the characteristics of small floor space, energy-saving, simple operation and high production efficiency.

For more professional knowledge, please visit on hrbtinvo.com

To learn the differences among the engine starters, firstly we need to learn how we can start an engine from a state of rest.

You need to start crankshaft of the engine at first, then the piston reciprocates. After that, the combustible mixture work in the cylinders pushes the piston downward to turn the crankshaft. At last, the diesel engine is able to run the working cycles automatically.

Several necessary conditions for starting a diesel engine

1. Diesel

2. Air

3. Sufficient energy to drive cylinder compressed.

Diesel and air are both fuels. The only way to ignite them is to turn the crankshaft to a certain speed.

The device used to turn the crankshaft is starter, which turns the flywheel first, and then flywheel turns the crankshaft.

Several types of starters

Hand Starter

Hand starter is the oldest way to start an engine, and it only needs manpower to crank the shaft to the rated speed. If the operation for the starter is inappropriate, people always get injured. Some small agricultural machines are still using hand starter.

Electric Starter

The electric starter is also called electric motor which can convert electricity into mechanical power, driving flywheels. It is the most popular and cheapest method to start an engine, and it is even available for remote control. The complete electric starter system includes starter motor, battery, cable, charger, and etc. You can find an electric starter almost everywhere, such as an electric starter for the car.

Air Starter An air starter is also called a pneumatic motor, it can convert the pressure energy which compressed by air into mechanical energy. To start a diesel engine, it needs to use external force to turn the crankshaft first. Then the motor reciprocating, pneumatic power drives piston motor and gear motor. The complete air starter system includes air starter, pipe, gasholder, air compressor etc. The complete system of air starter is relatively expensive.

Hydraulic Starter

The hydraulic starter is also called a hydraulic start motor, which can convert hydraulic energy into mechanical energy. A complete hydraulic starter includes a fuel tank, hydraulic starter, manual charging device, filter, manometer, accumulator and control valve. The complete system is also expensive, and it often applies to special working conditions.

Compressed Air Starter

According to the ignition sequence of the diesel engine, a compressed air starter pushed the compressed air into the cylinder during the expansion stroke. And the piston will work with the driving force by compressed air, so that the diesel engine reaches the starting speed and start to work automatically. The complete system has more power than other systems, and it is reliable. You can also use the compressed air for braking, but it is more complicated and heavier than any other starting system. So it is not applicable for small engines.

Spring Starter

Spring starter is a new product for an indirect hand starter, which has been improved. It is also called a mechanical spring starter. It uses a friendly design comparing to the old hand crank starter. You only need to fit and rotate the handle to compress the disc-springs, and the springs will store the energy. After you pull the trip, the system will release the spring’s potential energy to turn the flywheel of the engine. Mechanical spring starter can make sure that the engine can start well even there is out of electricity or other power resources.

As you can see, the spring starter is the best way to start an engine if it is an emergency. I know you are searching for it now, actually you can click Cqstart spring starter to get more info.

You can also contact these people directly:

Sales: Julie He(Ms.),

Tel/Whatsapp/Wechat: +86-13637706003,

Email: sales1@cqstart.com

Marketing: Harland Wang (Mr.),

Email: sundayritian@cqstart.com

For more information, please visit on cqstart.com

The mooring chock is a very important marine equipment. There’re different types of mooring chocks with different standards including ISO, JIS, DIN, NS. SWL will be from 8KN to 3000KN according to your requirements. In the process of mooring ship, it bears huge loads. Usually, the ship bollards and mooring chock are for the whole ship mooring use. The general bow and stern of ship block the bollard fairlead, quantity large. Of intermediate section above without or bollards, fairlead rarely. Fairlead is oblique chock more insurance, because it is closed, the cable will not jump out. The triangle chocks are widely used for small boats and different vessels, such as container vessels, tankers, bulk carriers, tug, dry cargo vessels, etc.

JIS F 2030-1978 Single Point Mooring Pipe

The mooring pipe is a bulwark mounted type and is made according to the standard of JIS F 2030-1978 (Japan Industrial Standards F). It is manufactured by cast steel JIS G 5101. It is a kind of closed chock and is an important part of standard mooring setup, between ships bitts and the mooring bollards. It is used to control the position of mooring ropes on board for large vessels. It has two types, which are oval single point mooring pipe (Type A) and oval inclined one (Type B).

GOST25056 Deck Mounted Mooring Chock

The marine mooring chock is deck mounted type and the manufacturing method should be the requirement of GOST25056 standard. It is a type of ship’s mooring and towing fitting installed on the board to belay the mooring and towing rope, which is widely used in Russia. The yield strength and tensile strength for the material of GOST25056 chock should be more than 216MPa and 412MPa according to the requirements. YSmarines provides you with the best quality deck mounted chock with high quality cast steel for heavy use and high working load.

Triangle Type Mooring Chock

The mooring chocks are triangle types. They will be towed on deck with towing bitts. The shape of the towing chock is a triangle. And the surface of the mooring chocks is fine polished and well painted without any bur. The inside of the triangle type mooring chock can also be covered by 3mm or 5mm SS316L plate to protect the chock and mooring ropes both. They are widely used for small boats and different vessels, such as container vessel, tankers, bulk carriers, etc.

NS2590 Deck Mounted Mooring Chock

NS2590 mooring chocks are deck mounted types and are approved by Panama Canal Commission(PCC). They are welded mooring chocks. The chocks shall be cleaned to Sa2.5 in accordance with Swedish standard SIS 05 59 00 and painted with an anti-corrosive primer. Surfaces coming into contact with the mooring the line shall be smooth. Furthermore, burrs or sharp edges shall not occur.

NS2589 Bulwark Mounted Mooring Chock

The mooring chocks are the bulwark mounted types and are made according to the NS 2589 standard. They are approved by the Panama Canal Commission (PCC). They also are casting mooring chocks.The Nominal Size of 300*250mm is designed as a single chock in PCC and shall be capable of withstanding a strain of 445KN on a towing wire. The Nominal Size of 400*250mm is designated as double chock in PCC and shall be capable of withstanding a strain of 625KN on a towing wire.

JIS F 2017-1982 Panama Chock

The Panama chock is made according to the JIS F 2017-1982 standard and is popular as mooring equipment, which can stand great loads when mooring ships and vessels. It is made of high quality cast steel. It can be either mounted directly onto or into the hull or be supplied with a base plate to be bolted to the plinth. It is used for ships passing through the Panama Canal. There will be two types of the Panama chocks according to their installation site, which includes deck mounted (AC type) Panama chock and bulwark mounted (BC type) one.

JIS F 2007-1976 Mooring Pipe

JIS F 2007-1976 Mooring Pipe is a bulwark mounted chock, which is used to guide or lead the mooring ropes. The material of the mooring pipe is cast steel according to JIS G 5101. Its inside shape of the mooring pipe makes the surface more smooth and can reduce the friction of the mooring ropes. It has two types according to its shape, which includes oval-shaped mooring pipe and circular shape one. The nominal size of the mooring pipe ranges from 150mm~500mm.

JIS F 2006-1976 Open Chock

The Open Chock is made according to the standard of JIS F 2006-1976 and is a special model of the marine mooring chock used for small boats to lead the mooring rope from ship’s inboard to outboard. It also can be applied for military and industrial ships, operating effectively throughout the world. The open chocks have two types according to their material including the SC type one made by cast steel and the FC type made by cast iron. Both types are deck mounted open chock.

JIS F 2005-1975 Closed Chock

The closed chock is made according to the JIS F 2005-1975 standard of the Japanese Standard Association. The closed chock is made of cast steel. Its surface is galvanized, polished and painted to be smooth, which can reduce the friction of the mooring and towing ropes. It is welded at a bow ship. It is used for temporary mooring to guide rope from inboard to outboard a large vessel and applied at the vessel’s bow bulwarks to prevent wear and tear of the mooring line.

For more detailed information, please visit the website of YSmarines marine equipment, in which the users can get the detailed professional knowledge about the marine mooring chock.

Harbin Tinvo Import and Export Trading Co., Ltd (hereafter as TINVO), founded in the year 2007, is a professional trading company in the field of Iron & Steel industry and metallurgy industry. As a bridge between China manufacturers and overseas end-users, we provide a one-stop service of equipment/spare parts procurement and project solution. With the experience and efforts for many years, we have possessed our own supply chain system and loyal client groups in steelmaking machinery, rolling mills parts, castings and forgings, auxiliary equipment of steel plants, etc.

TINVO’s core products contain various types of hot/cold rolling mills like deformed bar rolling mill, strip rolling mill, section rolling mill, rebar straightening machine, wire rod drawing machine, fly shears, cast roll, forged steel roll, wear-resistance sleeves, etc. These products are precisely engineered from fine grade metal and alloy, which are procured from highly trusted, certified and reliable vendors. These products have been mainly served in Southeast Asia, Middle East, Europe and Russia, as well as known for their optimum performance, low maintenance, dimensional accuracy, sturdy construction and user-friendly operation.

Furthermore, TINVO is engaged in offering excellent custom-making design and project solutions for steel smelting, continuous casting and continuous rolling when we keep good partnerships with reputed design institutes and leading-edge factories of electric arc furnace (EAF), induction furnaces, Continuous Casting Machine(CCM). we have appointed a team of highly experienced engineers and technicians. Owing to a sophisticated manufacture facility and advanced management, we have been able to manufacture and supply a wide range of products within the stipulated time.

Why choose TINVO?

Business Principle:

Maximize the business benefits of clients and suppliers as the foothold of our company.

Industry experience:

Have more than 30 strong factories in our supply chain and more than 50 different scales of steel mills user at home and aboard. The best solution and competitive products can be sourced in a short time.

Professionalism:

Have good cooperation with be known steel design institutes nationwide and can provide the client with the most professional design service. Keep long-term contacts with skilled engineers and technicians in the steel smelting plants and rolling mill plants for on-site service of overseas projects.

Sincere Service:

7/24 online service; quick and flexible pre-sales service, standardized in-sales service, and professional after-sales service.

Quality Assurance:

All vendors in our supply chain are qualified in ISO certificates and inspection system in the house, all their products conform to the standards of GB, ASTM, DIN, JIS, etc. Meanwhile, they must have experiences to supply the top-level end-users of steel production and metallurgy. More and more clients upgrade us to a strategic partner, some of them even cooperate with TINVO beyond a decade.

Trade Capacity:

Be familiar with trade policy and logistics; have channels to search for the suitable stuff for international buyers and organize the favorable shipment. The business commission for a middleman is flexible under different trade terms.

Contact Information

Email: inquiry@hrbtinvo.com

Address: Daowai, Harbin City, Heilongjiang, 150050, China.

Telephone: +86 13796661748

Mechanical spring starter can start diesel engines in any special environment releasing the spring’s potential energy. The spring stater motor requires no battery or any other external system, only by hand. It is the ideal backup starter, especially suitable for firefighting, emergency rescue, military, marine and other environments that require high starting reliability. It is also the best starting solution of “black start” or “dead-ship start”.

I guess everyone will work with an engine in daily life, and the most common engines are car engines and motorcycle engines. As we all know, the engine is the source of power that can bring power to modern society.

While every engine must be started by the starter, the common starter is an electric starter that needs a battery to provide energy. Other starting methods like air starter, require an external system to provide energy. All of them rely on external power; once they lack external power, the engine is “dead”.

Although the electric motor is convenient and even automatic, it still needs maintenance. If the starter is out of maintaining or out of electricity, the engine won’t start. It is fine for common situations, but it will cause bad results if it is an emergency.

But how can we avoid this? It is easy to understand the principle and solve the problem. Let’s focus on the engine of a motorcycle, every motorcycle will be equipped with a kicking starter for start engine. It is an easy and simple way to start an engine if the electronic starter doesn’t work.

We can also provide an alternate startup option for other engines, mechanical spring starter. It is based on different principles comparing with the kicking starter of a motorcycle. It can start a diesel engine in any special environment by releasing the spring’s potential energy. Cqstart spring starter, using a simple mechanical mechanism, stores the energy by compressing the springs and releases the spring’s potential energy by pulling the trip lever to turn the engine’s flywheel. The mechanical spring starter can apply to emergency generator sets, lifeboats, firefighting sets, emergency pump sets, construction machines, power plants, irrigation and drainage device, etc.

The flying shear is a kind of shearing machine which performs transverse shearing on a moving rolling stock. It is processing equipment capable of quickly cutting iron plates, steel pipes, and paper rolls. Its performance will directly affect the production efficiency of the rolling production line. It is mainly used to cut medium and small slabs, thin slabs, small sections, hot-rolled and cold-rolled strip. The flying shear machine is generally composed of a shearing mechanism, a mechanism for adjusting the cutting length, a mechanism for adjusting the clearance between the cutting edge and a transmission mechanism. The flying shear can cut the rolled product to a specified length and can cut multiple fixed lengths on the same flying shear, which can meet the requirements of the rolling mill or unit productivity. The speed of the flying shear must be adapted to the speed of the rolling stock to ensure the quality and prevent equipment accidents.

Crank Crop Flying Shear Machine

The type of flying shear machine belongs to the crop shear and it is the indispensable equipment in the continuous rolling mill production line. The basic characteristics of the crank crop shear are that it is frequently started and braked under small inertia, and shearing is achieved under large inertia. The shearing process of the flying shears mainly includes head cutting, tail cutting, cutting (double) length, and accident treatment and sample cutting of the rolled parts on the continuous rolling line. The crop shear mainly includes: crank lever crop shears, rotary crop shears, crank connecting rods and rotary combined flying shears, big gantry flying shears, etc.

Cold Shear

Cold shear plays an important role in the rolling mills. The machine has high strength capacity to cut the product into desired lengths. It adopts a ball screw, linear guide and servo motor to drive the back gauge with high positioning accuracy with integrated steel welded structure, eliminate stress by vibration, with good rigidity. The serials’ connection of the oil cylinder is to prevent the cutting angle changing during the operation of the fly shearing machine. It has the automatic adjustment of blade clearance for accurate, rapid and convenient operation. The adjustable shear angle is to reduce sheet distortion. Motorized back gauge and position display make it convenient and precise.

Disc Multiple Lengths Flying Shear Machine

The flying shear is a rebar cut to length shearing machine which is used in the metallurgical rolling industry and is the key equipment in strip and tangent shearing. It is a high-speed rebar cut-to-length shearing machine used in the metallurgical rolling industry. It is a modern shearing product for rolling rebar. The fixed-length flying shear is arranged between the rebar rolling line and the cold bed nip roller, and its scissor blade has a line speed higher than the rolling line speed by 3-4 m/sec, thereby achieving high-speed rebar shearing.

Crop Shear With Head and Tail Rotary

The rotary crop shear is a conventional flying shear machine.It is widely used by the small and middle steel plant. TINVO is your trustworthy professional manufacturer with high configuration and best price. All steel welded structure, vibrating treatment of ageing for removal of internal stress ensure good rigidity and stability. The integrated hydraulic transmission system gurantee the good reliability. Triple support rolling guide rail is to eliminate gaps of support and enchance shearing quality. The gap of manual adjustment is rapid and accurate. Clearance in between shearing baldes adjusted by hand wheel is quick,accurate and convenient. High stacking accuracy is promised by using individual stacking systems and full automatic type is for easy operation and high output.

Steel Cutting Blade for Hot/Cold Rolling

These steel cutting blades mainly are used for the hot or cold rolled thick sheet of cross-cutting and slitting. The main applications are Large steel plant, non-ferrous metal processing plant, cold-rolled steel plate plant, Strip manufacturers, strapping materials factory, packaging materials plant, steel screen factory, Steel pipe manufacturer, steel slitting equipment manufacturer, etc. The main products are made of high-quality alloy steel such as Cr12MoV, H13, H13Ni, LD, etc., which meets the customer’s small shear burr during use. The more precisely the blades are made, the more accurate steel sheets you’ll get.

Hydraulic Alligator Shear

The hydraulic alligator shear is a type of alligator shear with extremely high-cost performance. The machine has the characters of lightweight and high efficiency compared with other scrap steel iron shearing equipment. Therefore, it has been widely used in mechanical processing and small rolling mills including metal recycling processing plant, scrap car dismantling field, smelting and casting industry, waste materials recycling and processing industry, small and medium-sized steel mills for various cross-section shapes such as round steel, square steel, sectional steel, angle steel, I-beam, Cold shearing and cutting of scrap metal.

TINVO is a professional manufacturer in providing superior quality auxiliary equipment for steel plants, steelmaking machinery, rolling mills parts, etc, the most affordable prices guaranteed.

How can start the engine when it is lack of electricity?

The most popular starter is an electric starter which is convenient and even atomized. But it cannot start an engine once it lacks maintenance or electricity. A mechanical spring starter can solve this issue. It is the perfect solution to start the engine when the electric starter cannot work without electricity. Starting diesel engine at max 50 liters displacement, which only needs manpower.

It can store the manpower energy by compressing the disc springs. After that, the operator can release the energy by pulling the trip lever.

Application Scenes and Details

Firefighting

As diesel engines will drive a water pump for extinguishing, it requires high reliability of diesel engines during firefighting. Once the electric starter breaks down, a mechanical spring starter will be the more reliable backup starter.

Emergency Rescue

Most of emergency rescue sets are movable, usually mothballed in a warehouse. It causes that the sets lack of maintenance for battery. And it is hard to find a backup battery immediately when there is an emergency. However, Cqstart mechanical spring starter is maintenance-free, it hardly malfunctions if the operation is correct.

Marine

The mechanical spring starter can meet the “black start” requirements of the power unit of the ship, if there is an event of electricity loss during the ocean sailing. In the ship regulations, it is required by the SOLAS when the ship is sailing. All ships need to be satisfied that when the whole ship loses power, there should be an emergency unit used to generate electricity for the ship. The mechanical spring starter is designed to achieve the emergency start requirements.

Military Usage

The environment of the wild field is very harsh, and backup resources are insufficient. Generators, vehicles and other vital equipment cannot work, once encountered a shortage of electric starter power. Under this circumstance, you can lean on a mechanical spring starter to start the generators to provide electricity.

Of course, a mechanical spring starter can be used in more than these scenes. All I want to discuss is that the Cqstart mechanical spring starter can apply to varies scenes and different situations, even extremely harsh conditions.

The shipping industry experienced a glorious period from 2000 to 2009 in China, but from 2010, due to the global economic recession, the shipping industry faced the most serious crisis. The situation forced the companies in the field to make the transformation and upgrading. Now the shipping industry is in the phase of transformation. But the all kinds of marine equipment is in demand at any time. YSmarines, based in China, exports the marine equipment to the whole world.

Marine equipment is a general name for many equipments in a vessel. Here we only introduce the simple equipment mainly for accommodation, including marine ladder, marine window, marine door and marine hatch cover. They are necessary parts in one vessel.

Marine ladder is used as the tool to go aboard or ashore, or up and down different deck. The most main products are accommodation ladder, aluminum wharf ladder, pilot ladder, embarkation rope ladder. The accommodation ladder can be manufactured by aluminum or steel. It is usually installed and collected on the shipside, when along with the gunwale released outboard tilted for marine personnel up and down the vessel. It includes ladder frame, upper platform, lower platform, turning device, post, electric or pneumatic winch, safety net and other accessories. The Lowering and hoisting of the ladder is controlled by the winch. Aluminum Wharf ladder also can be called as gangway. It is used as the ladder between the vessel and the dock. It is light, and the handrail is removable. Pilot ladder and embarkation ladder are both rope ladders. They are made of aluminum or hardwood steps and rope. The only difference is that the pilot ladder with anti-twist boards.

Marine window makes the light or the air into the cabins. It is mainly made by aluminum or steel, can be bolted or welded on the bulkhead. The window shape can be changed according to the installment position. According to the function of the window, the designer can decide the window is fixed or open. And the window also can be with electric heating or fireproof. The most widely used window is rectangular window & side scuttle. The rectangular window is used for wheel house, meeting room and deck houses, other superstructures above the freeboard deck. It is fixed or openable. The opening direction is varied. Side scuttle is also called as porthole, normally it includes three parts, the dealight (storm cover), the window frame, the window seat. It has many types according to the different material, opening direction & installment type. we have the detailed introduction for the window opening direction, material, types in our website.

Marine door is the entrance and exit on different cabin or room in the vessel. According the location, it is weathertight, watertight, fireproof, hydraulic sliding watertight door. The marine steel weathertight door is used for the superstructure above freeboard deck or deck house. It is opened and closed by dog clips. The marine steel watertight door is as the doorway in the room or house that has the watertight requirement. It is operated by hand wheel or single lever. Fireproof door has A0, A15, A30, A60, B15, B0 class, used for passage way of fireproof area. Hydraulic sliding watertight door is much complex than other doors, used below water line, normally for engine room. It has the hydraulic system, power system. It also can be made with A60 fire protection. Other marine doors also have aluminum door, gastight door, cabin hollow door, etc.

Marine cover is the opening instrument of, plays the role of seal, protection & supporting the platform partially. The simple hatch cover is opened by the butterfly clip, dog clip, or central hand wheel. It can be weathertight or wathertight, used on cargo deck. Manhole cover is also used widely, it is the entrance for the person to assemble or repair something under the deck. Normally the hatch cover is made by steel.

For all above mentioned marine equipment , ABS, LR, BV, GL, DNV, NK, RINA, KR, NK, RS and CCS can be provided, at the same time, YSmarines also supply all other accessories for these equipment.

The research on the material of cold-rolled work rolls has always been highly valued by the roll industry. From the initial bearing steel, it has gradually developed to 2% Cr, 3% Cr, and 5% Cr section steel. Its development is usually based on the continuous improvement of chromium content. In recent years, semi high-speed steel and high-speed steel roll materials have been developed and there have been some reports on their microstructure and carbide research. The technicians have studied the quenching process of a newly developed forged high-speed cold-rolled work roll material and analyzed the quenching temperature on the structure, grain size, residual austenite and hardness of the high-speed steel rolls, which provides the theoretical and experimental basis for the development of high-end cold-rolled work rolls.

The new type forged high-speed steel roll material used in the test was smelted in a 50kg vacuum induction furnace and then forged at a high temperature to produce a 100mm × 100mm × 250mm billet, which was annealed at 700°C for 4h to obtain the test raw material. The metallographic sample is a 15mm × 15mm × 15mm block, which is heated at different temperatures by a box-type resistance furnace and quenched by air cooling. The hardness was measured using a 660RLD / T Rockwell hardness tester and the residual austenite was detected using an X’perPro X-ray diffractometer, the structure and grain size were measured using an Axiovert200MAT optical microscope, and the carbides were observed using a QUANTA400 scanning electron microscope.

The microstructure of the new forged high-speed steel rolls is lower bainite + bainite + a small amount of martensite + bar carbide + granular carbide. Among them, large bar carbide is precipitated during the solidification of molten steel. Primary carbides, granular carbides are secondary carbides precipitated from austenite during cooling, and the carbide content is 3.6%.

The quenching temperature of the forged high-speed steel roll

(1) The quenching temperature affects the dissolution of carbides. As the quenching temperature increases, the carbide content in the quenched structure of high-speed steel rolls gradually decreases. When the temperature increased to 1200 °C, the granular carbides had been basically dissolved, leaving only a small amount of massive carbides.

(2) With the increase of quenching temperature, the grains of high-speed steel continues to grow. When the quenching temperature exceeds 1040 °C, the grain growth tendency is obvious. The quenching temperature exceeds 1160 °C and the grain size reaches 4.5, then the grain coarsening will become very serious.

(3) As the quenching temperature increases, the residual austenite content increases continuously. When the quenching temperature is below 1080 °C, the residual austenite content increases relatively slowly and then its content increases sharply. When the quenching temperature reaches 1160 °C, the residual austenite content increases to 38%. So the quenching temperature should be lower than 1080°C, considering the control of residual austenite content.

(4) When the quenching temperature reaches to 1040 °C, the hardness reaches its peak value of 64.1HRC. At this time, the matching of the structure, grain size and residual austenite content could be the best for the high-speed steel roll.

(5) The quenching temperature of the new-type forged high-speed steel roll materials should be selected between 1020 ～ 1080 °C.

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