Mold Parting Lock

In double parting surface and multi-parting surface injection molds, a certain mechanism is required to separate the mold in a certain order and distance when opening the mold, so as to complete the mold opening in sequence. This mechanism is called Parting Lock Sets, or called Parting Lock Sets. Mold opening device, Latch Lock, Latch locking device, etc.

There are many structural forms of Parting Lock Sets. Now we mainly introduce frictional type, spring-type, magnet type, Guide pillar type, swing hook-type, Sliding type etc. Below we will briefly introduce several latch locks.

1. Friction type parting lock:

Nylon parting lock is the most commonly used form of friction Latch lock. It is a simple, convenient and practical method, especially suitable for medium and small injection molds.

It consists of a nylon sleeve, a tapered bolt and a fixed-distance tie rod. It adjusts the friction between the template and the nylon sleeve by locking the tapered bolt. It can ensure that the runner plate and the panel and the fixed template are opened before the fixed template and the movable template are opened.

The precautions of Nylon parting lock are as follows:

•  The Nylon bush of the Nylon parting lock should be embedded in the movable template 3mm
• The opening of the fixed template hole should be rounded R and polished to prevent the Nylon parting lock from being scratched. If the chamfer is made of a bevel, the surface of the Nylon bush will be easily ground and reduce the service life of the Nylon parting lock.
• An exhaust device should be added to the bottom of the fixed template hole
• The inner hole of the fixed template that matches with Nylon bush should be polished
• Do not add oil to the Nylon parting lock, because adding oil will reduce the friction. There is no need to lock the screws too tightly during use.
• Determination of the number of Nylon parting locks: 12*4 in diameter for molds weighing less than 100kg, 16*4 in diameter for under 500kg, 20*4 in diameter for under 1000kg, and more than 6 if it exceeds 1000kg.

Advantages of Nylon parting lock:

•  Simple structure and convenient maintenance
•  The price is cheap

Disadvantages of Nylon parting lock:

• Unreliable performance and short life span
• Not resistant to high temperatures. Although our company also has products that can withstand temperatures exceeding 200 degrees, higher temperatures will accelerate mold failure.

Nylon parting lock can be produced by many domestic manufacturers. The price is not easy, the quality is uneven, and the performance gap is huge. I suggest that if your mold must choose Nylon parting lock, consider choosing THREEUP’s high temperature resistant style, which will greatly increase the life of Nylon parting lock, Reduce the risk of mold maintenance.

2. Spring lock type parting lock:

When the mold is opened, the cylindrical pin presses the lock core   under the action of the spring, and the fixed template and the movable template move together under the action of the lock seat. Under the action of the parting surface of A, the parting is finished, and finally under the action of the mold opening force, the pull rod is forced out of the lock seat, and the parting surface of B is parted to complete the mold opening action. It usually needs to cooperate with the distance mechanism (distance screw) to realize the orderly parting of the mold distance. This structure can adjust the mold opening resistance by adjusting the spring compression. This type of parting lock is used for small and medium-sized molds, where the fastening force is not large and the reliability is not very high.

Advantages of spring type parting lock:

• The spring parting lock has a simple and compact structure, and the processing volume of the mold blank is not large, and it can be installed on the mold at will.
• The installation space is small, so as to reduce the chance of interference with other parts on the mold base. The spring-type latch lock method of controlling the mold opening stroke is more flexible, which can be achieved by adding a limit stop on the mold base.
•  The price is relatively cheap.

Disadvantages of spring parting lock:

• The spring-type Latch Lock relies on the slingshot to press the steel ball to fit the control rod to achieve the lock, so the fastening force is not easy to control, and the phenomenon of unhooking before the required stroke occurs, and the reliability is not high.
• The pulling force is not easy to adjust.
• The size of the pulling force is mainly determined by the internal spring, which is easy to fail under heavy pressure.

Common spring type Latch Lock: Taiwan’s B\C type, LPL, MISUMI’s MPLK series,

3. Magnet-type parting lock

Two lock modules are mainly made of special permanent magnetic materials. When the three-platen mold is opened, the two lock modules are first drawn together by their own pure permanent magnetic force, so that the fixed mold template and the movable mold template are temporarily immobile. When the fixed mold seat plate and the runner push plate have reached their limit positions successively, And finally rely on the system’s pulling force to exceed the magnetic limit of the magnet-type parting lock to separate the fixed mold template and the movable mold template to achieve the sequence of mold opening. When you want to adjust the magnetic force of the magnet-type parting lock, you only need to open the gap between the two latch blocks to achieve the required magnetic force. The installation is simpler, faster and more convenient. It only needs to be installed on the side of the fixed mold template and the movable mold template of the mold. There is no precision requirement. It does not need to be processed on the surface of the fixed mold template and the movable mold template. This shortens the mold manufacturing cycle. The accuracy has no effect.

Advantages of Magnet-type parting lock:

• It has good temperature resistance and is not affected by temperature rise and drop.
• Permanent magnetic force mold locking, no external interference, better performance.
• It has a long service life and does not need to be replaced. The magnetic force attenuation will not exceed 1% within five years.
• This is an environmentally friendly product, easy to load and unload, a set of magnet-type parting lock can be used in different molds and recycled.

Disadvantages of Magnet-type parting lock:

• The positioning is not accurate enough
• Unable to control the mold opening sequence
• The force required to open the mold is the suction force of the magnet itself. If the mold is too small, the tightness of the mold will not be strong, and if it is too large, a larger injection molding machine force is required.

Magnet-type parting locks are mainly from Japanese and Taiwanese companies, among which MISUMI’s MLK and MLKC are relatively good, and most of the products of domestic companies can achieve the same effect and the price is more advantageous.

    4.Guide pillar parting lock

Guide pillar parting lock is also called Mold opening device. The latch lock is mainly composed of the following components, the main bushing, the plunger, the stop block, and the spring. It is installed inside the mold and used to control the opening and closing sequence of the mold parting surface during mold opening and closing; in the mold clamping state, the relative position of the plunger and the main bushing is locked by the stop block; When the parting surface is opened, the plunger and the main bushing move together to ensure that the second parting surface is completely closed; when the first parting surface is completely punched (that is, the first mold opening is completed), The stop block is displaced into the groove of the main body, and the plunger is released while locking the relative position of the main body bushing and the main body, so that the plunger is safely separated from the main body bushing; the second parting surface begins to open until it is completely separated (completely open) Mode state).

 Benefits of Guide pillar parting lock:

• It is installed inside the mold to avoid the conflict between the water transport device and the externally installed parts.
• It saves space without affecting the overall appearance of the mold.
• It can prevent the mold from being damaged by accidental collision during transportation.
• Mold opening device also has the function of reset mechanism and double ejection device.

Disadvantages of Guide pillar parting lock:

• Install the inside of the mold, it is not suitable for maintenance
• The price is more expensive

Commonly used Mold opening device models are: Z3 from STRACK, Z173 from DKL and HASCO from DME

  5.swing hook-type Parting Lock

When the core pulling force is large, the swing hook-type Parting Lock can be used. It is generally installed on the outside of the mold. The structure mainly includes a fixed distance parting mechanism composed of pull rod (fixed distance screw), swing hook, rotating shaft, stopper, spring, etc., The swing hook is equipped with a spring and is fixed on the swing hook seat with a rotating shaft, and at the same time, the swing hook is positioned with a positioning pin. When the mold is opened, the swing hook is tightly hooked to the stopper on the movable template under the action of the spring, forcing A to separate and separate first, continue to open the mold, and under the action of the pull rod (fixed screw), the swing hook rotates around the axis of rotation When the stop is disengaged, the parting of the parting surface A is finished, and the parting surface of B is parted under the action of the mold opening force to complete the mold opening action. Here the tie rod also functions as a distance screw.

The advantages of swing hook-type Parting Lock:

It is installed on the outer side of the mold, it is safe and reliable, easy to install and maintain, and the clamping force is large, suitable for all kinds of large, medium and small molds;

Disadvantages of swing hook-type Parting Lock:

Swing hook-type Parting Lock is currently widely used in the market, especially in the European and American mold markets. Commonly used swing hook-type models are: GS from CUMSA, Z171, Z170, Z173, Z174 from HASCO, Z4 from STRACK, PL series from MISUMI, and TYPE from PUNCH etc.

6.Sliding type Parting Lock

The sliding type Parting Lock, as the name implies, is controlled by the pull rod sliding on the main body to control the mold opening sequence. Its structure is simple. It mainly consists of pull rod, pull rod fixing seat, main body, cushion block, barb, stroke positioning block, shrapnel, etc., with superior performance, Not affected by component wear, large locking force, safe and reliable, and long service life.

When using, first install the spacer block, and install the spacer block on the template parallel to the parting surface with cup-head screws;

Install the pull rod holder, and use cup-head screws to fix the pull rod holder perpendicular to the parting surface. At this time, you must pay attention to eliminate the gap between the barb and the spacer. You can change the installation position of the pull rod fixing seat by intercepting the length of the pull rod;

Install the main body, and fix the main body on the template perpendicular to the parting surface;

Install the stroke fixing block, the components to be locked have been symmetrically installed on the mold, make sure that they are correctly installed and run normally, and then equipped with pin holes;

The clamping buckle is a precision device, please locate it in kind and install it symmetrically. Use in pairs, install at least 2 sets, or 4 sets. And ensure that the mold opening strokes are consistent. If the strokes are inconsistent or not installed symmetrically, a single set of parting locks will be stressed, and the clamping components will break due to unbalanced forces;

When the mold is opened, the leaf spring will put pressure on the pull rod, and the barb will tightly hook the pad on the movable template, forcing the mold plate A separates first, and continues to open the mold. After the toggle pin meets the fixed stroke block, the barb is forced to lift off the pad. At this time, the mold plate A parting surface is finished, and the mold opening force acts on the mold plate B parting surface Parting to complete the mold opening action.

The benefits of Sliding Parting Lock are:

• Shrapnel design, safe and reliable
• Strong clamping force, suitable for large molds
• External installation, convenient installation and easy maintenance.

The disadvantages of Sliding Parting Lock are:

• Large size, taking up a lot of external space.
• The price is expensive, unless the customer specifies to use it.

The typical representatives of Sliding Parting Lock are:

STRAC’s Z5 series, DME’s KU (KL) series, RABOURDIN standard REP series, etc.

Q&A:

      1.What are the specifications and models of THREEUP’s Parting Lock?

Our company can produce the following standards:

Taiwan: B\C,LP,LBL,LD

HASCO standard: Z170, Z171, Z174, Z173

MISUMI standard; PLS, PLM, PLL, MPLK, MLK, MLKC

PUNCH standard: TYPE-S, TYPE-L

STRACK standard: Z3, Z4, Z5, Z6, Z7

DME standards: KU, KL, DKL

RABOURDIN standard: REP460

PROGRESSIVE standard: RPL

CUMSA standard: GS

      2.There are so many categories of Parting Lock in your company, how do we choose?

This needs to be determined according to your mold structure and mold positioning. Some molds have relatively simple structure, you don’t need to control the mold opening sequence of the template, and the cost is relatively low, so you can choose the cheaper and simple structure of Nylon Parting Lock, spring-type Parting Lock. If your mold customer requirements are relatively high, the design is more complex, and you need to have sequential requirements for the opening and closing of the mold, then you need to choose swing hook-type Parting Lock, Sliding Parting Lock, if your mold’s external space is not enough, you need to lock the latch lock Built into the mold, then choose Guide pillar parting lock

3. Question: What is the quality of your Parting Lock?

We have 20 years of latch lock production experience. We believe that the biggest key to parting lock is the quality of the material, the accuracy of processing, and the control of heat treatment. Fortunately, THREEUP has done a good job in these aspects. We can provide you with product standards that are comparable to those of well-known companies, and can effectively reduce product prices, which can reduce mold costs for you.

4. How to purchase your Parting Lock and is there a minimum order quantity?

Answer: You can initiate an inquiry on this page, or send an email to tao@szthreeup.com for inquiries. We ship by express delivery such as DHL or TNT, and there is no minimum order quantity requirement.