Hi, I am Moldtek and I want to explain to you how a dispenser pump works for no good reason. Ok there is always a reason to understand how stuff works. So let me start with WHY I was fascinated by these pumps first.

I am a curious chap. I love tearing things apart and coming up with new and better stuff. But the more important REASON here is that I am starting my own machines to start making these pumps right from scratch, here in Hyderabad, India. I am going to churn out 10 Million of these bad boys starting from October ’20 and without even a small scratch (100% automated and online checked). Now let me dive into the HOW part.

How a dispensing system works

First rule – Any flow of material requires an inlet and an outlet. So during dispensing, when one valve is open, the other should be closed. The why of that comes later.

Second Rule – The ball and spring are never in contact – The ball acts as a valve to open/close path. Air venting should be properly enabled.

Let’s consider the basic LOCK DOWN pump which is majorly imported from China for our lotions, sanitizers, shampoos and hand washes. The following 6 molded parts make the present pump.

Pimp Dispensing Mechanism

Priming – 2 steps.

1st step (Valve1 opens Valve2 closed) is the push – the piston assembly (Rod plus piston) moves to compress the spring and the air in chamber escapes out through Valve1

2nd step (Valve1 closes Valve 2 opens) is when you release – On the way back, as valve1 is closed, air can’t move in to fill the space. So, the ball is drawn upwards allowing the product into the dip tube and subsequently filling the chamber.

After the spring returns the piston and actuator into it’s up position, the ball is returned to its resting position, sealing the chamber and preventing the liquid product from flowing back down into the bottle. This initial cycle is called “priming”. Here both Valve1 and Valve2 are closed.

Post priming – When the user presses down on the actuator again, like in step 1, the product that is already in the chamber will be

drawn from the chamber through the holes in piston rod, through the piston guide (stem) and actuator, onto the consumer’s hand. Later when the head is released, the ball allows next batch of material to fill the cartridge.

Some features and functions of the various parts -

Actuator: Generally made of PP plastic and can have many different designs. Often comes with an up-lock or down-lock feature to prevent accidental output. This is one of the components that can set one pump apart from another externally; This is the FACE of the pump and defines its style factor too.

Cap/Closure: This screws the entire assembly onto the neck of the bottle. It is identified as 28-410, 24/415, 33-400 etc. Often made of PP plastic, it is often designed with a rib side or smooth side surface. In certain cases, a shiny metal over-shell can be installed to give the lotion pump a high-end, elegant look. Styles -Embossed, Metal Sheath, Ribbed, Smooth. In some cases, This cap also comes with guide walls and venting arrays on top to bring in a shower-proof feature to the pumps.

Format of cap specification – In a 28-410 pump – ‘28’ represents the neck diameter. ‘410’ represents the GPI thread finish and refers to the height of the cap and the style of threads on the cap and the container.

Gasket/Washer: It is often friction fitted to the inside of the closure/cap and it acts as a gasket barrier on the bottle land area to prevent leakage. This outer gasket can be made from a wide variety of materials: Rubber, LDPE are just two of the many possible options.

Piston guide (Stem), Piston rod, Piston, ball & spring together form the Cartridge/Housing: The transfer chamber that sends the product from the dip tube to the actuator, and ultimately to the user’s hand. Some designs may even have additional housing components that isolate the metal spring from the product pathway; these pumps are generally referred to have a “metal free pathway” feature.

Additionally, the piston guide has a thread matching the threading on the actuator for locking – This makes the assembly transport worthy and leak proof. The critical components in this design are the piston system, housing and type of valves used.

The Moldtek advantage – Moldtek Packaging Ltd (BSE & NSE listed) is a 600 Cr turnover firm with 9 ISO/FSSC certified injection molding units in India. We are market leaders (since 30 years) in Indian rigid plastic pails market supplying to key clientele like HUL, P&G, Mondelez, Asian Paints, Castrol, ITC, RB, etc. We are 100% backward integrated with our own tool-room to develop & maintain moulds IN –HOUSE. Our strength is our technical superiority and ability to deliver six sigma quality levels across all our products.

We are launching 24/410 & 28/410 2 cc dispensing Lock Down pumps and also 28/410 twist-lock pumps with a total capacity of around 10 Million units per month. We are set to launch this from October with 100% automated assembly and online quality inspection.

We put together a strong technical team with a combined experience of >25 years in pumps production, maintenance, QC and assembly. Our improved pump mechanism (new TM/Patent design) would ensur

We would be happy to get back to you on any queries regarding dispensing systems and pumps. Contact us:

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