Hijet Bit, LLC is the United States distributor of JZ Bits. Our product line also includes PDC drill bits manufactured by PDC Logic, LLC, one of our sister companies.  Hijet Bit is focused on providing products that will be superior in performance and lowering your drilling cost-per-foot.



Hijet Bit, LLC is owned and operated by Tom Waitman. Since the 1950’s, the Waitman family has provided new drill bits, reconditioned drill bits, drilling tools, and other oilfield equipment to the drilling industry. Our successful partnership with Kingdream Public Limited Company (manufacturer of JZ bits) began in 1999. The proven quality and value of JZ bits combined with the knowledge and service experience of Hijet Bit, Inc. has produced a growth rate of JZ bits which is unmatched by any of our competitors.



Here at Hijet Bit, LLC, our business is built on relationships which will result in an exchange of values between our customers, vendors, and ourselves. We have a three-fold commitment to our customers:


1.       We are committed to quality customer service built on the foundation of honesty and work ethic

2.       We are committed to providing an innovative, consistent, quality product which will have a performance level that you can be confident in.

3.       We are committed to provide these products at a price that will lower your drilling cost-per-foot.


PDC Logic Technology


Quick iteration turnaround time allows PDC Logic to achieve the goal of producing the optimum bit for a specific application. This advantage allows PDC Logic a distinguished “edge” over our competition.


Our bits are designed meticulously, combining both logic and technically advanced blade profile philosophies to maximize shearing efficiency of various formation types.











Manufacturing and Engineering Technology



·         Brand new facility located in The Woodlands, TX

·         Mori-Seiki CNC Machines




·         High quality materials

·         Skilled craftsmanship / machinists

·         Innovative temperature and time controlled furnacing system


·         Over 100 years of manufacturing experience from 8 different PDC companies

·         Best known methods are combined with innovative philosophies

·         The end result is industry unique and has yielded zero failures


Cutter pockets and body geometry are CNC programmed from 3D scale models and machined to within a 0.076 mm tolerance.



SolidWorks CAD and MasterCAM CNC




          Currently at 118 different versions and bit iterations.

          Continuous monitoring of performance and dull analysis has yielded top performing products.

          Optimized body geometry and nozzle placement allows for highly effective balling mitigation, cutter cooling, and cuttings evacuation.


          Innovative cutter layouts and bit profile configurations maximize drilling efficiency in vertical, directional, and horizontal applications.

          Cutter spacing, back rake, and side rake values are determined to create a smooth transition in torque response from bit center to gage.

          Asymmetrical blade geometry and unique TCI vibration mitigation yield stable drilling and increased bit life.



          Close cooperative work with the top PDC cutter vendors.

          Ongoing development and improvement.

          Superior diamond bonding quality



          Cutter bevel selection includes meshing the layout philosophies with the application being drilled.

          Aggressiveness and shearing efficiency are maximized while durability is maintained.




          When available, on-bottom parameter data is plotted and compared to formation tops, offset wells, and parameter changes.

          Greater understanding of application limitations allow the design to be iterated and performance increased.

          Dull conditions of the bit act as photograph of the limiting factors.






Personnel are the backbone of any organization and AOSG, PDC Logic and Hejian Xinlong are backed by a highly experienced and dedicated team of professionals, possessing vastly impressive knowledge and experience designing, manufacturing and operating PDC bits. All possessing in-depth industry knowledge and market understanding our teams have been sourced and selected to ensure the company’s continued development and growth.








Gary Jenkins - Senior Optimisation Engineer: Based in Libya and responsible for Technical support in the North Africa region, Gary brings with him a wealth of experience in drilling Completion Engineering, Technical Limit Implementation – Optimization, and Field Supervision of projects.  Gary has significant experience in Planning – Optimisation of drilling projects, in the design and execution of horizontal/directional drilling projects, including under-balanced projects, barge rig and floater operations.


Gary is responsible for assisting clients with Bit Optimisation Studies, drilling optimisation, product application, and developing products for specific client applications to reduce drilling cost per foot.


07/05 – 07/09  

TD Consulting Limited - British Virgin Islands

Senior Drilling Engineer:  Prepared drilling plans, cost estimates, and project management for international projects in Hungary & Romania (2005), and Uzbekistan (Jan 2006 thru March 2009).

02/05 – 06/05   

Independent Consultant thru Sierra Eng. - Denver, CO

Field Drilling Supervisor:  Supervising field operations to drill Almond wells in SW Wyoming and +13,000 ft Mesa Verde wells in Pinedale, Wyoming.

01/04 – 01/05    

EnCana Oil & Gas (USA) - Denver, CO

Drilling Engineer:  North Piceance (NW Colo) over all drilling operations in sub-normally pressured reservoirs for multi-rig program.

09/96 – 01/04    


Drilling Project Engineer:  Working for the following clients in the listed capacity:

01/03 – 01/04                                    

EnCana - Houston, TX & Denver, CO

Drilling Project Engineer:  Consulted on international and domestic US drilling projects.  Evaluated and recommended against joint venture with Pemex in Mexcio.  CBM/Managed pressure optimization project in NW Colorado out of Denver, Colorado office for EnCana

08/02 – 01/03    


Field Drilling / Completion Foreman / Engineer, South Louisiana:  Office Engineer for preparation of cost estimates, drilling and completion plans.  Wellsite Supervisor on barge rig performing drilling and completion operations.

04/01 – 07/02    

BP - Houston, TX

Technical Limit Performance Engineer, Gulf of Mexico- Deepwater:  Co-authored Technical Limit Implementation Guidelines Manual for BP.  Assigned to Deep Water Horizon new-build Semi-submersible.  Travelled on rig from Singapore to Gulf of Mexico.  Rig-site Engineer and member of implementation team to incorporate Technical Limits into the well planning, and daily project management processes.  Specific emphasis on simultaneous operations to reduce the effective daily cost, improve safety and performance.

04/00 – 03/01    


Technical Limits Coach / Drilling Engineer, North Slope and Anchorage, Alaska:  Rigsite coach for Arco / Phillips Alaska on Nabors 16E drilling rig on the North Slope of Alaska and in the Anchorage office.  Member of implementation team to replace morning reporting system with DIMS, including configuration and how to include Technical Limits in the well construction process.  Team designed tools to incorporate Technical Limits into the well planning, and daily project management process, including trouble time analysis and hazard mitigation.

10/99 to 04/00  


Drilling Project Engineer: Houston, TX

Office and Wellsite Engineer / Supervisor.  Primary emphasis on Floating Drilling Operations, Gulf of Mexico.  Prepared offset analysis and cost estimates for turnkey bids.

09/96 – 09/99    


Drilling Project Engineer:  Project Manager and Wellsite Engineer / Supervisor:  Primary emphasis on East Texas Cotton Valley, Travis Peak, and Pettit drilling, completion, and workover projects.  As Project Manager for the Vastar Carthage Project, successful in reducing drilling-completion costs from $1.35MM / well to $0.8 MM / well despite increases in rig rates.

01/90 – 09/96


Staff Drilling Engineer, Midland, Texas (Horizontal Projects in Permian and Williston Basins)

Staff Acquisition Engineer, Staff Reservoir Engineer, Staff Joint Interest Engineer, Staff Production / Completions Engineer


07/88 – 09/89


Summer Engineer for Steamflood, Paso Robles, California – 2 summers.

06/87 – 09/87    


Summer Roustabout for waterflood, Dickenson, North Dakota.

06/86 – 09/86


Summer Roustabout for Eugene Island 316 drilling / production platform, Louisiana / Gulf of Mexico.

06/81 – 03/83    


Roughneck / Floorhand on land drilling rigs.


1983 to 1986                                        Pikes Peak Community College, Colorado Springs, Colorado

Graduated Dec 1989                           B.Sc. Petroleum Engineering Colorado School of Mines

Industry Training

·                                                   IWCF – Drilling Supervisor Certificate – Combined Surface & Subsea BOP Stack

o                          Cert. No. SS52467/US636/09-016 Valid from May 22, 2009 for 2 years

·                                                   IADC WellCap – Drilling/Completion/Workover Supervisor – Surface & Subsea

o                          Issued June 30, 2005     Expires June 30, 2007

·                                                   IWCF – Drilling Supervisor Certificate – Combined Surface & Subsea BOP Stack

o                          Cert. No. SS15116/US206/01041 Valid March 21, 2003 for 2 years

·                                                   BP – required office and offshore in house training courses

·                                                   TransOcean SedcoForex – Safety Assurance Training – 29  courses w/ BP

·                                                   Reach Group – Technical Limit Coach Training

·                                                   Murchison Drilling Schools – Operations Drilling Technology and Advanced Well Control Course -  MMS

o                          Certification at the Supervisor Level, Surface BOPE

·                                                   Prentice Training Company – Advanced Casing Design

·                                                   Maurer Engineering – DEA-44 Horizontal Well Technology School

·                                                   Joshi Inc – Horizontal Well Technology

·                                                   Hilchie – Openhole Log Analysis

·                                                   Hydraulic Fracturing School

·                                                   H2S Training and certification

·                                                   Smith-Cobb – Waterflood School

·                                                   SPE – Reservoir Management Shortcourse

·                                                   Stermoles Economic School

·                                                   Leadership Practices / Advanced Leadership Practices

·                                                   Managing Management Time



·                                                   Society of Petroleum Engineers – since 1987

·                                                   SPE Reservoir Engineering Study Group – Midland – Vice-Chairman 1995-96

·                                                   API

·                                                   United Way – Company Co-Chairman for 1994 campaign drive







Clients of Hijet Bit and Alamia Oil Services Group


Arabian Gulf Oil Company

Zueitina Oil Company




Devon Energy,
















El Paso,





Petroleum Develop,

Berry Petroleum,





Hunt Petroleum,

Vintage Petroleum,


Hejian Xinlong has exported Bits to companies in

GSPLAJ, Japan, Australia, Kazakhstan, Middle East, Mozambique, Algeria, South Africa and Europe.






PDC Drilling Parameters - Best Practice Guide


RPM, Weight on Bit, and Hydraulics for PDC drilling



The continuous encroachment of PDC bits into Roller Cone markets has led to misunderstanding of what drilling parameters to use. It is important to visualize the difference in the mechanical methods of rock removal for both types of drill bits as well as the optimum drilling parameters for each. The removal of rock via compression requires a different set of optimum parameters than the removal of rock via sheering. Understanding the optimum drilling parameters of each of the mechanical methods will lead to increased ROP and bit durability.


RPM - Roller Cone:

When drilling with roller cone bits, the depth of failed rock (depth of cut) due to compression depends on the length of the tungsten carbide insert. Likewise, the area of failed rock (per insert) depends on the shape of the insert. The length and shape of insert vary depending on the strength and type of formation being drilled. In a given application, the optimum length and shape of insert are determined. When drilling, there will be a certain volume of rock removed per bit revolution with the optimized insert geometry. Because of this, ROP becomes dependent on RPM. RPM can be optimized by increasing until premature failure of the inserts occurs (WOB is required to keep maximum penetration). In short, ROP with roller cone bits is maximized when WOB and RPM are at the optimum point where full insert penetration occurs without premature failure.



One of the most important aspects of PDC drilling is to visualize the mechanical side of what is actually occurring. The mechanical side of PDC drilling involves the sheering of confined rock. The shearing of rock, as well as most materials, is dependent on crack propagation, magnitude of applied force, and time duration of the applied force. Crack propagation occurs in the direction of the applied force. In the case of PDC cutters, this direction is perpendicular to the face of the cutter, the applied force is bit torque, and the time duration is RPM.


There is more than one combination of force and time that will sheer a material along the desired plane. Primarily, shearing can be done with a very high magnitude of force over a short time (impact), or a lower force over a longer time. Impact sheering is effective, yet can be damaging to the tool used to sheer the material. If too low force is used over a long period of time, the crack that propagates may tend to wander away from the direction of applied force. The goal is to determine the optimum combination for the type of material being sheered.


With PDC drilling, impact sheering is not desired as it leads to premature cutter damage. Impact sheering can occur during instable drilling and higher RPM. At high RPM, the crack propagating from the face of the cutter is not given sufficient time and leads to a “chunk” of removed rock as opposed to sheared rock. This does not mean that high RPM will always cause impact sheering to occur. If the depth of cut of the PDC cutter is low enough, the required torque is less and effective sheering can occur. However, higher RPM also means higher kinetic energy for the PDC cutters (higher cutter velocity). One of the primary reasons for PDC cutter failure is thermal degradation (heat generation). Higher cutter velocities lead to higher friction amounts which lead to more heat generation (scraping, not sheering). For this reason, many formation types should not be drilled with high RPM (mainly sand stones and carbonates). Still, other formations can be drilled quite effectively with higher RPM without major concern of cutter damage (low compressive strength shales and mud stones). In general, the potential for premature cutter failure is much greater when higher RPM is used.


PDC drilling is most effective when a combination of moderate torque and RPM are used. In a given formation, the goal is to try and maintain a consistent torque environment. Doing this, while staying within + 5 to 10 RPM of a desired value will lead to efficient crack propagation. In most applications involving moderately hard or more abrasive formations, RPM should be kept between 90 and 140. There are many cases where lower RPM (50 to 80) is most effective (hard carbonates, anhydrites, chert, and conglomerates). Likewise, there are also many cases where higher RPM (150 to 180) is most effective (soft shales, mudstones, coal, etc). In general, the 90 to 140 rule of thumb should be used for most sand stones, silt stones, carbonates, and hard shales. In fact, trending more towards the 100 RPM mark has shown to be most effective. When an optimum RPM is determined, torque should be held constant by varying the WOB. In the case of drilling with motors, a motor pressure differential of around 250 to 350 PSI has been proven most effective. Maintain this differential by allowing the weight to vary between predetermined minimum and maximum values.


WOB – Roller Cone:

Due to the method in which roller cone bits fail rock (compression), WOB is closely related to the strength of rock being drilled. Harder formations will require higher weights in order to penetrate the tooth or tungsten carbide insert (TCI) into the rock. As previously mentioned, both RPM and WOB need to be optimized in order to achieve maximum cutter penetration and since each tooth or TCI can only penetrate a certain amount into the formation, excessive WOB will only lead to damage of the cone bodies. Historically, WOB for standard 7-7/8 or 8-3/4 roller cone applications would reach values as high as 60 KLbs. The nature of roller cone drill bits allows for excessive weights with low probability of damage to the cutting structure. However, many other parts of the bit (bearings, legs, posts, etc) can suffer damage at higher weight.



With PDC drilling, WOB is needed to achieve the torque required to sheer formation at a given depth of cut. The higher the depth of cut, the greater the torque required to efficiently sheer. The primary difference in how a PDC bit handles WOB when compared to a roller cone is that the cutting elements of a PDC bits are not designed to handle high weight loads. Both TCI’s and PDC cutters are designed to handle loading along the axis of the cutting element. In the case of roller cone bits, the axis of the TCI points along the axis of the drill pipe, and thus, is able to take higher WOB. In the case of PDC bits, the axes of the cutting elements point more perpendicular to the pipe axis and are designed to drill with torque. WOB directly adds loading to the side of the PDC cutter; in a direction the cutter is not designed to handle loading. Still, WOB is required (along with torque) to allow the PDC cutter to engage with the formation.


It can now be seen that PDC bits are more dependent on torque than WOB to drill efficiently. Too much torque will lead to torsional stick-slip environments. While it is important to maintain a good torque level, often times the WOB required to do so passes the magnitude where cutter failure begins. In these cases, it is important to note the maximum WOB allowable by a particular PDC design and not to remain in that range for extended periods of time. During these cases, the optimum torque levels may not be obtainable and patience is needed to make it through the harder sections. The WOB required to reach a certain optimum torque level varies by bit design and cutter size. Larger cutters require less weight in order to drill efficiently due to the large portion of cutter engaged with the formation. Likewise, smaller cutter designs require more WOB to reach the same engaged amount of diamond. Bits with greater numbers of cutters (more points of contact) can handle higher weight loads and vice versa. PDC manufacturers should always supply recommended WOB values for continued drilling, hard caps, and maximum allowable short-term needs.


Hydraulics – Roller Cone:

Roller cone hydraulics differs greatly from PDC hydraulics when the fluid aspects pertaining to hole-cleaning and cutter cooling are examined. Because of the compression-failure characteristics of roller cone drilling, there are small fragments of failed rock that do not readily clear away after the TCI has penetrated the formation. These fragments then have to be re-broken during the next bit revolution. This is why high HSI is desired with roller cone drilling. Maximum nozzle velocities will lift these residual fragments and increase drilling efficiency. The direction of nozzle is also important (as well as with PDC bits). When angled correctly, the fluid can both mitigate balling as well as optimize cutting evacuation time. The method of maximizing nozzle fluid velocity has been practiced for many years and is often misapplied with PDC drilling. It is important to understand that the hydraulic requirements of roller cone bits do not have the same parameters as PDC.


PDC Hydraulics:

There are two hydraulic parameters that hold the highest significance with PDC drilling. These are cutter cooling and cuttings evacuation. Because of the sheering nature of PDC drilling, any residual cuttings left on the hole-bottom (which is rare) will not drastically decrease the sheering efficiency of the bit. The main concern with the cuttings is keeping them off of the face of the PDC cutter as well as evacuating them away from the bit face. This can be accomplished with high HSI but is not necessary. In a sense, if the nozzle velocity is high enough, it will force the fluid and cuttings away from the bit face. However, with many formations (abrasive), this hydraulic method can cause severe bit erosion and lead to premature failure. A general rule of thumb is that abrasive slurry with a nozzle velocity of 90 ft/sec will begin to erode the matrix body material, decreasing cutter pocket integrity. Even more, the same scenario with a 120 ft/sec nozzle velocity will begin to erode the PDC cutter substrate (tungsten carbide). Erosion of this substrate will expose unsupported diamond and lead to cutting table failure. So, while high HSI can provide a working hydraulic scenario, it can also cause erosion damage and premature bit failure.


A more effective and desirable hydraulic scenario for PDC drilling is to increase TFA, decrease HSI, and hold nozzle velocity below the range of bit erosion. Cuttings evacuation time can be made efficient though optimized nozzle tilt angles and directions. Instead of forcing the fluid away from the bit face, the goal is to minimize fluid recirculation and eddy currents. This will allow the fluid to evacuate more directly from the bit face and decrease high velocity fluid around the cutters. When PDC drill bits were fairly new in drilling applications, high HSI (around 3) was thought to be most effective. Experience and multiple simulations (computational fluid dynamics) has shown that a more direct fluid path and HSI’s around 1 can remove cuttings from the bit face as efficiently as higher HSI’s. Also, increased cutter resistance to heat has lead to lower fluid velocity requirements for cutter cooling.


Formation type can play a key role in the hydraulic layout of PDC bits. Those applications involving abrasive formations should be drilled with higher TFA’s and lower fluid velocities. The worst case of this would be high-ROP sand stone applications where the formation readily becomes disassociated into solution (poor formation cementation). These types of formations cause the worst erosional environments when nozzle velocity is high (no matter how optimized the hydraulic layout can be). However, if balling is an issue in the application, higher fluid velocities near the cutters may be necessary. This can be achieved in low HSI applications by aiming the nozzles more toward the blade front. However, not all types of balling applications will require this. High fluid velocity near the cutters is necessary for “flash balling” scenarios. These scenarios involve sticky formations (like “gumbo”). “Secretion balling” requires a more efficient fluid path as opposed to higher fluid velocities at the cutter face. This type of balling tends to start higher in the junk slot and can be compared to the buildup of mud in a truck wheel well. The mud will begin to stick to the bit body in low pressure zones. Greater fluid evacuation efficiency will decrease the possibility of this happening.


All in all, PDC hydraulics should involve parameters closer to the lower end of well and rig requirements. Often times, flow rates are used that greatly exceed the needs of the well to efficiently remove cuttings. Hydraulic programs can be used to determine necessary flow requirements for hole-cleaning and conditioning. Exceeding these values and drilling with high HSI will generally do nothing to aid in PDC bit performance.



It is important to understand and visualize the differences in PDC and roller cone drilling. Optimum parameters for drilling with compression differ greatly from those for drilling through shearing. High RPM in many formations types can damage PDC cutters by inducing impact environments through poor crack propagation (inefficient shearing). Likewise, increased kinetic energy will lead to more rapid thermal degradation of PDC cutters in high RPM environments. High torque and consistent RPM provide an efficient sheering environment for a given formation type. RPM should depend on the formation type being drilled and trended more toward the lower side of the recommended value. WOB should only be high enough to obtain desired torque values as excessive weight creates loading in an undesirable direction. The PDC manufacturer should provide recommended WOB values as well as maximum allowable WOB for both sustained and short term needs. High HSI is not necessary for effective PDC hydraulics and regularly causes more damage than good. Smooth, efficient fluid evacuation from the bit face can be applied for most applications. Nozzle angle adjustments can be made to meet the needs of certain balling applications without increasing HSI. Good visual understanding of optimum RPM, WOB, and Hydraulic parameters for PDC drilling will definitely lead to increased footage and ROP.



Health, Safety & Environment (HSE)


Statement from the Managing Director


AOSG’s philosophy is that the Health and Safety of its people, and the protection of the environment, are the most important considerations in any of our business undertakings.  Health and Safety hazards are to be identified and any risks are to be managed to avoid detriment to the company's employees, subcontractors and the public. Environmental impacts resulting from our operations must be identified and removed, reduced or controlled.


The HSE Management System is designed to ensure the Company’s activities are controlled to protect personnel and the environment from identified risks by implementing necessary measures, maintaining documented procedures and work instructions, providing training, monitoring and measuring HSE performance, auditing and taking corrective action for non conformance.


The Management team are committed to ensuring all personnel are safety conscious and continue to improve their safety awareness. This will be achieved through leadership, communication, training, monitoring and measuring HSE performance.


We are committed to continuous improvement and to be successful in achieving our objectives we require that all our personnel are fully committed to the adherence of our policies and procedures.  Safety is the responsibility of all employees and everyone has the obligation to stop or suspend any work that they think is being carried out unsafely or that may damage the environment.


Eng. M Bozgia

Managing Director

Alamia Oil Services Group (AOSG)



Health and Safety Policy

AOSG has identified Health and Safety as four areas in its operations that are of vital importance and require effective control. These are:

·       Ensuring safety on all worksites

·       Prevention of  injuries and loss of life

·       Promoting the good health of its employees

·       Compliance with Client, Industry and local authority requirements

AOSG believes that accidents are preventable with the adoption of a comprehensive occupational health and safety system. AOSG are committed to implementing, maintaining and continuously improving an OH&S system which conforms to national laws and international standards applicable to our field of work.

AOSG will strive to develop and nurture a safety culture amongst its employees by providing training and promoting awareness. We will encourage employees to exceed OH&S performance by setting objectives which will motivate and providing feedback which will give our employees the push to aim higher.

AOSG has established a HSE Management System Manual which outlines the structure we will follow to implement this Health and Safety Policy.

It is AOSG’s desire to have a team who carry out their duties with safety at the forefront of their minds so we can proudly say we are a company with Safety in Practice.

Environmental Policy

AOSG’s is committed to ensuring that our operations are planned and carried out with sustainable development as a key factor in our consideration. AOSG will adopt international standards which will enable us to manage our activities while complying with international and local environmental legislation.

AOSG will assess the environmental impact of our operations, provide the resources to put the necessary control measures in place and seek to continuously improve our environmental performance.

AOSG will set company and department objectives which will motivate our employees to improve performance and provide feedback which will give them the push to continue striving for the company’s goals.

AOSG has established a HSE Management System Manual which outlines the structure we will follow to implement this Environmental Policy. AOSG is committed to meeting the needs of the present without compromising those of the future.